Author Topic: Ruined my NEW BRODAK 40 (Read 10902 times)

DanielGelinas · « **on:** April 22, 2013, 03:09:21 PM »

I was breaking in my B40 on an engine stand last Friday afternoon.
Breaking in as per instructions with 5% 23% oil.

Everything was going great for the first 16 runs. In fact, it was starting on the first or second flip.
Then I noticed it was difficult to start, had to prime it more... but it still started and I finished 20 two minute runs with ample cooling between runs.

When I brought it back home and looked into the exhaust, I saw a vertical groove in the piston...not good.

Then I looked with the magnifying glass and saw how deep it was.

When turning the prop, you can see thelittle bubbles coming out of the gap.

Probably a piece of metal in the engine. next time I will AWAYS DISASSEMBLE and INSPECT an engine before break in.

Live and learn...

-Dan

DanielGelinas · « **Reply #1 on:** April 22, 2013, 03:23:17 PM »

Hii Bill,

Unfortunatly, it was not purchased from John Brodak. I bought it used (NIB).

-Dan

Mike_Ostella · « **Reply #2 on:** April 22, 2013, 03:37:31 PM »

Hey Dan:

You may be able to get a new piston and sleeve if that's all that's ruined. The rod is what usually goes first.
Make sure that the screw holes in the head have enough play in them. Also make sure that the head fits comfortably in the cylinder sleeve. If it's too snug, it can distort the sleeve. In that scenario, the rod gets worn out in the break in process. I'm not saying that's what happened to your engine, but it's worth looking into.

Mike

bob whitney · « **Reply #3 on:** April 22, 2013, 03:49:51 PM »

Had the engine been run before you got it.?? i just bought a brodak 15 from Brodak , as i was looking it over i felt a scratchy feeling ,then it wanted to stop at the top of the exhost port ,so stripped it down and found a scratch the full length of the piston i called John and told him what happened and he sent me a new engine and asked for mine back so he could see what happened .. cant ask for anything more than that, i have noticed that not all the screws on the 25's and 15's are as tight as they should be ,so a good idea would be to pull the backplate and check for foreign matter and then retighten all the screws

Douglas Ames · « **Reply #4 on:** April 22, 2013, 04:11:43 PM »

"Swarf" from production. Bummer... $:-\$
A new P&L should fix it but then you just lost the "deal" you got.

DanielGelinas · « **Reply #5 on:** April 22, 2013, 04:18:53 PM »

Hi Guys,

This was a never run engine. I know its a first generation B40. I'm hoping the pistons and liners that Brodaks have will fit the older generation engine. I have sent him (J.B.) an email asking him about this.

Hopefully he can sell me a new one that will fit.

Or maybe I'll send him the engine...

-Dan

George · « **Reply #6 on:** April 22, 2013, 05:15:40 PM »

It's a good idea to flush out ANY engine that you get, new or used. While checking it, also look for flashing that might later break off...remove with a #11 blade. No manufacturing process is perfect and although you might get it repaired or replaced free, it's easier and quicker to check.

George

Lyle Spiegel · « **Reply #7 on:** April 22, 2013, 06:08:17 PM »

I'm a big fan of B40- those that know me know I have accumulated quite a few. have Never encountered any issue such as you have described. Last time I checked for B40 parts I recall that the P&L are sold individually. Its curious to me why they're not sold as a matched set since quality of the lapped fit has to be dead on and although I'm sure factory has good CNC machining capability its hard to imagine they have such tight control on tolerances that any piston can be setup with any liner. I would be interested to hear opinion / experience.of others.

Brett Buck · « **Reply #8 on:** April 22, 2013, 06:17:58 PM »

Quote from: George Bain on April 22, 2013, 05:15:40 PM

It's a good idea to flush out ANY engine that you get, new or used. While checking it, also look for flashing that might later break off...remove with a #11 blade. No manufacturing process is perfect and although you might get it repaired or replaced free, it's easier and quicker to check.

  It's SORT of a good idea on some engines. I would have not expected a problem in this case.

   I have seen a fair number, that is, more than a handful, of engines that appeared to be unnecessarily disassembled and then never ran properly. If we are talking a new PA or RO-Jett, I would discourage anyone from doing more than the very minimum work to get the venturi as you like it, but certainly not a "disassemble/clean/lube" like it was a McCoy 35 or even removing the backplate to flush them out. The chances of messing it up is higher than the chance of something actually being left in the engine.

I don't just mean people who have never done it. It's not rocket science (heh!) to get an engine apart and back together properly, but some of the cases I have seen were from people who should have should have known what they were doing and in one case is considered an expert of the highest order.

   I also have found no need to do this on most current consumer engines. I run the OS's straight out of the box and so far no damage. The likelihood of a problem is higher but still, it's a small enough probability that I would rather risk that than messing something up.

   The only engines I would recommend cleaning out are NOS or new Foxes, used engines (since you can't tell if they have been crashed and left dirty), or a "cottage industry" supplier other than Randy or Dub. Most of the latter mean well but unless you are sure, I would take off the backplate and flush them out. I have seen too many of the reworks eat themselves up from left-over machining debris that it outweighs my reluctance to avoid a possible assembly error.

   Brett

DanielGelinas · « **Reply #9 on:** April 22, 2013, 07:23:45 PM »

Just checked with Brodaks. As you said Lyle, they are not matched. I'm not sure they have to be though, since they are usually very tight at the top when new. I'm assuming the standard brodak recommended break-in would work on any piston liner match...

Too bad they are out of stock again.

anyhow, I'll put the engine on a plane and see if I really am too low on power because of this scratch.
Heck, maybe it will get better as it runs.

-Dan

Mike_Ostella · « **Reply #10 on:** April 22, 2013, 08:14:05 PM »

We discovered several that were tight at the top when they were new. When we took off the head the holes in the head didn't allow enough play for easy alignment. We drilled them out a bit. Fixed that issue. Also, the sleeve came out with the head because the part of the head that is supposed to slip comfortably inside the sleeve was too tight. Without the head on, the piston sleeve fit was fine, but once we put the head back on, the engine seemed too tight at the top. We guessed that the head was distorting the sleeve, so we took a few thousandths off that part of the head that goes into the sleeve. Result was quick easy break ins that didn't destroy the rod. All this discovered and analyzed by Doug Benedetti. I'm not saying that they all suffer from this, but if you have a new one, check it out before you run the engine

Douglas Ames · « **Reply #11 on:** April 22, 2013, 08:40:41 PM »

Quote from: Mike_Ostella on April 22, 2013, 08:14:05 PM

We discovered several that were tight at the top when they were new. When we took off the head the holes in the head didn't allow enough play for easy alignment. We drilled them out a bit. Fixed that issue. Also, the sleeve came out with the head because the part of the head that is supposed to slip comfortably inside the sleeve was too tight. Without the head on, the piston sleeve fit was fine, but once we put the head back on, the engine seemed too tight at the top. We guessed that the head was distorting the sleeve, so we took a few thousandths off that part of the head that goes into the sleeve. Result was quick easy break ins that didn't destroy the rod. All this discovered and analyzed by Doug Benedetti. I'm not saying that they all suffer from this, but if you have a new one, check it out before you run the engine

Some engines are designed that way to account for thermal expansion, which is greater at the top then bottom of the liner. The theory is when the engine is at operating temp., the cylinder is straight and the piston has a good seal throughout it's travel.

Dick Pacini · « **Reply #12 on:** April 22, 2013, 08:42:32 PM »

According to the instructions that came with my Brodaks, the pinch at the top is the way they were designed and proper break-in will result in a proper fit.

Mike_Ostella · « **Reply #13 on:** April 22, 2013, 09:08:19 PM »

Our mods don't take away the pinch, they just remove all possibility of an egged sleeve.
Just trying to help
mods must be done before the motor is run.
Mike

Andrew Tinsley · « **Reply #14 on:** April 23, 2013, 08:08:20 AM »

Hello Brett,
I have always been surprised at your strict mantra "to leave engines well alone". I have a long history of dismantling and repairing engines and never had a problem. In fact a lot of the old sparkers that I run, demand some serious attention, to return their performance to "as new". So I thought that you were overdoing the warnings.
A year or so ago, I made a suggestion for an engine repair, on another forum and eventually found that the huge majority of folk there, wouldn't have a clue how to disassemble an engine, let alone put it back together.
I was pulled up sharp when I said that I used a 12 volt supply with a current limiter to fire up my glowplugs, Someone simply ignored the "with a current limiter" and hooked up 12volts to his plug and was not pleased when it blew! So from now on I shall be ultra careful of what I say in public! It won't stop me from repairing my old engines though!

Regards,

Andrew.

RC Storick · « **Reply #15 on:** April 23, 2013, 08:21:09 AM »

Quote from: Andrew Tinsley on April 23, 2013, 08:08:20 AM

A year or so ago, I made a suggestion for an engine repair, on another forum and eventually found that the huge majority of folk there, wouldn't have a clue how to disassemble an engine, let alone put it back together.

Regards,

Andrew.

Amen to this statement. Awhile back I posted about putting something in the microwave to renew its properties. I later got a letter of displeasure from the person getting burned. I also sometimes do things with dope that can burn your house down. This is why I have never publicly given the instructions. I stay away from any tips or tricks that I use that are potentially dangerous (and there are many) that I use to save time. Not everything you see here is correct and not everyone here knows what they are talking about. The internet is full of so called experts who have no clue.

Brett Buck · « **Reply #16 on:** April 23, 2013, 08:59:58 AM »

Quote from: Andrew Tinsley on April 23, 2013, 08:08:20 AM

I have always been surprised at your strict mantra "to leave engines well alone". I have a long history of dismantling and repairing engines and never had a problem. In fact a lot of the old sparkers that I run, demand some serious attention, to return their performance to "as new". So I thought that you were overdoing the warnings.

   I have seen too many people ruin engines by casual disassembly to suggest anything else. I specifically mean new-from-factory modern engines. And it's not just people misunderstanding instructions or not being competent modelers. Two of the more notable incidents were by a World Champion and a National Champion, both of whom had undoubtedly taken engines apart successfully many times before. The question is *why* do you think you need to take a brand new $400 engine straight from the manufacturer, go to the kitchen counter, and take it all apart? It may or may not have solved the problem mentioned in this thread, but what are the odds of that VS the odds of random fiddling messing something up?

   The old "disassemble-clean-lube" was probably safer when engines were not built to the current tolerances and had to be run for hours just to get the fit right. Even then, I suspect that casual disassembly caused a bunch of problems, just not enough to tell the difference with the more-or-less random performance you got even in the best of conditions. It may have been more necessary then, because the cleaning might not have been great when you are selling an complete .35 cu in engine for $3.95, cheap even by standards of the day.

   No reputable manufacturer routinely leaves grit or burrs in engines these days, if they do, they will have no reputation in short order. So what is accomplished? You might occasionally save an outlier but even then that is by no means assured.

   If there is something wrong with the engine, that's a different story, and you should do what it takes to fix it. But there's no reason to assume that there is a problem without any indications.

   Brett

john e. holliday · « **Reply #17 on:** April 23, 2013, 09:19:35 AM »

I think that is why Fox, K&B, McCoy and Johnson all said to run the engines the first time is to get any crud left in the engine out of the exhaust ports. I had a few I removed the back plate on and could find nothing. Todays engines are meant to be run out of the box by people that don't know better. My first Brodak .40 I too followed the instructions of 20 2+minutes of run time only to find it was not even close to being broke in. I think it is still breaking in. Also how many people remember to lubricate any engine before turning it thru. The Brodaks instruction state this, "Do not turn engine over until some oil or fuel is put in".

Brett Buck · « **Reply #18 on:** April 23, 2013, 12:08:54 PM »

Quote from: john e. holliday on April 23, 2013, 09:19:35 AM

Todays engines are meant to be run out of the box by people that don't know better. My first Brodak .40 I too followed the instructions of 20 2+minutes of run time only to find it was not even close to being broke in. I think it is still breaking in.

"people who don't know better"? Why is it some laudable virtue that engines aren't ready to go out of the box? The requirement for break-in is a defect - probably unavoidable at any reasonable cost, but certainly not a good thing. The engines should be safe to run right off the bat without any prior or advanced knowledge. For the most part, they ARE safe to run, including the Brodak engine you refer to.

That doesn't mean that it won't get better but at least you won't destroy them by improper break-in like the aforementioned Fox/Johnson/McCoy. In the latter two cases, you had to run them for a very long time just to get enough carbon to fill up the pores in the sintered metal piston.

Brett

Brad Smith · « **Reply #19 on:** April 23, 2013, 12:31:55 PM »

I have taken Brodak 40s right out of the box and put them on planes and run them after about 6 or 7 runs they seem to settle down some i dont think you hurt your motor i would use it as is see what happens.they dont like alot of castrol at least mine dont.

Paul Smith · « **Reply #20 on:** April 23, 2013, 03:53:40 PM »

I would not feel honest about going back to the manufacturer with a problem with something I bought used.
The person who sold your this engine would be the responsible party.
Mr. Brodak is a nice person. He would really be generous if he gave relief to an aftermarket buyer.
I don't know how much you paid, but $100 was list price last when I bought one.
If you'd bought direct he would have replaced it based on your e mail or fone call and trusted you to return the bad unit.

Paul Allen · « **Reply #21 on:** April 23, 2013, 03:57:37 PM »

Daniel
The later piston and liner will fit the first model.
I replaced these in my first B40 when it dropped a circlip,
from the wrist pin, now that was a groove !
The only drama was it took 2 years to get the replacement parts.
Paul
In OZ

jim ivey · « **Reply #22 on:** April 23, 2013, 04:58:08 PM »

sorry to hear that. I have a BNB btodak40 It's way to tight to consider running. pnc feels like metal 2 metal , not good.. I was goimg to borrow my friends' sunnen hone anf free ip the shaft and pnc. its never been started. call me if you want it. 661-802=4818. jim ps

Dick Pacini · « **Reply #23 on:** April 23, 2013, 05:14:54 PM »

Quote from: jim ivey on April 23, 2013, 04:58:08 PM

sorry to hear that. I have a BNB btodak40 It's way to tight to consider running. pnc feels like metal 2 metal , not good.. I was goimg to borrow my friends' sunnen hone anf free ip the shaft and pnc. its never been started. call me if you want it. 661-802=4818. jim ps

Mount it on a suitable bench, prime with a couple drops of the recommended fuel and flip the prop. The instructions are specific about the pinch at the top and not to try rolling it over slowly. After the recommended break-in, you will find that the pinch is almost completely gone.

DanielGelinas · « **Reply #24 on:** April 23, 2013, 08:04:02 PM »

To Paul Smith:
I would not think that John Brodak would change the engine for a new one. There is no reason for him to do so and in fact, I would never ask him to do so.
The reason I didn't buy from him in the first place is that there were none available when I wanted one (for more than a year). Check their website as we discuse this. There are none available again now...
So, I bought a new one from a member of the forum. I can't blame the seller either as it was a NEW in BOX engine. The seller couldn't know it could have had a defect since he never tried running it.

To Jim Ivey:
Jim that is very generous on your part, thank you. But as Dick P. has mentioned, I think this is perfectly normal for this engine. You should put a couple of drops of oil and fuel in it and try starting it. You will be surprised at how fast they break in. I know you are a fox and McCoy lover, (so am I), but this is really a great engine.

john e. holliday · « **Reply #25 on:** April 24, 2013, 05:49:51 AM »

Reread the instruction that came with my Brodak .40's. DO NOT FLIP PROP OR PULL THRU WITHOUT FUEL OR OIL IN THE EXHAUST. I even put some in the intake before flipping. Have a good heavy glove for first starts. It gets easier each time you start it.

Jim Thomerson · « **Reply #26 on:** April 24, 2013, 07:05:50 AM »

George Aldrich said that the main thing he did for engines was to fit them together properly, and the first thing that a modeler would do when getting his engine back was to take it apart to see what had been done to it.

Assuming the part of the head that goes down into the cylinder is round, it is good to have a tight fit in the cylinder. This is true at least on iron and steel. This is one of the things George advocated. I found a good fitting head to be worth a thousand RPM over a similar sloppy head on racing engines.

bob whitney · « **Reply #27 on:** April 24, 2013, 08:29:20 AM »

there is a fine line between snug and too tight on the fit of the head . a steel liner will not expand as much as the aluminum head ,so as it gets hot the fit will tighten up . with an
aluminum or brass sleeve the ex-pansion
is about the same . the head will have less silicone so will still expand slightly more than the sleeve .if it is too tight it will expand and expand the top of sleeve , which cause's all kinds of problems like hard starting when hot.

Brett Buck · « **Reply #28 on:** April 24, 2013, 08:35:29 AM »

Quote from: jim ivey on April 23, 2013, 04:58:08 PM

sorry to hear that. I have a BNB btodak40 It's way to tight to consider running. pnc feels like metal 2 metal , not good.. I was goimg to borrow my friends' sunnen hone anf free ip the shaft and pnc. its never been started. call me if you want it. 661-802=4818. jim ps

I know you probably won't listen, but DON'T "loosen it up". If it makes a squeaking sound at TDC and tends to get stuck, that's CORRECT.

Brett

DanielGelinas · « **Reply #29 on:** April 24, 2013, 02:18:53 PM »

Question for thos that have well used B40's:
I have another B40 (used) that I can see the brass at the top of the piston when I look through the exhaust.
Is this normal or is this the sign of a well used B40? I have no idea how much time the engine has.
-Dan

RC Storick · « **Reply #30 on:** April 24, 2013, 02:20:47 PM »

Quote from: Brett Buck on April 24, 2013, 08:35:29 AM

I know you probably won't listen, but DON'T "loosen it up". If it makes a squeaking sound at TDC and tends to get stuck, that's CORRECT.

Brett

Brett is correct. Break in this engine do not hone it! The squeeze at the top is normal! Even if it squeeks.

RandySmith · « **Reply #31 on:** April 24, 2013, 03:58:08 PM »

Quote from: jim ivey on April 23, 2013, 04:58:08 PM

sorry to hear that. I have a BNB btodak40 It's way to tight to consider running. pnc feels like metal 2 metal , not good.. I was goimg to borrow my friends' sunnen hone anf free ip the shaft and pnc. its never been started. call me if you want it. 661-802=4818. jim ps

Hi Jim

The Modern engines that use a brass or aluminum sleeve "have" to be fitted tight with either a pinch or a tight fit at the top. The reason for this is the brass and Al. has a much higher expansion co-efficient than steel does, so by design they have to be fitted tight at the top... the sleeve will expand away from the piston, if it is not tight it will not run well and will have little power. Please do not hone the AAC p/s of the Brodak... or send it to me !

Also do not turn the motor over without putting oil in the piston/sleeve, and never turn it over TDC slowly, alway flip it briskly with oil or fuel in it ,if you have to flip it please heed this caution. These are NOT anything like a steel and iron P/S set.

Regards
Randy

bob whitney · « **Reply #32 on:** April 24, 2013, 08:11:33 PM »

the B40 has an aluminum sleeve so you should be seeing any brass , it could just be a caster coating on the sleeve

GonzoBonzo · « **Reply #33 on:** April 24, 2013, 09:13:30 PM »

If the pinch is that tight, try heating the case with a heat gun right before you start it for the first time. Makes life easier. Mandatory practice with high strung ABN .21 racing engines used in buggy's that start off of the flywheel with a bump box.

Gonzo

pipemakermike · « **Reply #34 on:** April 25, 2013, 03:14:15 AM »

Back in 2005 I did a lot of flying with a B40 and I think that I learnt a lot. The engine from new was vicious to handle when starting and I got a lot of clouts from the prop during the running in. I reported the problems here:-
http://www.clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=283575&mesg_id=283575&listing_type=search
and
http://www.clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=166392&mesg_id=166392&listing_type=search

One thought that I had was that the score in the side of the piston could have been caused by some casting inclusion that has come free during the running. My first B40 has a very porous patch in the casting. (see picture) This is a picture from the front of the engine when I was investigating the very slack fit of the shaft after only a years competition. I bored out the case and fitted a new bronze bush.

Paul Allen · « **Reply #35 on:** April 25, 2013, 06:37:14 AM »

Daniel
Does it look like this?

DanielGelinas · « **Reply #36 on:** April 25, 2013, 06:56:44 AM »

Paul, that is EXACTLY what it looks like.

Now, is that a good thing or a bad thing?

Mike, thanks for your input. I did read your older posts. I hope I don't run into as much trouble as your did in the past!!

Thanks to all for your replies!

-Daniel

Paul Allen · « **Reply #37 on:** April 25, 2013, 07:18:57 AM »

Daniel should be OK , this photo is from my other B40 and it runs fine.

Jim Thomerson · « **Reply #38 on:** April 25, 2013, 10:09:29 AM »

I have several Tower 40s, which are a favorite engine. A couple of them were so tight, I could not flip them. If I took the glow plug out, then I could flip them. I had an extra head and took the dremel to it to make a low compression head. This cured the can't flip problem. One run on the low compression head and the engine was fine with a regular head. I never understood what was going on.

Once I had been running diesels and had diesel fuel in the tank on the test stand. I ran one of the Towers with my low compression head on the diesel fuel. It ran, but was the most under compressed I have heard a diesel run. Seem like it fired every three or four revolutions.

Balsa Butcher · « **Reply #39 on:** April 25, 2013, 12:04:57 PM »

I don't even try to flip them in the direction of rotation if they are tight. Brodaks I break (hate that term) in by starting with the slap, bump whatever you want to call it method. Direct prime the engine then "flip", "slap", or whatever the prop in the opposite direction of rotation so it bounces back against the compression and starts. It will not make the engine start in reverse. It will propel the prop over the pinch. After a couple of start this way you will be able to flip it normally - not that you would want to. Works for all engines. Takes a little practice. Mandatory for Brodaks and other engine with tight top ends. No honing or heating necessary. This method was discussed in detail either here or on the other forum but I am unable to come up with the source right now.

Phil Bare · « **Reply #40 on:** April 26, 2013, 12:08:59 PM »

Dan, It always pays to at least remove the head and back plate of all new or new to you engines and inspect carefully for machining shaveings. I have been doing it since the early 1950s and have saved a few that would have been damaged other wise.
It would be sad to trash a new $400.00 Ro Jett or PA by not taking 20 minutes to make sure that all was clear.
Phil

Brett Buck · « **Reply #41 on:** April 26, 2013, 01:11:42 PM »

Quote from: Phil Bare on April 26, 2013, 12:08:59 PM

Dan, It always pays to at least remove the head and back plate of all new or new to you engines and inspect carefully for machining shaveings. I have been doing it since the early 1950s and have saved a few that would have been damaged other wise.
It would be sad to trash a new $400.00 Ro Jett or PA by not taking 20 minutes to make sure that all was clear.
Phil

It would be sad to trash a new $400 PA or RO-Jett by someone disassembling an engine that didn't need any cleaning, too. And that has certainly happened.

You just paid an expert $400 to put it together properly - do you think Randy forgot to clean the shavings out of it?

The only new engines that I would disassemble and check as a matter of safety are Foxes and anything from the Eastern Block (which I guess includes Brodak). Otherwise, either you can be reasonably certain they are clean.

Used is another story, of course.

Brett

Randy Ryan · « **Reply #42 on:** April 26, 2013, 01:28:44 PM »

Quote from: Brett Buck on April 26, 2013, 01:11:42 PM

It would be sad to trash a new $400 PA or RO-Jett by someone disassembling an engine that didn't need any cleaning, too. And that has certainly happened.

You just paid an expert $400 to put it together properly - do you think Randy forgot to clean the shavings out of it?

The only new engines that I would disassemble and check as a matter of safety are Foxes and anything from the Eastern Block (which I guess includes Brodak). Otherwise, either you can be reasonably certain they are clean.

Used is another story, of course.

Don't forget Chinese, they are notoriously filthy though I guess we don't us allot of Chinese engines in stunt. I've bought a few diesels new that were unbelievably full of swarf, absolutley no post machining cleaning was done.

Brett

Brett Buck · « **Reply #43 on:** April 26, 2013, 02:41:16 PM »

Quote from: Randy Ryan on April 26, 2013, 01:28:44 PM

Don't forget Chinese, they are notoriously filthy though I guess we don't us allot of Chinese engines in stunt. I've bought a few diesels new that were unbelievably full of swarf, absolutley no post machining cleaning was done.

Right, I left them out because they aren't commonly used as stunt engines. I haven't seen any with a new-manufacture ST (also made in China) in years.

Brett

Phil Bare · « **Reply #44 on:** April 26, 2013, 03:01:18 PM »

Brett, I think that anyone can inadvertantly miss shavings or swarf when assembling new engines no matter who they are. As I said, it would be sad to trash a new $400.00 engine when it would take twenty minutes to pull the head and back plate off and check.
It s my opinion that a modeler who has advanced to the point of using $400.00 dollar engines has more than enough mechanical savvy to tear down any engine, inspect it and reassemble it properly.

Phil

Joseph Lijoi · « **Reply #45 on:** April 26, 2013, 03:14:40 PM »

Quote from: Phil Bare on April 26, 2013, 03:01:18 PM

Brett, I think that anyone can inadvertantly miss shavings or swarf when assembling new engines no matter who they are. As I said, it would be sad to trash a new $400.00 engine when it would take twenty minutes to pull the head and back plate off and check.
It s my opinion that a modeler who has advanced to the point of using $400.00 dollar engines has more than enough mechanical savvy to tear down any engine, inspect it and reassemble it properly.

Phil

All due respect, I seriously doubt that any reputable engine builder in any motor sport would last very long in charging you big bucks for an engine that is not cleaned and fitted, let alone modified.

Phil Bare · « **Reply #46 on:** April 26, 2013, 03:59:58 PM »

As I sai, anyone can inadvertantly miss some thing. I prefer to check them.

Brett Buck · « **Reply #47 on:** April 26, 2013, 06:01:14 PM »

Quote from: Phil Bare on April 26, 2013, 03:01:18 PM

Brett, I think that anyone can inadvertantly miss shavings or swarf when assembling new engines no matter who they are. As I said, it would be sad to trash a new $400.00 engine when it would take twenty minutes to pull the head and back plate off and check.
It s my opinion that a modeler who has advanced to the point of using $400.00 dollar engines has more than enough mechanical savvy to tear down any engine, inspect it and reassemble it properly.

  Probably - but why risk it? I am sure that Randy could (if he was willing to discuss the topic - and I certainly wouldn't blame him if he didn't!) regale us with stories about guys to took the engine apart, then complained it didn't work.

   Tearing down engines on a regular basis went out with $3.95 McCoy 35 Redheads on bubble packs, as far as I can tell. And I do know for certain that more engines are screwed up by casual disassembly and misassembly than are damaged by crud that people like Randy and Dub Jett missed.

   Having said that, there are a few "engine experts" out there that I would be tempted to inspect before use, but an even better way to avoid the issue is to avoid these particular "experts".

It's unfortunate that his particular engine appears to have gotten scored by stray debris but that seems to be the exception rather than the rule. And there's no amount of back-plate removing that would fix the porous casting (and the likely sand embedded in it) shown above!

   Brett

Phil Bare · « **Reply #48 on:** April 27, 2013, 07:42:06 AM »

Brett, The Brodak engine that is the topic of discussion is the perfect example of why a disassembly and inspection can be worth while.
It is hard for me to imagine that there are many modelers who have the experience and money to be using a $400.00 engine who would be incapable of taking it apart and reassembling it, after all, we are not talking about a four cam V12 Ferrari.

Phil

john e. holliday · « **Reply #49 on:** April 27, 2013, 08:07:03 AM »

Used to be in the early years you voided the warrenty that came with an engine. I've had Fox's replaced with no questions asked when one destructed it self.

RandySmith · « **Reply #50 on:** April 27, 2013, 11:00:02 AM »

Quote from: Phil Bare on April 27, 2013, 07:42:06 AM

Brett, The Brodak engine that is the topic of discussion is the perfect example of why a disassembly and inspection can be worth while.
It is hard for me to imagine that there are many modelers who have the experience and money to be using a $400.00 engine who would be incapable of taking it apart and reassembling it, after all, we are not talking about a four cam V12 Ferrari.

Phil

\
I will add this, there are many modelers that can and have no problems taking apart an engine and reassembly, then there are many who cannot do that with all engines, There has been many engines ruined or damaged from trying to take apart then reassemble, there has also been many sleeves and cases ruined by people welding them together (dry assembly etc..) many cases ruined from bearings improperly installed, many ball bearings killed from improper installation, same thing with C clips , rods, etc.
None of this includes stripped out cases , and stuff like that
Some engines also take special tools or equipment to install properly, like dedicated bearing pushers, and some need special knowledge on how to do certain jobs related to install

Randy

Phil Bare · « **Reply #51 on:** April 27, 2013, 01:07:42 PM »

Randy, No doubt that you have seen it all, no question about that. Each person should know their own abilities and proceed accordingly.
Over the years, I have saved a few by disassembling and inspecting before running them.

Phil

Garf · « **Reply #52 on:** April 28, 2013, 07:09:52 PM »

I do know that there are people out there that need to be kept away from tools. Thankfully not many build planes.

john e. holliday · « **Reply #53 on:** April 30, 2013, 05:32:06 AM »

Speaking of dirt in fuel bulb, did have a peice of sand/dirt get into the exhaust port of my first TeeDee .15. Had a groove on one side of the piston. But, the engine ran and started better after that.

Brett Buck · « **Reply #54 on:** April 30, 2013, 02:43:57 PM »

Quote from: Phil Bare on April 27, 2013, 07:42:06 AM

Brett, The Brodak engine that is the topic of discussion is the perfect example of why a disassembly and inspection can be worth while.
It is hard for me to imagine that there are many modelers who have the experience and money to be using a $400.00 engine who would be incapable of taking it apart and reassembling it, after all, we are not talking about a four cam V12 Ferrari.=

Granted, it MAY have been corrected by this, but it's a matter of odds of occasionally catching debris VS frequently screwing it up with improper assembly. Most people have absolutely no idea what they are doing, whether they think so or not. Just like most "engine experts" - many of the people reworking engines today, or providing advice, have absolutely no idea what they are talking about, and moreover, have no idea that they don't know what they are talking about. They offer advice and modification with perfect sincerity and are absolutely convinced they are right, but they aren't.

I have seen it over and over, people take apart engines unnecessarily, get it back together wrong, then it never works, then complain the engine is no good. Or fail to follow the directions, throw away half the parts because they "aren't stunt parts" and never have it work and complain the engine is no good. Or have it work perfectly, but not like their preconceived notion of how a "stunt motor" is supposed to work, complain it is "no good", then proceed to "fix it". And then frequently offer the "fixing" advice and service to others. With absolute conviction, but absolutely wrong.

Brett

Phil Bare · « **Reply #55 on:** April 30, 2013, 04:26:26 PM »

Brett, Tear it down and inspect and reassemble or run it with swarf in it.
I guess that hearing it run untill it destroys the P & L is rewarding to some and buying a new P & L and tearing it down anyway does have some merit.

Phil

Brett Buck · « **Reply #56 on:** April 30, 2013, 05:03:26 PM »

Quote from: Phil Bare on April 30, 2013, 04:26:26 PM

Brett, Tear it down and inspect and reassemble or run it with swarf in it.
I guess that hearing it run untill it destroys the P & L is rewarding to some and buying a new P & L and tearing it down anyway does have some merit.

Phil

If you actually knew there was crud in it beforehand (like a Fox) you would be right. Given that this is a *very rare occurrence* with modern engines, it's a different set of odds. I see far more engines damaged by fiddling then I do from stray debris.

Brett

Phil Bare · « **Reply #57 on:** May 01, 2013, 06:11:44 AM »

Brett, If you knew that there was 'crud' in it to start with, wouldn't you tear it down and clean it?
Anyway, my experience has been that no matter the name on the engine, it pays to dissassemble and inspect before running. Thats my opinion, yours may differ.
Oh, the Brodak .40 that is the subject of the thread is the perfect example.

Phil

Brett Buck · « **Reply #58 on:** May 01, 2013, 08:23:40 AM »

Quote from: Phil Bare on May 01, 2013, 06:11:44 AM

Brett, If you knew that there was 'crud' in it to start with, wouldn't you tear it down and clean it?

YES, since that's what I said earlier! That's not the question, the question is whether or not the chance of having crud inside is greater than the chance of damaging it by idly taking it apart. The answer appears to be, in most cases, that you are better off leaving it alone.

Brett

Phil Bare · « **Reply #59 on:** May 01, 2013, 10:39:11 AM »

Brett, my opinion differs from yours. I think that the mechanical aptitude of the vast majority of modelers is way above average and that the biggest majority are more than capable of tearing down, inspecting, cleaning, and reassembling the model engines that we use.
Few of us would 'idly' tear down a used engine, much less, a new one.
If you are not comfortable tearing down your LA 46, don't do it.

Phil

RandySmith · « **Reply #60 on:** May 01, 2013, 12:24:44 PM »

To add a little clarity to this, there is a huge difference tearing down a LA, FP FOX or Brodak, than say a PA , JETT, Saito , and ones with pressed in bearings and other more complicated, some are very hard, even for master mechanics to take apart and reassemble , other are almost impossible without special tools. And YES I have seen several engines killed very badly by some that were engine mechanics by trade, mainly because the were unfamiler with the way they were put together, and some did not have the special tools needed..ie.. seat bearings and press them , removed pressed in sleeves, remove pressed in pins etc

Bottom line many engines are simple, some are NOT, and the Brodak shown with the casting flaws would not be fixed by 95% of modelers, that one needed a new case or a machinist to install a new front bushing. I have seen many more engines with what I call voids or blow holes that can be cleaned, and then have specs/chips/dots of metal come out of them and ruin an engine.

Randy

FLOYD CARTER · « **Reply #61 on:** May 01, 2013, 03:12:15 PM »

I am still amused at the suggestion (I saw it here!) of pounding a worn piston to expand it to fit better (?).

Maybe it works. I don't know. I would not try it.

F.C.

Steve Thomas · « **Reply #62 on:** May 02, 2013, 06:48:35 PM »

FWIW a good friend of mine distributes and repairs engines, as well as making his own, and people who insist on pulling them apart are the bane of his life. Obviously it isn't an issue if you've got the requisite skills, but there are plenty of people out there who don't, it seems.

While there are some engines that are known offenders when it comes to swarf, there isn't much to be gained in stripping down an engine that's been meticulously cleaned half a dozen times during assembly and then test-run.

Jim Kraft · « **Reply #63 on:** May 02, 2013, 09:22:43 PM »

Clarence Lee recommended taking the back plate off to check for stuff that could cause problems as the bottom end is where most of it would be. Of course that was many years ago when engines were not as clean from manufacture as they are now. I work on a lot of old ignition engines and find many times they have been assembled wrong. I have found late model Ohlsson's with the rod bushing backwards, Anderson Spitfires with the spacer that goes between the back of the piston and the rod on the front side. I almost always remove the back plate on all of the engines that I come across just to check before running. It has saved some from damage. I have also replaced crank cases on Saito's that the R/C guys brought to me after they tried to "fix" them.

Allen Eshleman · « **Reply #64 on:** May 04, 2013, 05:30:50 AM »

I would like to know if Daniel has been able to fix the engine, getting it to run good, again.

Andrew Tinsley · « **Reply #65 on:** May 04, 2013, 09:24:47 AM »

Hello Floyd,
I too was amused at the suggestion that you could knock a piston about to make it fit better. I was shown how this could be done with the notorious Red head McCoy 35. Much to my amazement it worked! A tap or two on the dome of the piston crown, expanded the piston to make a good seal, a little running in and the engine was a good one!
With something as disposable as a McCoy 35, you have nothing to loose if the piston seal is worn out! When I was even more broke than I am now, I restored a McCoy 35 this way and it ran well for a couple of seasons before it wore out. Another session with the piston (disassembled!) and the compression was restored and a little running in ........ The engine is now retired as worn out again, but no doubt a session with the toffee hammer ............
The moral of the tale is that not all screwball solutions are as screwball as they sound!
A word of warning, this sort of thing will work with a sintered piston (McCoy and Johnson are some examples) hit a cast iron piston and you are on your own!

Andrew.

Mike Greb · « **Reply #66 on:** May 04, 2013, 10:37:35 AM »

Over the years I have heard stories of people using pipe cutters to raise up some metal to restore compression. I got a junk Fox Combat special Mk3 at a flea market. Tried the pipe cutter trick on the piston. Could not hardly make a mark, and then the top of the piston popped off. Oops......

DanielGelinas · « **Reply #67 on:** May 05, 2013, 07:09:21 PM »

Quote from: Allen Eshleman on May 04, 2013, 05:30:50 AM

I would like to know if Daniel has been able to fix the engine, getting it to run good, again.

Hi Allen,

I'm still waiting on John Brodak to get back to me. He mentioned that the latest piston and liner will fit on the 1st generation B40. I'm probably going to have J.B. change it for me...

I am flying my oriental with a OS 35S while I wait.
Last Friday I was flying my old super clown with fox35. In mid flight, the outside wing fell off and the engine went dead lean. Managed to land the thing at the end of the tank without further damage.

I guess I couldn't do that with an RC plane.

-Dan

Jim Thomerson · « **Reply #68 on:** May 06, 2013, 02:16:09 PM »

I wonder, suppose you went to an all castor fuel and put couple of hot runs on your Brodak 40, would it be possible for the scratches to get filled with castor varnish and solve your problem?

Tim Wescott · « **Reply #69 on:** May 06, 2013, 02:20:20 PM »

Quote from: FLOYD CARTER on May 01, 2013, 03:12:15 PM

I am still amused at the suggestion (I saw it here!) of pounding a worn piston to expand it to fit better (?).

Oh, pounding on a piston, that's definitely out.

Inertially upsetting it, however, sounds cool enough that it would just have to work.

DanielGelinas · « **Reply #70 on:** May 06, 2013, 07:40:28 PM »

Quote from: Jim Thomerson on May 06, 2013, 02:16:09 PM

I wonder, suppose you went to an all castor fuel and put couple of hot runs on your Brodak 40, would it be possible for the scratches to get filled with castor varnish and solve your problem?

Hi Jim,

I'm assuming the castor would be washed off as soon as i use 50/50 (10-23) fuel... but it may be Worth a try. On the other hand, a new piston and liner is not that expensive.

-Dan

Mark Scarborough · « **Reply #71 on:** May 06, 2013, 09:18:44 PM »

Quote from: Tim Wescott on May 06, 2013, 02:20:20 PM

Oh, pounding on a piston, that's definitely out.

Inertially upsetting it, however, sounds cool enough that it would just have to work.

Tim heres an idea,, just put a bb in the combustion chamber then run it,, or even spin it over with the electric finger,, saves all that pounding LOL

actually I have a McCoy that this was done to,, converted it from a non runable to a good runner,, I do not recomend it, well lets say I wont do it personally,, but I know who I will if I need it done again

Dick Pacini · « **Reply #72 on:** June 02, 2013, 10:02:48 PM »

I remember way back when that taking a piston and liner apart of a used engine was not recommended because it would be virtually impossible to seat the liner in the exact position it was. As a result, the microscopic grooves between the piston and liner would never line up and the engine would wear out much sooner.

L0U CRANE · « **Reply #73 on:** June 10, 2013, 01:55:14 AM »

Heckuva agument here...

Personal view: If I have Randy or Tom Lay or any other REPUTABLE engine builder do me an engine, I will leave it as received. I'll trust they cleaned it well and assembled it optimally.

Otherwise, I'll be tempted - at least - to do a FOD Walk.

I have found many engines poorly assembled as NIB. Even with the gains in CNC and precision dimensions, and with sturdier basic designs, I've seldom found a mass market engine that did not gain from properly remounting the head.

If the fit is not as free with the head torqued-in as it was with all loose, barring the TDC Squeak zone, of course, something is out of alignment. Most NIB engines I've looked into were not optimally torqued. Maybe over 50 years of playing this piano have endowed a delicacy to my touch?

Maybe I shouldn't encourage less experienced modellers to do what I do? Whatever... I'm more comfortable having done such a check, and others that can catch burrs, wear, bad fits, etc. before first run.

We get, pretty much, what we pay for. A mass-produced item is subject to risk from tolerance drift and variations in assembly. A highly developed and executed custom engine should not be, or we're wasting the money going there.

Bill Little · « **Reply #74 on:** July 19, 2013, 01:08:06 PM »

Quote from: L0U CRANE on June 10, 2013, 01:55:14 AM

Heckuva agument here...

Personal view: If I have Randy or Tom Lay or any other REPUTABLE engine builder do me an engine, I will leave it as received. I'll trust they cleaned it well and assembled it optimally.

Otherwise, I'll be tempted - at least - to do a FOD Walk.

I have found many engines poorly assembled as NIB. Even with the gains in CNC and precision dimensions, and with sturdier basic designs, I've seldom found a mass market engine that did not gain from properly remounting the head.

If the fit is not as free with the head torqued-in as it was with all loose, barring the TDC Squeak zone, of course, something is out of alignment. Most NIB engines I've looked into were not optimally torqued. Maybe over 50 years of playing this piano have endowed a delicacy to my touch?

Maybe I shouldn't encourage less experienced modellers to do what I do? Whatever... I'm more comfortable having done such a check, and others that can catch burrs, wear, bad fits, etc. before first run.

We get, pretty much, what we pay for. A mass-produced item is subject to risk from tolerance drift and variations in assembly. A highly developed and executed custom engine should not be, or we're wasting the money going there.

Hi Lou,

I am with you 100% on this. If my engine has been worked on by one of the engine gurus, I will only change the glo plug! No more disassembly is done. I trust them that they have reinstalled everything and that it is "clean" inside.

You have convinced me over the years to retorque the head of a NIB "stock" engine. I usually pull the back plate, also, just to check for cleanliness. So far, I usually enjoy good service from my engines.....

BIG Bear
RNMM/AMM

phil c · « **Reply #75 on:** July 21, 2013, 02:00:07 PM »

Not watching this thread lately, I'd have to go half way with Brett. Any new modern engine should be pretty clean inside. I would be silly to strip it down, especially if you haven't done it many times before and have learned how not to screw something up.

But even the best can leave a bit of something inside a new engine. The safest thing to do is to simply remove the backplate and plug and wash the engine out with kerosene or even just fuel and make sure the bearings show absolutely no signs of any grittiness or aren't absolutely free.

Be especially careful with castor oil in ABC engines. It is beginning to look to me that anything more than 3% is too much. I recently took apart an ABC stunt engine(Magnum 36) that was showing funky running problems. It had been run on 10N-11S-11C fuel for maybe 100 runs. Every surface inside, the piston, the outside of the liner, the head, the top and inside of the piston had varnish on it. It had never been run hard, or on too big a prop and never had a lean run.