Author Topic: Ruined my NEW BRODAK 40 (Read 10895 times)

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

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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.