News:


  • April 12, 2021, 12:15:55 AM

Login with username, password and session length

Author Topic: Brodak MKII .049 C/L Need Help  (Read 2158 times)

Offline Allan Leonard

  • A&P Mech
  • Trade Count: (0)
  • Ensign
  • **
  • Posts: 28
Brodak MKII .049 C/L Need Help
« on: May 31, 2018, 01:23:02 PM »
Ok I'm sure this has been addressed ad nauseam and I've tried my own research. I have a call into Brodak and they will be getting back to me. In an attempt to start the suggested break-in I can't get it to START. I have fuel, I have air, I have compression and I have ignition. I first worked from 2 turns open from seated. I have since worked from seated to open to the point of released spring tension in 1/4 turn increments. This is what I get: It will fire on almost every flip and on 3 occasions it ran for about a second but at very different needle settings. I can firmly seat the needle and it will continue to fire on every flip. This has me concerned, which I will get to. The tank feeds with gravity to the NVA so there is no fuel restriction. Propping at level, slightly nose-up to slightly nose-down matters not. Turning over by hand I can feel the ignition bump. The included instructions warn AGAINST using a starter but the web site suggests it will shorten the break-in. I'm thinking I need the rpm help the starter would give. I've given momentum some thought by starting with  a 5-3 3 blade then a 6-3 2 blade and a 6-3 3 blade no difference. This, though, has me concerned: With the needle firmly seated it will continue to fire. Not just a few times but what seems like all day. I gave the fuel line the "suck and blow" test and it's not seated. THE NEEDLE VALVE THREADS ARE BOTTOMING OUT IN THE ASSEMBLY. It is not the spring binding because I removed that.

Any thoughts, suggestions?

PS: Anticipating the questioning on my choice of engine just let me say that it's mounted on a profile F4F and I find the beam mount more pleasing to my eye.

Thanks in advance.


Advertise Here

Offline Fredvon4

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2118
  • Central Texas
Re: Brodak MKII .049 C/L Need Help
« Reply #1 on: May 31, 2018, 01:56:12 PM »
Many of these newer engines do have a LOT of TDC pinch.... notable many Norvels

I use a heat gun to heat the head as I bench run them

if I recall correctly many of the smaller engines can also have a very tight Crank to case clearance....I polish all mine from new

also on many of the newer small engines I bias my fuel to be more synthetic and less castor and in the 20% oil area

Full disclosure..I do not have any Brodak .049s....mostly Norvel, Fora
"A good scare teaches more than good advice"

Fred von Gortler IV

Offline Gary Dowler

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 981
Re: Brodak MKII .049 C/L Need Help
« Reply #2 on: May 31, 2018, 04:08:47 PM »

Allan, 1/2A's can be very aggravating.  Lighter fluid as a primer works great. If your fuel isn't hot enough you will have problems getting things going. What is your nitro content?   I've never had a Brodak motor, but the Cox motors work best with nitro over 20%. Also the Cox motors couldn't care much less about synthetic oil, they thrive on Castor.  Again, I don't know how the Brodak motors compare, but have fun trying to keep a Cox engine running on less than 20% castor. Some individual engines might, but the breed as a whole likes more. A recent test I did with multiple Cox .049's confirmed this. At 16% castor none would run out a tank (25% nitro). At 20% only one effort in 4 got a full run. 22% saw all engines make full runs every try. At 24% or above the only difference seemed to be more mess.

The suggestion about warming it up with a heat gun has merit. Give it a try. Just use enough nitro.

Gary
Profanity is the crutch of the illiterate mind

Offline bob whitney

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1925
Re: Brodak MKII .049 C/L Need Help
« Reply #3 on: May 31, 2018, 05:52:29 PM »
it sounds like the old CS problem where the needle wouldn't close completely.  dis connect the fuel line and see if it runs out the prime .prime it  three or 4 times and then hook fuel line back up prim as before .if it floods than the needle valve needs to be modified  one of the FF guys had a fix for the CS, could probly do the same for the Brodak
rad racer

Offline 944_Jim

  • 21 supporter
  • Trade Count: (0)
  • Captain
  • *
  • Posts: 481
Re: Brodak MKII .049 C/L Need Help
« Reply #4 on: May 31, 2018, 07:50:07 PM »
I don't have a Brodak either, but my Norvels liked a smaller prop for break-in. Either cut the prop down, or go with a smaller one. Then you can get rpms up while running rich enough to keep from over-spinning and over-heating.

My Norvels won't gravity feed without drowning. Neither will my Cox reedies.
My one AP .061 runs great with the tank level with the spraybar and muffler pressure.

Bench running cures a lot of break-in problems, like tank height, and tight fit. It sure makes turning-over the engine easier than while holding an airframe!
YMMV

Offline Motorman

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 6278
  • Millville NJ PDQ Flying Clown Country
Re: Brodak MKII .049 C/L Need Help
« Reply #5 on: May 31, 2018, 09:45:02 PM »
It sounds like it's flooded bad which is a common problem if you don't usually run 1/2a engines. Disconnect the fuel line, let it dry out then get use to giving it tiny primes and running them off. The fuel tank should not gravity feed the engine or it will easily flood. If it has a muffler take it off until you get it running. On Cox we use to blow in the exhaust port to dry it out. If you're sure it's not flooded it might still have allot of oil in it so not using an electric starter is good advise.
Remove victim to fresh air

Offline Joe Ed Pederson

  • 2019 supporter
  • Trade Count: (0)
  • Commander
  • *
  • Posts: 326
Re: Brodak MKII .049 C/L Need Help
« Reply #6 on: June 02, 2018, 02:59:57 PM »
Fred,

When I was in High School (1970) a friend bought a K&B Stallion .35.   It would do the things your engine is doing.  It would fire but we couldn't get it to run.  His new engine had stronger compression than the McCoy .35s we were more familiar with.  As a last resort, being kids, instead of seeing if we could get head washers to lower the compression we just loosened the head screws evenly.  With the reduced compression we got her to run and in a few tanks we tightened the head screws back up and she was easy to start and ran consistently after that.

You didn't say if the compression seemed excessive or really strong, but your problems gave me the chance to reminisce about a time long ago and how a friend and I solved a problem.


Joe Ed Pederson

Offline kenneth cook

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1320
Re: Brodak MKII .049 C/L Need Help
« Reply #7 on: June 02, 2018, 08:33:28 PM »
               While Joe's comments are very relevant, the issue is more likely that the taper in the sleeve is not allowing you to flip the engine properly and allow it to run . Unlike a iron piston assembly mentioned, the issue here is more the fit of the taper not compression.  The Brodak MK II is a high quality engine for the $$$$$. You don't typically see AAC construction in engines until your triple the price the Brodak offering is. You need to heat the cylinder a bit prior to flipping. A Monokote gun or paint stripping gun works very well for this. The case however will cool very rapidly and the heat source needs to be in close proximity. Keep your tank at or slightly below the needle valve centerline to avoid flooding  and keep your fuel line as short as possible. You should see the fuel coming up the line after a few hand chokes. Heat the cylinder and assume your starting procedure. Once running, don't run this engine rich. It should be in a a wet 2 cycle. You want the assembly to get up to operating temperature within a minute or two and then shut it off. The engine should be allowed to completely cool prior to running again and this procedure is going to be needed at least a dozen times before it starts offering easier and more reliable runs.

Offline Wayne Collier

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 473
Re: Brodak MKII .049 C/L Need Help
« Reply #8 on: September 16, 2020, 09:22:56 PM »
Hey, I know this is an old thread. I found it with the search.

Iím having the same problem described in the first post of the thread.

Relatively new Brodak.049 MK II. Engine fires on almost every flip but doesnít pick up and run. Needle setting or prime doesnít seem to make any difference.  I can see fuel coming up the line if I choke the venturi with my finger. I tried induction and exhaust prime. Same difference. Considered giving it a shot of ether but didnít want to break anything.

Does anyone have information on how to solve this?


Wayne Collier     Northeast Texas
<><

never confuse patience with slowness never confuse motion with progress

Online Brett Buck

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 11792
Re: Brodak MKII .049 C/L Need Help
« Reply #9 on: September 16, 2020, 10:27:45 PM »
Hey, I know this is an old thread. I found it with the search.

Iím having the same problem described in the first post of the thread.

Relatively new Brodak.049 MK II. Engine fires on almost every flip but doesnít pick up and run. Needle setting or prime doesnít seem to make any difference.  I can see fuel coming up the line if I choke the venturi with my finger. I tried induction and exhaust prime. Same difference. Considered giving it a shot of ether but didnít want to break anything.

Does anyone have information on how to solve this?

  Get a Medallion 049. This is very similar to what Uncle Jimby and I found with several copies of a Brodak 049s  - we got one of them to run, weakly, for about 30 seconds (after an immense amount of fiddling) but couldn't ever get it started again.  It feels OK, OK compression and not bound up, but just doesn't appear to want to meter fuel.

     Brett

Offline Dan Berry

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 760
Re: Brodak MKII .049 C/L Need Help
« Reply #10 on: September 18, 2020, 10:04:58 PM »
Do what Brett said.

Offline kenneth cook

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1320
Re: Brodak MKII .049 C/L Need Help
« Reply #11 on: September 20, 2020, 05:19:18 AM »
           I really enjoy my Brodak MK II. The engine runs quite well . I feel it's right on par with a Cox Black Widow but it has reliability and consistency. When new, my engine wouldn't flip due to it being too tight. This was in the case to crankshaft fit. My now retired flying partner honed the case and I never looked back. I also had some tightness in the driveplate to the front of the case when the prop was fully tightened. A little sanding and all was good. The directions suggest low nitro fuel and I skipped that and went to my go to Sig 25% nitro which woke it up considerably. Not only did it start easier, it also turned up a APC 5x3 to 20k.

Offline Wayne Collier

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 473
Re: Brodak MKII .049 C/L Need Help
« Reply #12 on: September 21, 2020, 09:02:09 AM »
The one I have doesnít have any tight places at all. Turned easy right out of the box. Fires on almost every flip. Just never picks up and runs. I usually use 15% nitro in everything. I ordered some higher nitro fuel. Weíll see what that does.
Wayne Collier     Northeast Texas
<><

never confuse patience with slowness never confuse motion with progress

Online Brett Buck

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 11792
Re: Brodak MKII .049 C/L Need Help
« Reply #13 on: September 21, 2020, 10:04:01 AM »
The one I have doesnít have any tight places at all. Turned easy right out of the box. Fires on almost every flip. Just never picks up and runs. I usually use 15% nitro in everything. I ordered some higher nitro fuel. Weíll see what that does.

     Sounds exactly like mine, it feels fine, decent compression and free, feels good,  but just pops. The one brief run I got on Jim's engine was on Cox Racing fuel. I have seen one converted to run some version of a button head, with some modifications to the intake, that ran fine. I presume that the big problem is the intake, but I haven't seen any need to spend a lot of time figuring out how to fix it.

     Brett
« Last Edit: September 21, 2020, 10:42:37 AM by Brett Buck »

Online Brett Buck

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 11792
Re: Brodak MKII .049 C/L Need Help
« Reply #14 on: September 21, 2020, 10:55:24 AM »
You didn't say if the compression seemed excessive or really strong, but your problems gave me the chance to reminisce about a time long ago and how a friend and I solved a problem.

   That's kind of interesting - one wonders of the head clearance on the .049s is set extremely close to make up for the fact that at least one version of the Brodak engine uses conventional plugs. The key finding that Cox made was that you cannot effectively use a conventional separate plug in these tiny engines because there it too much wasted combustion chamber volume and extremely rough surfaces. That's why the Cox engines were so remarkably more powerful than any of it's predecessorts, and why any decently powerful small engine uses a glow head or glow button.

    It would be even worse if the people that made it in an Iron Curtain country also tried to make it run on FAI fuel, that would require more compression yet. With a conventional plug you would have to have almost no clearance, the volume of the recess in a conventional plug is probably most of it.

    The good-running Brodak engines I have seen had been modified to use head buttons, with compression set appropriate to conventional fuel.

     Brett

Offline bob whitney

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1925
Re: Brodak MKII .049 C/L Need Help
« Reply #15 on: September 21, 2020, 11:07:42 AM »
even though u will probly run a 5 in prop try starting it with a 7 in prop to get some flywheel affect  .if it will run for short burst;s thatn u shouldnt need to worm it up any more . like they say, pull the fuel line off and run the prime out a few times then hook up fuel line ,close needle  if it go's rich u have a defective needle assby, the Free Flight guy, Dugh Galberth (spelling ) has a fix for it
rad racer

Offline Fredvon4

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2118
  • Central Texas
Re: Brodak MKII .049 C/L Need Help
« Reply #16 on: September 21, 2020, 11:14:29 AM »
http://www.the-printer.net/DookCat.html

Head adapters for Nelson Plugs
"A good scare teaches more than good advice"

Fred von Gortler IV

Offline kenneth cook

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1320
Re: Brodak MKII .049 C/L Need Help
« Reply #17 on: September 21, 2020, 01:19:26 PM »
           A head adapter won't work on a Brodak MK II. You need to make a new head.

Offline Fredvon4

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2118
  • Central Texas
Re: Brodak MKII .049 C/L Need Help
« Reply #18 on: September 22, 2020, 10:20:43 AM »
you are correct... I must have got interrupted and failed to note Doug's NVAs Bob Whitney was talking about
"A good scare teaches more than good advice"

Fred von Gortler IV

Online Reptoid

  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 277
Re: Brodak MKII .049 C/L Need Help
« Reply #19 on: September 22, 2020, 03:20:54 PM »
http://www.the-printer.net/DookCat.html

Head adapters for Nelson Plugs
Doug Galbreath is no longer in business
Regards,
       Don
       AMA # 3882

Offline Fredvon4

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2118
  • Central Texas
Re: Brodak MKII .049 C/L Need Help
« Reply #20 on: September 23, 2020, 08:21:09 AM »
Sadly, I just found that out yesterday. I had a bunch of his stuff that I have since given or sold
"A good scare teaches more than good advice"

Fred von Gortler IV

Offline Wayne Collier

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 473
Re: Brodak MKII .049 C/L Need Help
« Reply #21 on: September 30, 2020, 12:45:25 PM »
Looked inside the Brodak.049. Removed an extra head gasket. Upped the nitro. No difference. Thinking Iím gonna cut the loses and rework the nose of the plane for a reedy that is running. May put the Brodak in the classifieds with a good explanation of why Iím done with it?  Very few engines have frustrated me to the end of my patience.
Wayne Collier     Northeast Texas
<><

never confuse patience with slowness never confuse motion with progress

Online Brett Buck

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 11792
Re: Brodak MKII .049 C/L Need Help
« Reply #22 on: September 30, 2020, 03:55:29 PM »
Looked inside the Brodak.049. Removed an extra head gasket. Upped the nitro. No difference. Thinking Iím gonna cut the loses and rework the nose of the plane for a reedy that is running. May put the Brodak in the classifieds with a good explanation of why Iím done with it?  Very few engines have frustrated me to the end of my patience.

   My impression was that the problem was in the intake/induction system, rather than any provblem with compression or piston fit.

    A Medallion should  go in there with minimal change.

     Brett

Offline kenneth cook

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1320
Re: Brodak MKII .049 C/L Need Help
« Reply #23 on: September 30, 2020, 04:28:15 PM »
          I had mine on the bench APC 5x3 Fitz Rocket 24 fuel which is probably too much castor  and it's certainly doing well and better than a Medallion.

Online Dan McEntee

  • 2015
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4551
Re: Brodak MKII .049 C/L Need Help
« Reply #24 on: September 30, 2020, 05:50:34 PM »
Looked inside the Brodak.049. Removed an extra head gasket. Upped the nitro. No difference. Thinking Iím gonna cut the loses and rework the nose of the plane for a reedy that is running. May put the Brodak in the classifieds with a good explanation of why Iím done with it?  Very few engines have frustrated me to the end of my patience.

  Have you tried another needle valve?  It may be drawing fuel but not enough. I have seen other engines with needles like these where the needle was mis-shaped or pressed into the knurled knob too far. If it's running on a prime, it should run if it is getting enough fuel. There might be some sort of swarf inside the spray bar, or the hole down the venturi plugged with something
   Type at you later,
  Dan McEntee
AMA 28784
EAA  1038824
AMA 480405 (American Motorcyclist Association)

Offline Howard.Y

  • Trade Count: (0)
  • New Pilot
  • *
  • Posts: 17
Re: Brodak MKII .049 C/L Need Help
« Reply #25 on: September 30, 2020, 06:11:27 PM »
Have you checked to see if there's excessive play between crank and crank case.

Online Brett Buck

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 11792
Re: Brodak MKII .049 C/L Need Help
« Reply #26 on: September 30, 2020, 08:05:22 PM »
Looked inside the Brodak.049. Removed an extra head gasket. Upped the nitro. No difference. Thinking Iím gonna cut the loses and rework the nose of the plane for a reedy that is running. May put the Brodak in the classifieds with a good explanation of why Iím done with it?  Very few engines have frustrated me to the end of my patience.

   You said you contacted them, what did they say?  Brodak has always been very good about replacing things if you are not having good results.

     Brett

Offline Wayne Collier

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 473
Re: Brodak MKII .049 C/L Need Help
« Reply #27 on: September 30, 2020, 10:33:53 PM »
   You said you contacted them, what did they say?  Brodak has always been very good about replacing things if you are not having good results.

     Brett

Actually havenít contacted them at this point. Thought Iíd check here first in case someone who has experience with this type engine might share something Iím missing. Didnít want to complain that I got a dud if the problem is me.  This one just feels like low compression. I also suspect the needle valve assembly.
Wayne Collier     Northeast Texas
<><

never confuse patience with slowness never confuse motion with progress

Online Brett Buck

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 11792
Re: Brodak MKII .049 C/L Need Help
« Reply #28 on: September 30, 2020, 11:34:10 PM »
Actually havenít contacted them at this point. Thought Iíd check here first in case someone who has experience with this type engine might share something Iím missing. Didnít want to complain that I got a dud if the problem is me.  This one just feels like low compression. I also suspect the needle valve assembly.

   The problem isn't you.

     I would at least ask them what can be done to resolve this before giving up completely. The Brodak quality control plan seems to be to cede the screening to the user, and then give very generous support if something goes wrong.  When everything works, then it's a win-win for all involved, the price is lower with the same profit. When it doesn't, then they replace it. I don't know if that is more profitable than paying for screening up front and then having to charge more, but it doesn't do then any good to have dissatisfied customers in this *tiny* market.

    Brett

Offline Dennis Toth

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2896
Re: Brodak MKII .049 C/L Need Help
« Reply #29 on: October 01, 2020, 06:40:03 AM »
Wayne,
A couple things to check, first check that there is not a leak in the backplate or any place that would cause a leak of base compression. This kind of leak will keep the engine from blowing the fuel up into the combustion camber and it won't run right if at all. Second it sounds like the NVA is not shutting off if you seat it, one way to see if this is a problem is to lower the tank so that the tank top is below the spraybar height to stop any siphoning, if it runs this way you need either a new needle or whole NVA assembly. Last make sure your ignitor is fully charged to give the plug full heat, glowing bright. Sometime a weak ignitor will let it fire but as soon as a fuel charge hits it, it goes cold and will not keep it going.

Best,    DennisT

Offline Dan Berry

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 760
Re: Brodak MKII .049 C/L Need Help
« Reply #30 on: October 01, 2020, 06:39:34 PM »
Mine seized the piston trying to break it in.
I put it away for safekeeping.

Online Brett Buck

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 11792
Re: Brodak MKII .049 C/L Need Help
« Reply #31 on: October 01, 2020, 08:23:52 PM »
Mine seized the piston trying to break it in.
I put it away for safekeeping.

   If by that you mean, you dropped a heavy safe on it from a high building, then kudos.

    As luck would have it, we are in the window for submitting proposals for "Demonstration Events" for next years Hurl. Write a proposal consistent with section 7, paragraphs A-AD, and AG, submit through the usual Hurl channels, and we will see!

     Brett

Offline Dan Berry

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 760
Re: Brodak MKII .049 C/L Need Help
« Reply #32 on: October 02, 2020, 05:08:41 PM »
   If by that you mean, you dropped a heavy safe on it from a high building, then kudos.

    As luck would have it, we are in the window for submitting proposals for "Demonstration Events" for next years Hurl. Write a proposal consistent with section 7, paragraphs A-AD, and AG, submit through the usual Hurl channels, and we will see!

     Brett

Ha!
It is safe where it is.
I'm thinking that the esteemed Wile E. Coyote should be the guy writing that proposal.

Online Dan McEntee

  • 2015
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4551
Re: Brodak MKII .049 C/L Need Help
« Reply #33 on: February 22, 2021, 03:13:28 PM »
  Well I'm raising this thread back up because I bought the engine from Wayne and he had it for sale for along time. It sat in tne exact place I put it when it arrived  last October I think it was. Work,  life in general, and Mr Covid all got in the way of me trying to start it. Well, I went to the post office today and it was a lovely 55 degrees out and bright sunshine! I got home and couldn't bear the thought of going inside so I went to the garage, saw that it was 10 or 15 degrees colder in there than outside, so I opened up the door to let some sunshine and heat in!
  There on the pile by where I store my flying gear was the box with the Brodak .049 in it. I thought, "Today is the day!"  I looked it over a bit, and opened the needle valve a few turns and tried to blow air through it and didn't feel anything. I turned the needle all the way out and could see a bit of sunlight through the spray bar, gave it another toot of air and the hole looked bigger. I put the needle back in and opened several turns.  It had a 7-3 APC prop on it so I left it there. I have a collection of EZ-Just type test stands, grabbed a small one for small engines and mounted it up. I got my starter box out, fuel and syringe and gave it enough fuel in the venturi and exhaust to loosen it up. I hooked up the battery to the glow plug, then hit it with the starter and it barked a little bit. A couple of tries more and it ran the prime out. Then I strapped one of the tanks Wayne sent me with the engine to the test stand and hooked it up with some fuel line.  I choked it and applied the starter and it was obviously flooded at that point. Pinched off the fuel line and flipped and cranked it a bit to clear the prime which it did and ran for a few long seconds and ran out the flood. Then I closed the needle, burped it again, opened the needle about 3 or 4 turns and hit it with the starter again. It came to life and settled into a rich four stroke. I leaned it out a bit to a higher four stroke seating and it needled vary nicely. It ran out the tank, (maybe an ounce) and filled the tank for another try. This time i didn't choke it and just hit it with the started and it fired to life right away. I needled it up to where it was breaking back and forth from 4 to 2 stroke and back again and put a tach on it and saw 12,800 RPM with the 7-3 APC. I thought that was pretty healthy myself. It rand that tank dry so I proceeded to clean things up and put stuff away because the sun had gone back behind the house and it was breezy and getting cooler.
    One thing I noticed while it was running the second time , was really small air bubbles coming out where the post f the glow plug went into the ceramic seal. This was barely noticeable, but I could blow or wipe them away and they would return. I'm not sure what type of plug it is but may have been part of Wayne's problem. I also think there may have been some sort of blockage in the spray bar. I will replace the glow plug once I get around to it and see if I have something hanging in the garage to mount it on and fly it. If it happens to match the tank mount for a Norvel  or the red tank mount for a Cox TeeDee .049 that may make this job easier. I don't know the exact cause of Wayne's problems But think it was just a series of really small events and  happened to solve them right away.
  Type at you later,
   Dan McEntee
AMA 28784
EAA  1038824
AMA 480405 (American Motorcyclist Association)

Offline Wayne Collier

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 473
Re: Brodak MKII .049 C/L Need Help
« Reply #34 on: February 24, 2021, 12:40:42 AM »
Glad you cracked the code.  I feel better about the whole thing now. Actually, that is the only model airplane engine I ever gave up on. The glow plug was the one that came with the engine. I'm guessing that the spray bar may have been part of the problem? When I could see light through it I didn't check further. If you used an electric starter, that may have been a help. I didn't try one. I'm curios what fuel you used.
Wayne Collier     Northeast Texas
<><

never confuse patience with slowness never confuse motion with progress

Online Dan McEntee

  • 2015
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4551
Re: Brodak MKII .049 C/L Need Help
« Reply #35 on: February 24, 2021, 11:30:55 AM »
Glad you cracked the code.  I feel better about the whole thing now. Actually, that is the only model airplane engine I ever gave up on. The glow plug was the one that came with the engine. I'm guessing that the spray bar may have been part of the problem? When I could see light through it I didn't check further. If you used an electric starter, that may have been a help. I didn't try one. I'm curios what fuel you used.

   Hi Wayne;
    I could see light through the spray bar also, just didn't see like it was a round and clear as it should be. Could have been a small piece of swail from the manufacturing process. I had a spray bar in a OS.32 that suffered the same affliction. The engine just didn't act right so I pulled the spray bar and took a look through it. I could see something in there, so I ran a piece of wire through it and tried to catch whatever came out in my hand but didn't see anything. Put it all back together and it has been like a Swiss watch ever since. For fuel, I just grabbed a quart bottle of some old Redmax 20% nitro , 18% oil fuel that was sitting on a bench. have no idea how old but it's OLD and it has run in some Norvel engines I have tried it on. If these are anything like a Norvel, they ought to run on just about anything. I'm so "cheap and thrifty' that rather than waste the plug, I'll probably just dab some JB-Weld around the base of the post to try and seal it since it ran like it was.
   I thought I remembered you stating that it wouldn't even run out a prime, and I found that puzzling. That was the first thing I tried, running a prime through it, and when it ran that out for about 2 or 3 seconds, I figured if I had a decent tank set up it would just e a matter of finding the needle setting f or start up. What fuel were you using? Maybe that might have been a part of the problem ???
   Type at you later,
    Dan McEntee 
AMA 28784
EAA  1038824
AMA 480405 (American Motorcyclist Association)

Offline Wayne Collier

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 473
Re: Brodak MKII .049 C/L Need Help
« Reply #36 on: February 24, 2021, 12:27:18 PM »
I started with Brodak 15% nitro/ 20% oil. It would pop on almost every flip but just never ran. Also tried Brodak 25% and 35% nitro. No noticeable difference. After I sent the engine to you I tried using the Brodak 15% nitro in an OS .25. It was hard to start and didnít run super great. I refilled the OS with the power master 15% nitro/ 18% oil that I generally use. The.25 popped right off and ran the tank dry with no issues.
Wayne Collier     Northeast Texas
<><

never confuse patience with slowness never confuse motion with progress

Online Dan McEntee

  • 2015
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4551
Re: Brodak MKII .049 C/L Need Help
« Reply #37 on: February 24, 2021, 07:06:05 PM »
I started with Brodak 15% nitro/ 20% oil. It would pop on almost every flip but just never ran. Also tried Brodak 25% and 35% nitro. No noticeable difference. After I sent the engine to you I tried using the Brodak 15% nitro in an OS .25. It was hard to start and didnít run super great. I refilled the OS with the power master 15% nitro/ 18% oil that I generally use. The.25 popped right off and ran the tank dry with no issues.

    Well then I would cast a suspicious eye towards the fuel. Especially after trying it in other engines. I have run a lot of old fuel in my time and really have been lucky with it. I make a lot of effort to store it in a cool, dry area and stable temps and in the shipping boxes off the floor and have had no problems. I can remember one jug of fuel go bad on me and it was from one flight to the next, about half way through the jug. Couldn't get it to run in anything and in that instance it was a relatively new jug. I've opened 40 year old cans of Cox fuel and it started and ran first flip until it was gone. It's just a variable that needs to be checked and make sure you have some known good working fuel on hand.
    Type at you later,
    Dan McEntee
AMA 28784
EAA  1038824
AMA 480405 (American Motorcyclist Association)

Offline Dave Hull

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1223
Re: Brodak MKII .049 C/L Need Help
« Reply #38 on: February 24, 2021, 07:50:28 PM »
Thanks for finishing the story, Dan and Wayne. That kind of info is always helpful....

Shortly after I bought a set of the CS .049s (the speed version, not the sport motor), some 20 years ago I realized:

--The needle valves were poor, and would not close. And the collet nut setup needed help, the needle was wobbly in the spraybar, and no doubt leaking;
--They would not hand start with any prop that was of suitable size. I think I managed it once in plenty of trying. And, you needed a high rpm 1/2A-style starter. These were high rpm gems that used little fiberglass toothpicks;
--They used a Nelson plug, but it needed to be driven pretty hard if you wanted a quick start. A weak battery was the kiss of death, or perhaps a guarantee of IC dormancy.

So I got in touch with Doug Galbreath to see if he had a needle valve assembly that would fit. He did not, but said if I sent him the engine, he would see about getting something made that would fit. So that's what we did. They work fine. So the right needle, a hot plug, some fresh fuel, and an electric finger made these workable engines. I suspect quite a few of the non-Cox modern engines have similar concerns and issues.

The Divot

Online Dan McEntee

  • 2015
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4551
Re: Brodak MKII .049 C/L Need Help
« Reply #39 on: February 25, 2021, 10:35:03 AM »
   I try to apply the simplest solutions first. If I had the engine first, I would have tried other fuel some where early on. I haven't taken the head off to see what t he combustion chamber looks like bit it can't be huge, most of that taken up with the standard size glow plug. I wonder if this is the reason why most successful 1/2A engine designs use a glow head instead of a standard glow plug. I think Brett mentioned something about overall clearances in the head? I'm not talking about for high performance, just so the engine starts easy and runs consistently?  This is the first one of these I have ever held in my hand, but I think I recall the first generation of these was less than a success? I would be interested in hearing the whole story.
   Type at you later,
    Dan McEntee
AMA 28784
EAA  1038824
AMA 480405 (American Motorcyclist Association)

Offline kenneth cook

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1320
Re: Brodak MKII .049 C/L Need Help
« Reply #40 on: February 26, 2021, 02:19:21 PM »
             Manufacturers knew over 50 years ago about the benefits of a glow head. This engine should've been designed with the standard Cox thread therefore you could've used a Cox plug , Norvel, or the Merlin style Glo Bees. It's a considerable power loss. The crankshaft timing of the MK II is similar to a Cox Medallion and a TD style crank should've been made as well. The engine has a lot of hidden power in my opinion. I've seen the engine run with a  Nelson head assembly which offered a fair amount of performance. The engine was designed with the beginner in mind which are far and few these days. I still enjoy mine and it's a terrific runner nowadays. It took some running in though.  The Brodak MK 1 CS version was a real piece of crap. Mine had a hole all the way through the case due to poor casting. The crankshaft looked like it was made with stone tools and it wouldn't run with the stock head. I drilled out the threads for a Merlin drop in plug and it finally started. It never put out any potential that was impressive enough for me to keep the engine. Cox was offering Sure Starts for $8 which outperformed the CS .061 that I owned.

Offline Joe Ed Pederson

  • 2019 supporter
  • Trade Count: (0)
  • Commander
  • *
  • Posts: 326
Re: Brodak MKII .049 C/L Need Help
« Reply #41 on: February 26, 2021, 06:51:59 PM »
        I still enjoy mine and it's a terrific runner nowadays. It took some running in though. 

Kenneth,

Is your MK II running terrific with the regular glow plug as designed and sold or with a Nelson head?

Thanks,
Joe Ed Pederson

Offline kenneth cook

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1320
Re: Brodak MKII .049 C/L Need Help
« Reply #42 on: February 27, 2021, 05:33:23 AM »
              Joe, I'm using my MK II with the stock configuration. Higher up in the post is a picture of me holding the tach on the engine when I first had it running with a APC 5x3 in which you can see the stock plug. I mentioned the Nelson plug because I got to witness one of these engine using one. I strongly feel that using a glow plug on a 1/2A engine is a real negative and I wouldn't of opted for doing so. At the time of the release of this engine, a few plug  options were available which would've significantly improved starting and performance. Even a turbo plug would've been a considerably upgrade as it would've offered Nelson plug performance.

 The Nelson head I witnessed was custom made for the engine. No one offers a Nelson head for the Brodak MK II. Henry Nelson did offer a Nelson head for the Brodak MK 1 CS version. They were almost $40 which adds considerable cost to a turd of a engine. He didn't make many but  they added considerable rpm's.  I had the opportunity to purchase the Brodak MK II Nelson head engine and didn't take it. I really wish I did. What I've noticed with those that own this engine including myself is that the engine is very problematic to start initially. My son put it on the bench last weekend and the temp was 20 deg. We just made our own 1/2A fuel and wanted to give it a run. The engine started in 3 flips . I truly enjoy running this engine. I was even wondering if a Norvel muffler could be adapted to fit as the size looks very close.

Offline Joe Ed Pederson

  • 2019 supporter
  • Trade Count: (0)
  • Commander
  • *
  • Posts: 326
Re: Brodak MKII .049 C/L Need Help
« Reply #43 on: February 27, 2021, 10:21:02 AM »
Thanks, Kenneth.

My apologies for not having looked closely at the picture you posted earlier in the thread.

Joe Ed Pederson


Advertise Here
Tags: