Mutunug .61 ABC BB engine

[Crash]

Purchased this engine on a well known auction site. Looks brand new and came in the original box with info sheets and owners manual. Hand turned it without a glow plug and the piston binds near TDC. Removed the head and there appears to be no damage to piston or liner. Seller said it had only been run on test stand for break-in. Should I attempt to start it send it back? :?:

PS: Something clicked and I remembered there was something different about ABC engine break in. "TAPERED CYLINDERS D___ A__!"

[Frank Klenk]

Crash

The ABC engine, non ring does have a tapered cylinder. So with the piston at TDC there is what we call "pinch". You have it and that is good. Now as the engine breaks in you will notice the pinch is less severe. Also after running the engine and it is all warmed up you will also notice the pinch is gone until it cools. This too is normal. Some of the high performance engines have a LOT of pinch. So much so the engine will actually squeak at TDC. So, to solve that we warm the engine up (gently) with a heat gun or small torch and then fire them up. It makes things last longer.

Frank 8)

[Crash]

Thanks Frank. Sometimes it always helps to "read the instructions" on just about anything.

Another problem. Have a brand new Magnum GP 40 on a plane I built 15 years ago, flown once, successfully, and I accidentally knocked it off the work table and broke off one of the outside cooling fins on the head. How much will this affect the engines cooling pattern. Doubt if I can find a replacement.

Jim

[chiefss]

Absolutely zero effect on the engine

[Crash]

Thanks again Frank! I have a brother named Frank and he is a good guy too!

Thanks again,
Jim :)

Oops!! Sorry Chiefss didn't even notice you weren't Frank! I'm sure you are a good guy too! :oops:

[chiefss]

That's OK. There are a few that think I'm an A**hole but they are in the small minority. Ask Frank.

Bruce

[Crash]

I have been called worse!! People have said things like, " not saying he is but his mother ran out from under the porch and bit me on the leg"!

Jim :lol:

[Crash]

I have a Futaba 7 ch Conquest 72 mhz FM on Ch 50. Everything I read never says it is not legal, but I m not convinced. I can find anything that says it is and Futaba will not answer my inquiry.

Great radio, practically new. Got out of the hobby in the '80's but my son and grandson and granddaughter are draging me back.

Can anyone shed light on the subject?

Jim

[chiefss]

Jim,

go to this web site and look at "Please explain narrow band to me." It's Futaba's web site and according to this page and Futaba, ALL FM Futaba transmitters are narrow band. However, NOT all FM receivers are. The web page tells which Rx's are and which aren't.

www.futaba-rc.com/faq/faq-freq.html

I use several old (25 years+) G series Futaba FM radios and they are all legal. I have replaced the older Rx's with narrow band ones and they all meet narrow band specs. Also use AM G series that were upgraded and have the gold sticker on them. All are excellent radios. So were the Conquest series.

See, I really am a good guy.

Bruce

[Crash]

Bruce:

You are just full of it! Good information I mean... The plane with that system is a my son's house and I will call and see what receiver we have. If my memory serves me right we're ok.

I also have an old "Hobby Lobby" brand five channel that has been converted and proudly wears the gold seal. People look at me kind of strange when I pull that one out!

Thanks,
Jim

[chiefss]

Us A**holes are always glad to help out a fellow modeler. Don't bust it. Tower still sells a Futaba FM receiver that is compatible with your conquest transmitter. So does Hitech and I think Tower's FM receiver will work with it, too.

Bruce

[Crash]

"After Run" oil looks, smells and feels just like air tool oil...hummmmn..could there be something to this? :wink:

[Crash]

Back to Rusky/Chinese .61. On further examination, I discovered that this engine has a "high silicon aluminum alloy piston/w an aluminum alloy ring."

I don't know a lot about ABC Engines but this is the first one I have ever seen with a piston ring! Anyone have a slant on this?

Jim :roll:

[chiefss]

[quote="Crash"]"After Run" oil looks, smells and feels just like air tool oil...hummmmn..could there be something to this? :wink:[/quote]

Tower's and Prather's red after run oil looks and smells just like ATF. I use Marvel air tool oil and ATF for long term storage. Marvel Mystery oil for short term. It burns so the engine is easy to start even flooded with it. Also mix Mystery oil with ATF for long term.

[Crash]

Thanks Chiefss! Actuall the cost from Tower is comparable (minus shipping) but I have several air tools.... 8)

[chiefss]

Tower charges about 4 bucks for 4 ounces ofARO plus shipping. ATF is about 2 bucks a quart and air tool oil is about 3 bucks a quart. Marvel Mystery oil is about the same.

[Crash]

Tell you the truth Bruce, I didn't look as close as you did at the price. When you say ATF I am assuming you mean Automatic Transmission Fluid.

Jim

[chiefss]

Yup and I used to sell this stuff when I worked for Hobby Shack. I would quietly mention to a customer that ATF was much cheaper and just as good. Same for air tool oil and Marvel mystery oil.

[10%_nitro]

I had one of those .61s, front bearing seal leaked heavily on the 4th flight. It was a pretty heavy engine too.