Buyer beware!!! Dem Blue engines

[Paul Taylor]

OK,
Remember that new blue engine I won off da bay? Problem is it came without a glow plug and the engine binds at TDC when I turn it over. I pulled the back plate off and watched as I turned the engine over to see if I could tell where it was binding.
I can see when it gets to TDC that the rod still moving, but the piston stops moving.


Maybe the con rod it bent?

[Brett Buck]

OK,
Remember that new blue engine I won off da bay? Problem is it came without a glow plug and the engine binds at TDC when I turn it over. I pulled the back plate off and watched as I turned the engine over to see if I could tell where it was binding.
I can see when it gets to TDC that the rod still moving, but the piston stops moving.


Maybe the con rod it bent?

    With no plug most ABC/AAC engines will get tight at TDC due to the taper in the liner.

    Brett

[Dick Pacini]

The Brodak 40 is like that, as well as other brands I have read.  They have a "pinch" at the top that will open up upon proper break-in and operation.  I recall the instructions say to flip past it, don't roll it over slowly.

[johnbyrne]

At first I thought just a pinch in which case start it and break it in (have seen this on LA 46s) but that sounds a bit different.   Sounds like a tear down may be in order.

[johnbyrne]

And don't turn it over dry

[Dennis Moritz]

Pinch at the top when new is normal for these engines. A certain amount of play at top dead center may not be significant. The pinch will wear in during break in. Break the engine in with a smaller prop, 11/4, perhaps even 10/4 and get it up to operating temperature. A (slightly)  rich two stroke should work with the smaller prop. You want to break the engine near rpm that it will operate. The smaller prop will allow you to hit the rpm without over loading a new engine breaking in. It's also possible that the rod bearing has been ovaled. This can happen when an engine with a pinch (modern plated engines are set up that way) is turned over and over when dry. Which is one reason I stopped buying ebay engines. Too many anomalies. New(?) in box engines that looked new, appeared to be new, but had some weirdness about them. On the positive side, I have run engines that did what yours is doing, appeared to have some issue with the conrod bearing, the slight play at top dead center that you noticed. These engines have held up very well. I have run them for years.

[Paul Taylor]

This is not a pinch at TDC... this is binding.
I think the pistion pin is bent. My guess is the engine was stuck and he forced it free.

[Rafael Gonzalez]

This is not a pinch at TDC... this is binding.
I think the pistion pin is bent. My guess is the engine was stuck and he forced it free.

Hopefully is not an AVISTAR...   

 

[Dan Bregar]

A suggestion.  Heat the top of the cylinder up with your monocote heat gun for a couple of minutes and see if the bind goes away. That should tell you what's up. 

[Garf]

I bought a total of 3 FP 35 steel engines from our friendly auction house. One had a strange bind in the engine. Turned out to be a bent rod. I have no idea how that happened.

[Dennis Moritz]

See if you can get it apart. There are Teflon pads on the ends of the piston pin. Watch out for them. If the engine was advertised as new and there is a binding problem, it is reason enough to return the engine. Can you return the engine. I have done that a few times when engines were damaged, or in other ways not as advertised. I purchased an engine that was advertised as used with good compression and a good runner. The engine did not have good compression. When I disassembled it to take a look, I found areas where the nickel plating had peeled. The seller squawked but I told him he could look for himself, I'd be glad to send him the pieces. Send me the money back or not. But that the engine was no use to me. Of course parts can be useful, but in this case the engine was so whupped, outside of the backplate, nothing much to salvage.

[Paul Taylor]

I have opened a case with ebay just to CMA. I have two weeks to work with the seller to get some type of resolution.
It was advertised as NEW. It is damaged in my mind.

I will let this engine sit until I hear back from the seller.


Stay tuned..........

[Brian Hampton]

I've never owned a blue engine but some years ago a friend of mine bought one and asked me to run it in for him. It felt totally weird in that most of the time when trying to start it the piston would lock extremely tight at TDC then be nice and free for another one or two flicks before going back to locking up again. I managed to start it once where it seemed to run OK but on the next attempt to start went right back to the lock, free up, lock thing. I gave him the option of tearing it down to see what the problem was or sending it back under warranty. He sent it back and a week later it was returned with a note saying they'd run it and that there was nothing wrong with it. However, it felt like an entirely different engine so they most certainly did something with it but didn't want to admit that an OS could have a problem. Something like back in the days when engines were being returned for peeling and blaming it on operator error but fixing them because "we're such nice guys".

[W.D. Roland]

My experience with ABC engines were mainly K&B 6.5 in Fast Rat.
The first one received pulled the plug, back plate, All was spotless. turn it over by hand. Whoa, no way!
Mounted prop, turn over, WHAT THE HELL IS THAT BIND AND HORRIBLE SQUEAK!?!?!
Called John Broadbeck(?) after lapping didn't help. Think it nearly gave him a heart attack when I told him I tried
lapping it and then he gave me ABC lessons an the jigging,boreing, fitting, short version 'that's the way it supposed to be.'
When cold-bind Hot- no bind.
When the bind(cold) went away so did power and hot start.

Me? I would heat with gun or propane and see if it goes away....if so all is problem ok.

Do not never ever run rich like iron engine or there will not be enough expansion to have it a Hot Fit
and wear will be rapid. Fuel, prop that you plan to run and run it. 1st run possibly just backed off peak+ if it makes you feel better.

That's real ABC, No telling what your being sold now other than from others post seem quality control in fit
is a problem.

[Paul Taylor]

http://stunthanger.com/smf/index.php?topic=25390.0