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Old 11-16-2010, 08:26 AM   #1
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Default Somewhat seized engine?

I bought a bunch of nitro car parts from eBay, nothing great. There was enough pieces for 1 complete car and a bunch of spares. I'll sell it locally for a bit of profit. Anyhow, there was a spare engine, and the piston gets stuck about 3/4 of the way up. If the engine is assembled, I can force the piston to go around, however when the head is off, it just pushes the sleeve out, and I can't hold it in with my hand.

The piston and sleeve look fine to me, everything seems fine, without the sleeve, the piston is fine on the crankshaft. They're "Condor" buggies or something, pretty damn old, I believe they were made by HSP before they were even called HSP. Is there something I should try before condeming this engine?
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Old 11-16-2010, 08:35 AM   #2
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Id try bolting it all together, put in the car and heat the motor up to around 100c with a heat gun and try and fire the sucker up!

What have ya got to lose?


I dont know the motor, but if it all looks fine perhaps it was never ran in and is just tight or something .... or it has a thin layer of corrosion .... or they have the wrong piston in the sleeve ... hard to say with second hand stuff...

Heat and crank id say~

/edit
What size motor is it anyway .... the more details the better .. got any pics?
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Old 11-16-2010, 08:40 AM   #3
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It's an "Acme" 15 engine. I don't have a heatgun, a brazing torch should do it. It's almost midnight here, so I don't feel like it at the moment, but I'll maybe get some pics up.
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Old 11-16-2010, 08:59 AM   #4
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Quote:
Originally Posted by Mind_Reader7 View Post
I bought a bunch of nitro car parts from eBay, nothing great. There was enough pieces for 1 complete car and a bunch of spares. I'll sell it locally for a bit of profit. Anyhow, there was a spare engine, and the piston gets stuck about 3/4 of the way up. If the engine is assembled, I can force the piston to go around, however when the head is off, it just pushes the sleeve out, and I can't hold it in with my hand.

The piston and sleeve look fine to me, everything seems fine, without the sleeve, the piston is fine on the crankshaft. They're "Condor" buggies or something, pretty damn old, I believe they were made by HSP before they were even called HSP. Is there something I should try before condeming this engine?
use some nitro clean for the engine then put after run oil after that heat the engine with a hair dryer then fire that sucker up! then and only then you will know if the engine is any good. GOOD LUCK!!!!!!!!!!!!
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Old 11-16-2010, 11:04 AM   #5
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Tight is good. It means it's not even fully broken in yet.
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Old 11-16-2010, 02:24 PM   #6
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Tight is good. It means it's not even fully broken in yet.
That is what I was thinking!!!!!!!!!!!!
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Old 11-16-2010, 02:33 PM   #7
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Just as long as the carb is clean, and you have ballpark needle settings you should be fine. I would disassemble the engine, clean it, and then reassemble with lube. Heat the engine up and fire that thing up if you didn't find anything strange in the tear down. Sounds like a new / repinched sleeve + piston. Just make sure the bearings are good and don't have corrosion. If they do replace them. Good luck
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Old 11-16-2010, 05:04 PM   #8
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Quote:
Originally Posted by wingracer View Post
Tight is good. It means it's not even fully broken in yet.
+1
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Old 11-16-2010, 07:00 PM   #9
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It's not tight in the whole sleeve though. For about 3/4 of a revolution it's fine, in the last 1/4 it's pretty stiff, regardless of wether or not the head is on (giving compresison). I'll try running it soon, not sure if the pullstart will even pull it (the engien was disassembled when I got it).
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Old 11-16-2010, 07:05 PM   #10
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it is normal for them to be tighter at top dead center. the sleeve is tapered towards the top.

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Old 11-16-2010, 07:18 PM   #11
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yah its called pinch..

A mates new RB motor has crazy pinch, it wont wind over unless it's heated up and even then it will get a piston lock if the temp drops a bit.
Nearly impossible to wind over by hand.

Clean, lube and crank ... DO IT!

Have a look at the break in bible at the top of this forum section.

Last edited by NitoriousRC; 11-16-2010 at 08:45 PM.
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Old 11-16-2010, 07:42 PM   #12
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they might have over pinched the sleeve
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Old 11-16-2010, 10:07 PM   #13
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While I haven't got around to playing with that engine yet, I was playing with the one that was already in the car. It has good compression, and looked intact. After 20 mins of trying to start the, I was seriously mad. I took the engine out, and took the carby off, cleaned it to death, then took the exhaust off to clean it, that's when I noticed.....
Whoever had this nitro car before me, put the sleeve in completely wrong.

God knowns how he managed to mess it up, there's an indication on the sleeve showing where it goes. Once I had taken the exhaust off, I looked into the outlet, and only about 2mm of the 15mm gap was open. The engine runs nice now. Not the greatest in the world, but has great acceleration.

The only bad things I can say about this car is, there's no clutch, so you can't really idle, and everything is screwed to the top plate, and the top plate has 4 screws into each gearbox, and 2 into the base plate. Seems decent otherwise (besides poor quality parts).

Last edited by Marcos.J; 11-17-2010 at 06:16 AM. Reason: no profanity
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