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problems with motor "seizing".... ideas?

problems with motor "seizing".... ideas?


Old 09-05-2008, 12:01 AM
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Default problems with motor "seizing".... ideas?

I just got this kyosho 1:10 nitro touring car on ebay. Found out I may have overpaid a little but I'm rolling with it. So i get everything set up and I have a sirio evo3 .12 motor that I got off the guy which he said has had about 3/4 gallons through it. Now i can't get the motor to turn over to save my life. The problem I'm seeing is that the flywheel (it uses a start box) gets stuck from the piston "seizing" every time I try to start it. I can wiggle the flywheel free and hear the piston compressing out of the exhaust when I flip it with my hand, and it will turn over for a few seconds on the box but then it will seize again. I actually had it running for a few seconds but then it locked up again. I can tell it is the actual piston being stuck and not the clutch or the gears because everything else still moves free. I literally had to give up trying today because my fingers got all blistered up from freeing the flywheel repeatedly. I can tell that the motor is getting fuel, I took the carb off and cleaned it out, replaced the fuel lines, replaced the plug... but it all seems in vain because the flywheel repeatedly gets stuck. Any ideas? Each time it seizes i am unable to turn the flywheel in a full rotation in either direction without it hitting a stop and eventually just sticking. The guy insists that he used after run each time he used it and that it never sat dirty for any length of time. I am pretty frustrated at this point and any help or advice would be greatly appreciated!
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Old 09-05-2008, 12:09 AM
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Make sure your starter battery is fully charged to get the flywheel to turn over. Then remove the glow plug and add a few drops of after run oil in the engine. Now try turning the engine on the starter. It should turn w/o problem. After its been "oiled up" put the glow plug back and tighten it.
Try starting the engine again. If it continues to seize at tdc, heat up the engine with a heat gun or blow dryer, then try starting it again.
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Old 09-05-2008, 01:11 AM
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ahhh the after oil is the secret eh? I was wondering if the gas would be enough to free the piston by itself and apparently it's not. I'll have to run grab some of that tomorrow and see what happens. Thanks!
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Old 09-05-2008, 02:05 AM
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It just sounds like your piston is getting stuck at TDC. This is a good thing as you still have heaps of compression left.

Dnitro pretty much summed up what you need to do. Or you could even try starting it with the plug a little bit loose then once started just nip it up

Try that and see how you go. Keep us updated on your progress.
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Old 09-05-2008, 04:02 AM
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Heat up the engine with a hairdryer.
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Old 09-05-2008, 06:36 AM
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heat gun/ hair dryer is the ticket...
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Old 09-05-2008, 07:40 AM
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sounds like the motor isnt compltetly broken in definiytely pre heat motor add the after run recommrnd changing to hotter plug richen bottom end 1 hour to keep more fuel in the motor .what plug in the motor. the experiance with that motor is for it to like to run lean . my way around it was to run the hottest plug i could find os 3 it keep the bottom end clear out and allows you to run richer on the bottom end
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