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air leak or what??????????

air leak or what??????????

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Old 11-17-2009, 06:58 PM
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Questions?? air leak or what??????????

I've bough a Picco P3 ,28 used. Try it today, and when i let it idle, the engine start to climb realy high in RPM's. I have richen the LSN, but not change anything, and when i say richen, OMG the needle was near to fall of the barell

I've remove the flywheel, put a fuel tubing on the carb, plug the exhaust and carb intake, and blow by the fuel tubing, and i could ear some air. So i've put soapy water on the front bearing, and lot of bubles cames between the crank and the bearing, but not by the bearing seal

I this air can make this engine to not idle at all and make it so hard to tune????
And what can i do to solve this airleak??

I know that a bearing who leak by the seal is easy to fix, only chage the bearing, but when the bearing leak by the gap between the crank and the bearing, for me it's the crank OD that are to small and not seal good

I've try my JPX 28 carb, and same thing, so the carb is not the problem i'am sure.

I realy start to think that this Picco are dump.
The guys who sell me the engine told me that this mills has only 1.5 gallons included break-in.

Don't know why this guys not seen this problem before, or it's why he sold it...
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Old 11-17-2009, 07:04 PM
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Did you try and pull the crank tight when you did that? With the flywheel off the crank will sometimes push back a little and give you a false leak. When the flywheel is on it pulls the flywheel tight and seals.
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Old 11-17-2009, 07:04 PM
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im having the same problem now with my nova .21 bf all the sudden thats why now i know to seal the engine when its new , i nocited my carb has a leak it has fuel all a round it and my carb bolt got loose and its strip so that doesnt help i tryed to tune the high and low end needles and they wouldnt do anything and the same probem with the idle that u are having it goes from slow than fast with the wheels rolling and adjuting does nothing so i know theres a leak for sure ,u proberty have a leak around the carb my guess
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Old 11-17-2009, 07:06 PM
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can u turn the flywheel with your hand all the way and hear the piston pop
cause my does that and my is pretty new so i know its a leak
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Old 11-17-2009, 08:08 PM
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Originally Posted by tc5 man View Post
can u turn the flywheel with your hand all the way and hear the piston pop
cause my does that and my is pretty new so i know its a leak
Yes i can turn it by hand, and i hear the piston pip, but why this could be an air leak??? I don't understand the piston pip and air leak

And for the rest of the engine, it is seal all the way, around the carb, backplate and were the metal to plastic meat on the carb.
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Old 11-17-2009, 08:33 PM
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i dont know then but my for some reason lose its tight compession i mean u could not turn it with your hand and its still pretty new ,i think if u have a leak around the carb u loose some of your compesssion not sure though
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