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Yamahauler
05-25-2007, 11:12 PM
I havent been able to get my ytm200 to idle since I sunk it, filled the freshly rebuilt motor with water, and schreeched a bearing. :mad: :mad:

It does run very well still, little bit of smoke (probably fried the rings) and some piston slap.

I have scrubbed the carb completly clean twice, took the air box off and washed it all out, but once its running for about 1 minute, it wont idle.

I thought maybe there is some blow-by and its pressurizing the crankcase. I cleaned out all the passages for the crank breather, but still wont idle.

I tried taking the dip stick out while running it, and it seems to idles like that. So now im wondering will a new set of rings and a hone solve my blow by problem?

Before I rebuilt the motor, it used to smoke like crazy, but it would idle just fine. Its not making much sense right now, its not smoking as much now as it used to, but it idled before when it smoked really bad.

Anyone got some suggestions?

1upfront
05-25-2007, 11:34 PM
You are probably right . The rings are probably stuck in the ring grooves and allowing blow by to pressurize the crankcase. If the engine is fairly fresh you may be able to just remove the rings clean up the piston and rings rehone the cylinder and put it back together.

Yamahauler
05-25-2007, 11:57 PM
I was just thinking I am going to hone and throw a new set of rings in, since I already have a set here. Just got to buy a gasket kit.

I just have to find the time now.

BigRedRunner
05-26-2007, 12:54 AM
Have you bored the engine? Rings alone may not solve a thing. You need to measure up and down the bore checking for taper and also determine your piston clearnace.

Yamahauler
05-26-2007, 01:04 AM
Yes, I bored and put a new oversize piston in. I will still be checking clearances tho.

_brad_
05-28-2007, 01:44 AM
Isn't there supposed to be a little pressure in the crankcase? When I remove my dipstick while running I can feel and see oil being blown out of the hole...