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Discussion Starter #1
Trying to figure out where to start...compression good at 90psi...plug a little oily...trying to leakdown but wondering if decompression valve is affecting my reading similar to compression test...is there a way to shut it to do a leakdown? She blows blue when throttling up, but idle is pretty clear...any help troubleshooting prior to tearing it down would be great. Thx.
 

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Welcome to the board!:med:
 

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Discussion Starter #3
Leakdown was good...compression good...plug still shows carbon...doesnt want to idle by itself but just a touch of throttle keeps it ru ning however idle adjustment screw doesnt seem to help...where is this thing getting the oil from to burn?? you get a puff of smoke when hitting throttle...using a qrt oil every couple of hours...is there a gasket inside that could have let loose? Cwnt believe valve seals would equal losing so much oil
 

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Valves could be out of adjustment, seats could be worn, piston rings could be worn enough to let oil by and still have good compression. First thing I'd check is valve lash and valve seats and guides.
 

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Discussion Starter #5
Tore it down...piston and rings look very good...putting in new valve seals and guides...leakdown test showed minimal leakage, so im thinking valves and seats are good...I guess we will put new rings while we are in there...is there any cylinder prep required for the new rings like getting a ball hone and crosshatching similar to prepping a car motor?
 

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Yes, you need to hone the cylinder with a bar hone, not a ball hone. They are not strong enough for the nicasil coating in there to put the crosshatch back in it.
 

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Discussion Starter #7
THX...Can do on the bar hone...finally got parts in today...will post results after install
 
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