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1985 YZ 250 crankcase gasket questions

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hi everyone,

my bro has a 1985 yz250, and on the right side crank case cover by the rear brake, it is leaking. it is on the top portion of the case, and is leaking at the seal. oil will start leaking when the bike is running.

Can anyone recommend what i should do? how hard is it to take this case off?

also should i try and find a new gasket or just use the hi temp - make a gasket to seal this beast up?

Also what is the torque rating for putting the bolts back on?

and if anyone knows what size bolts hold these on?

would anyone use pb blaster to help loosen those bolts?

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its actually the ypvs housing gasket im looking for. i took off the 3-4 screws holding this on, and took the ypvs rubber seal off, this was the culprit.

i went and bought some hi temp make a gasket and just caked the whole thing up. hopefully this will hold for a trip until i get a new gasket and seal.

it appeared that the rubber seal was just letting oil bubble out while riding, but not just idling.

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Remove the power valve cover and see if the thrust plate is broken. This crescent shaped piece breaks frequently allowing oil to slip past the right side holder. A broken thrust plate also causes further vibration that stresses the screw holding both sides of the power valve.

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