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Oil In Engine

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I decided to do the top end and while installing the new piston I noticed that the crank was picking up oil from the bottem of the engine case. The crank actually had a film of oil that was running off it as I turned it.

I suspect that this is an indacation that the crank seal has failed. It just seems to me that a two stroke shouldn't have a pool of oil in the bottom of the engine.

Does the pool of oil warrant inspecting the crank seal? The bike has run "rich" and fouled a number of plugs. My jetting is 38/168 for the PJ/MJ.

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I decided to do the top end and while installing the new piston I noticed that the crank was picking up oil from the bottem of the engine case. The crank actually had a film of oil that was running off it as I turned it.

I suspect that this is an indacation that the crank seal has failed. It just seems to me that a two stroke shouldn't have a pool of oil in the bottom of the engine.

Does the pool of oil warrant inspecting the crank seal? The bike has run "rich" and fouled a number of plugs. My jetting is 38/168 for the PJ/MJ.

I'm not saying you don't have a leaky seal but oil in that area is normal. As your fuel mixture enters the cylinder some of the oil get's thrown off and puddles in the bottom of the crankcase. This loose oil is what lubricates the main bearings, seals, and cylinder walls. The oil that get's burned up just goes out the pipe as smoke not doing much other than to irritate the liberals. LOL

It sounds like from what you have said you are normal. You want enough residual oil in the case so that when the crank hits the bottom it can pick up the oil and throw it around inside the case to keep everything 2strokin'.

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John, as olddude said, your just fine.

Please try something larger than the 38 pilot jet. If you need a pilot that small in a yz 250, something else is wrong. How are your reeds looking?

That can cause a jetting nightmare.

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The reeds look fine; no chips, no cracks, appear to seal up with the cage, all four open and close. Could they be worn and not appear worn?

As far as the jetting goes I moved to my current set up one step at a time. The floats are adjusted correctly, new inlet valve.

I basically R&R'ed the piston and rings due to not knowing their condition and having the bike two years. The bike was fouling plugs regularly, has since I bought it. I really only trail ride and run a BR7 plug. Additionally the compression was about 150 lbs.

Would it be worth it to replace the carb slide with a leaner one? The slide is the stock one.

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I'm not saying you don't have a leaky seal but oil in that area is normal. As your fuel mixture enters the cylinder some of the oil get's thrown off and puddles in the bottom of the crankcase. This loose oil is what lubricates the main bearings, seals, and cylinder walls. The oil that get's burned up just goes out the pipe as smoke not doing much other than to irritate the liberals. LOL

It sounds like from what you have said you are normal. You want enough residual oil in the case so that when the crank hits the bottom it can pick up the oil and throw it around inside the case to keep everything 2strokin'.

Pissing off the liberals?? You nailed it.

Environmental crusaders aka liberals. I used to think I was a liberal some years ago (BTW G.W. still sucks A**). Then, I met the crusaders. Absolutely nuts they are. One argument I make with them is to reduce their environmental impact, why don't they just commit suicide? If population is the problem, why don't they just die for the cause?

It hit me hardest when the crusaders gained momentum here in WA state on the left coast. They nearly pushed a house bill forward that would restrict noise from dirt bikes and ATVs to NO MORE THAN 45 dBA in or near residential areas. My farts are louder than this!

This caused me to sell my four stroke bikes and buy THREE two stroke 250 MXers. My YZ is by far my favorite.

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