I need some help I have a cr250

[codyta94]

Hi im new here. I have a 2001 cr 250. I had to put a new piston in it but when I had the jug off I rotated the crank by hand and noticed it was full of automatic transmission fluid. I use atf in my crank case but is it normal for the crank to be submerged in this. Or is my gaskets bad? Please help

[factoryX]

Say what? Tranny fluid(ATF) sucking into the crank is a sign of blown main seals. 2 stroke cranks are completely sealed off from the tranny.

[codyta94]

Okay thanks I will still take  more opinions because I have heard mixed things abbout it

[cnrcpla]

If there is any kind of transmission fluid in the bottom end of the engine, your main crank seals are blown. They are pretty easy to fix, so don't worry to much about it. Welcome to the forum, we'll be here to walk you through any issues you get 

[factoryX]

What opinion? If there is pool of atf under the crank, then you have blown main seals. Where else is it coming from? Another thing you need to make sure is that it isn't premix as it pools at the bottom of the crank after 2 stroke motors cool down. 

[codyta94]

Is this easy to fix do I have to tear the entire motor apart?

[cnrcpla]

Double check what factoryx said, if it is in fact just 2t oil than your in good shape. If it is the seals, than you need to take the right side (Sitting on the bike) crank cover off, and take off the gear that runs off the crank. You will see the seal around the crank shaft and should be able to pop it out. To put the new one in, take a socket that fits the seal well and pop it in. Sometimes these things just slip out of place and can be placed back in, but you wont know until you get the cover off.

[codyta94]

So do I need to split the main case or just take the cover witht he water pump off

[TotalNZ]

How much oil are we talking about here? Sounds to me like it's just the pool of 2t oil thats supposed to be there.

[cnrcpla]

How much oil are we talking about here? Sounds to me like it's just the pool of 2t oil thats supposed to be there.

When he said full of trans fluid, I assumed it was way more than normal. In another thread he also said the crank was submerged. Pics would be helpful if you can.

So do I need to split the main case or just take the cover witht he water pump off

No need to split cases. Just take the water pump side cover off and you should be able to access the trans side one from there.