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Green oil on crankshaft

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Hello everyone ! 
Today, I got my new top end for my 90' 125 rm. While removing the cylinder, i grabbed the connecting rod and rotated the crankshaft few times. I was then surprised to see strange oil on it. Green, high viscosity, smells like motor oil. My water in the cooling system is green, so maybe some drops fell in the crankcase while pulling of the cylinder, mixing with remains of mix ? Here's a picture of it :
The green stains, perfectly aligned when the crank rotates, are visible on each side of the cylinder. The bike was running fine before that. Anyone have an idea? Is this normal? Thank you to enlighten me before i put my new piston ! :)
 

IMG_0034.JPG

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When you took your cylinder off coolent must've gotten in crank case and when you spin it collects on the halfs. Either take engine off or tip bike upside down.  That's my geuss anyway 

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Did you measure the trans oil and the coolant level after draining? If you are confident your seals are good. Dump diesel in the crank, rotate the crank around and flip the bike upside down.

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Did you measure the trans oil and the coolant level after draining? If you are confident your seals are good. Dump diesel in the crank, rotate the crank around and flip the bike upside down.


^ this. Definitely looks like coolant to me. If seals aren't bad, flushing the cases should hopefully do it. otherwise you might have to split the bottom end, clean things up, and replace the seals.

If you go the longer route, you may as well do a full job while you're in there if it's been a while since it's been done.

Good luck!

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I think my seals are OK for the moment, so i wont take the pain to split the case ! I've flushed the bike, flipped it (two times) and no more green deposit ! i'm hoping to finish the top end this week, so if i blow up this weekend, i'll let you know. I'll take the full job for the next rebuild. Thanks for the help to everybody !

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