pulling transmission oil into crank

[mookman]

hi there,
i hope someone can help me. i have friends blaster came to me siezed up.
got a piston and rebore, rebuilt it it sucked all the transmission oil through the seal, ok, new seal filled to correct level did it again. this time new seal and coller, found out breather was blocked, unblocked it , refilled to halfway up window, did the same thing again.. has anyone heard of this before . its like there is an engine breather timing fault, but as it doesnt have one ...
i will try again running it with the filler cap of and see if this helps reduce crank pressure .
has any one had a problem with after market pistons , maybe its creating to much crank pressure..
any help please , im starting to doubt my sanity.
cheers.
mookmanX(

 

[Mrbrocco]

did you replace all the seals?

 

[mookman]

hi, thanks for reply,
no only replaced transmission side, the bike was one of these (it worked fine until my friend siezed it up).
i looked a flywheel side and there was no sign of any mist( also no numbers on seal)
it looked as if it had been changed at some time as there were signs of silicon.
i have now bought a complete seal kit from england ( i live in spain, and parts are a nightmare here).
have you come across this, i used to work for italjet , and have fixed loads of chinese quads living here, buy this is a new one on me!!!

 

[Cochise]

Crank Seals.

Post is too short.

 

[wrench man]

Did you put in the OE double lip style seal?, or a single lip seal??

 

[mookman]

new seal looked good double lip with a compression spring on both sides.
i dont think flywheel seal is u/s as bike starts, idles, and revs ok....
well until it pulls oil through and bogs!!!!!

 

[chuck_neste]

Is there any cracks in the case?. I have one case that is cracked between the balancer/ bottom crank area that sucked in oil like crazy. The thing bogged down and sprayed smoke for mosquito control as well

 

[mookman]

got it stripped now, im going to put an air line adapter into the head and see if i can see or hear anything, please keep any answers coming as this is driving me mad.
re hand guns thread ivë got a cz75 in 9mm which i use for ipsc (practical) plus some old black powder guns... you yanks must have been fine shots, as i can just about hit a barndoor with a cap n ball colt!!!!

 

[FLOTEK]

did you do a leakdown test ? the left stator seal will suck air and lean out the right seal will suck tranny fluid

 

[mookman]

done a leakdown test, best as i can with tools at hand...
all seems ok , i will clean the bottom end ,rebuild (again) and try running it with the oil filler cap out at least this way i can find out if the oil is being sucked or blown in..
keep the help coming.
mookman,