oil in air box

[wilenduro]

I had a crank failure in my 04, put in new honda crank, bearings ,seal's ,gaskets, new piston, intake valves, replated cylinder ,new rings. Start it up it runs great. 5 min later it pushes oil into the air box. any ideas?

[fultz416ex]

crank seal is bad

[wilenduro]

The crank seals are new with a new crank

[hondarules]

i have the same problem my crank seal is bad an its blowin it in my air box but thats not the bad part..my filter is right up against the breather an it has blown oil in my carb an its all screwed up right now itll barley run

[hendershot106]

i have the same problem-- sparks says to never ever ever run the breather in the stock location--- pull it out cover up the hole and run it down underneath the carb and zip tie it to the frame above the chain------ and the oil comin out is only one of two things---- A CRANK SEAL or A CRANKCASE LEAK causing extra oil switching from side to side to blow out the breather--- THAT IS IT!

[hendershot106]

i have the same problem-- sparks says to never ever ever run the breather in the stock location--- pull it out cover up the hole and run it down underneath the carb and zip tie it to the frame above the chain------ and the oil comin out is only one of two things---- A CRANK SEAL or A CRANKCASE LEAK causing extra oil switching from side to side to blow out the breather--- THAT IS IT!

[hawk-trx]

could also be something as simple as overfilling the oil.

bad ring sealing can cause excess blowby and build crankcase pressure causing oil to exit the breather. (this happened to me)

is the tranny oil going down at the same rate as the oil leak? if so then i would blame the seals or a cracked case allowing tranny oil to overfill the engine side.

[wilenduro]

Ok I split the case's again, I don't see any thing wrong! seal's are brand new, case's are gouged up from the original crank failure, but I don't see any crack's. I do have ? though ,on the clutch side the balance shaft drive gear,(the first one on the crank) Does not seem to contact the seal when I look at it. Any idea's?

[wilenduro]

Ok guy's I figured it out with the help of my honda dealer parts guy. Rob at Fairway Honda in Somer's point NJ. Any way if you buy a replacment crank from honda make sure you get the right seal. there is a serial # split for 2 different seal's up to 8043347 use's the smaller inside diameter 30x44x7 seal, 8043348 and up use the larger inside diameter seal 34x44x7. Make sure you have the right seal or you will be buying a second gasket set, and spending another night in the garage, well maybe another night in the garage is not a bad thing. These seal's are on the right side (clutch) of the crank