Trouble shooting oil coming out top end CRANK CASE PRESSURE
To much oil in engine case, causing crank case pressure. Like a balloon building pressure until it escape’s. Oil will blow out at the weakest point.
Recently change oil, possibly over filled oil tank.
Take in consideration when changing oil. You will have approx ¼ cup
Of oil left in bottom of engine case. Know what size oil tank you have before you start filling your tank with oil.Stock soft tail is 3-1/4 qt oil. Oil filters are like sponges they will absorb approx ¼ cup of oil. Don’t over fill because the oil level looks low.
Oil filter blocked or if Blowing oil filters off
Hand turning oil filter, must turn 1/4 by hand, then use oil filter wrench made by Harley turn an additional 3/4 turn.
When hand tightening oil filter, not using a wrench, if not tight enough oil filter WILL BLOW OFF from pressure.
Oil filter mount or oil cooler lines crossed or hooked up backwards.
Wrong oil filter will cause major blow by. No after markets used here.
THIS IS FOR TP ENGINES
Classic oil filter part # 63796-77A EVO oil filter 40 micron
Smart oil filter can use either 5 micron, 10 micron or 40 micron
Part # 63798-99A (5) micron filters dust
Part # 63798-99 (10) micron filters small particles
Part# 63796-77A (40) micron
Restricting breather bolts, bolts too small. Vent holes for breathers should be (.187). Make sure when putting extension on breather bolt holes are not Covered, Defeats the purpose.
Oil returning in tank, vent and return are not covered in oil. This will suck oil back into engine not allowing it to breathe properly and willcause blow by, engine will get very hot.
Vent and Return lines inside tank, broken.
Poor return
Pinched hose
Collapsed line
Race track gaskets, torn, bubbled, or worn should be replaced.
Piston sealing problem, low miles engine not seated yet
Oil cooler too high and or lines routed incorrectly.
Rocker box lids are backwards. Front lid on Rear and the Rear on the Front.
Keep in mind if having blow by issue's even after changing all your gaskets or o-ring’s, unless rocker boxes cavity's, carb, etc are cleaned out with break cleaner you will have left over residue that will still blow out, eventually all blow by will be gone.