engine oil in primary, again!

[dieselguy65]

so, three seals in a month. Got the bike and noticed right off engine using oil, not leaking. pull a lower screw out of the derby cover and oil comes out. figure somehow they overfilled it, not sure how. drain and refill to correct level. a ride to College Station Texas and back, few hundred miles, engine oil down again, oil comes out lower derby cover screw. pull primary, chain, clutch, etc. engine crank seal looks fine, is installed correct and to right depth. get new seal, put in. ride 300 miles, and guess what, primary full of engine oil again! this time to the point it comes out the hole for the charging circuit!
so, tear down, get another seal, and pull the sleeve the seal rides on, small bit of sealer under that sleeve. Install seal, backwards this time according to book. but to me makes sense with the lip side towards the engine oil pressure. another few hundred miles, engine oil down again, no leak. primary slowly filling up.
now I been turning wrenches 25 some odd years, worked on everything there is. Got not much experience on these Evo engines. but I know how to put a seal in. and I have went thru the factory manual, just cant find another spot there that engine oil could be coming thru. this is by the serial numbers an 01 80 inch Evo. the engine is not the one for the frame, frame was replaced. anybody have any idea how the engine oil gets in the primary? I checked case when apart, no visible cracks, or other places of seepage. and the amount that gets in there in a short time tells me its got to be pressurized oil getting in there, not just oil sloshing around.
thanks,
Brian

 

[BUBBIE]

Is there room to put a double seal,,,, Back to Back ?

This is all I have,,,, OR a crack leaking under pressure..??

signed....BUBBIE

 

[HDDon]

Did you check the crank shaft runout?

 

[dieselguy65]

I cleaned the area with carb cleaner, let sit overnight. no visible cracks, no seepage. no room for double seal. crank endplay and runout was checked with dial indicator, someplace i have it written down. prolly tear it down again, its driving me crazy cant go more than few hundred miles and the level is noticably increased. am i right that there is no other place inside the primary that engine oil could be getting into it from? or am i overlooking the obvious?
there is one other thing, the two vent on top of the rockers are just open, no place to run them into the aircleaner I have at the time. and I have always hated that, seems to soak the airfilter and when you stop oil drips onto exhaust. i do not get any oil film out of them, no blowby that is noticeable at all.
thanks,
Brian

 

[2000classic]

My first thought is your crankcase may not be venting properly. Becoming pressurized and forcing oil past the seal.

 

[BUBBIE]

My first thought is your crankcase may not be venting properly. Becoming pressurized and forcing oil past the seal.

GOOD CALL.... 2000classic

If the gaskets were not in the right direction, covering the vent oil holes, it would Not vent properly and Build up of pressure That Could pressure oil to flow out and into the primary..

signed....BUBBIE

 

[Breeze3at]

A noticeable amount of oil in the primary after just 300 miles is oil being FORCED into the primary. Like 2000classic said, something is not right with your head breather vent system. There should not be enough pressure in the crankcase to blow oil past 2 new seals. You should be able to feel some pressure coming out of the vent hoses, even at idle. Is it possible that somehow, solid bolts got put into the head breather holes instead of hollow bolts?
P.S. In original post you stated "01 Evo". I thought 2000 was last year of Evo (softails only)? Does not change diagnosis anyhow.

 

[fin_676]

Up to 92 the evo engine had the breather on the main crank case to the rear of the rear cylinder after that the breathers were in the heads if solid bolts were in the breather holes that would raise crank case pressure sufficiently to blow the oil past the seal

Brian

 

[BUBBIE]

Up to 92 the evo engine had the breather on the main crank case to the rear of the rear cylinder after that the breathers were in the heads if solid bolts were in the breather holes that would raise crank case pressure sufficiently to blow the oil past the seal

Brian

Memory again for me... If the oil return in the engine, under the cam area had a way of wearing out and Not in time ,,,,,needed to remove oil from the engine,,, Plastic and metal ones were used to replace the worn-out Cage type rotor... Timing with the Gears was very important.

If out of time they also caused EXCESSIVE back-pressure and oil out the seal.

Man the things I forgot about..

signed....BUBBIE

 

[dieselguy65]

thanks to all, things to check for sure. i will check for solid bolts in the upper crankcase vents. yes, it is an 01 Evo, 80 inch according to engine serial number, out of a softail.
thats the bike it came out of, and serial number confirms it.
gonna have to tear into nosecone if the bolts are ok, and see if some how the breather gear is mistimed.
little more investigating is in order, and quick. poker runs coming up fast.
thanks, Brian

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ok, little more investigative removal of parts. seems those breather banjo fittings in head are just spacers. there is a 5/16 allen head bolt goes thru them, which is solid and not hollow. and the hole they screw into does not appear to go anywhere.
one thing did notice while bike is idling, after 5 mins or so I can noticed a few very small drops of oil on ground right under where the breather line between engine and oil tank come out under bike. so maybe the problem is a mistimed breather? I am thinking now to tie a small bottle under that hose, and ride and see how much oil collects in it after say 50 or 100 miles.