Is the head gasket supposed to hold back oil ??

[thessler]

Hi
Sorry to keep asking questions, but I seem to be stumped again.
Yesterday I fired the bike up for the first time. This is the bike I recently got with a large whole in the piston due to an exhost valve trying to escape.

I have a pretty bad oil leak between the head and the cylinder, like a continuous drip.
Removed head, the head gasket was dripping with oil from the top long studs down to the bottom.

I am trying to figure out how these rocker arms get oiled, it seems somehow the oil should come up through the push rod tube and drain back down through same tube. But I am really not clear on this.
If I am close to correct the oil has no business up around the top mounting studs. Which leads me to believe the head gasket isn't really there to hold back oil, just compression.
There are two O rings on the top mounting studs at the base of the cylinder, not sure what they do but I don't think oil should be coming from up there.
 Any insight to how this works greatly appreciated.
I will buy a new head gasket, but I'm just trying to eliminate any other causes. Not sure a new gasket will change anything.

    Thank You, Tom

[Bob_Roller]

The rocker arms get oil from around the long hold down studs I believe it's the lower studs on each cylinder, the head gasket has to seal oil pressure, so a bit of head sealant wouldn't be a bad idea either in the area around the studs and pushrod openings .

Also, I believe it makes a difference how the rocker arm shafts are installed, they have oil passageways to get oil into the rocker arm bearings .

Haven't had any off in a while, so I can't tell you how they are supposed to go on .

[Mike V]

Tom,

Yes, as Bob stated the head gasket does seal oil and compressed air/fuel. The rocker assemblies get oil delivered to them by way of the upper head studs.  At the base of the upper 2 studs is a small delivery port where oil is pushed under pressure and is sent along the studs to the upper portion of the rocker tower and down the arms where is is flung about.  Basically.  Then oil is returned to the sump by way of the pushrod tubes.  Look closely at the attached pictures, the oil delivery port is visible at the base of the stud, on the next photo you can see the oil being delivered from the upper portion of the rocker arm.

Here's a link to Bum's site that is quite detailed and lengthy regarding the oil system and every other inch of our bikes in more detail (& accuracy) than I could ever muster,

http://bmwmotorcycletech.info/oilsketch.htm

[thessler]

Ok thanks
I'll order a new gasket in the morning. It was leaking so bad, almost like a free flow I thought maybe I had a different issue.
 Thanks, Tom

[Air4Life]

Is it possible to put those gaskets on incorrectly, where it would lead to this kind of issue?

[tvrla]

If that's a new gasket, it shouldn't be leaking like that. I've re-used gaskets and never had them leak - though I now put a very thin layer of sealant ringing the top pushrod holes, on both sides of the gasket these days. Go ahead and re-use your gasket, I believe your problem is somewhere else. Check for gouges in the metal, or a warped head.

Is this the side that got replaced? You replaced both heads, didn't you?

[Mike V]

Check for gouges in the metal, or a warped head.  

Curious if you've performed a compression test or leak-down test?

[thessler]

Hi
No leak down or compression test yet just got it running and leaking.

Wirespokes- yes this side got the new head and new jug. The other side got new head and does not leak.
My thoughts exactly " I think there is something else wrong ".
Gasket is in good condition, metal surfaces are perfect, gasket was put on correctly not backwards.
This is not a little leak where it can be ignored while I work on the rest of the bike.
    Thanks, Tom

[Barry]

Bear in mind that the method of oil delivery to the rockers already described relies as Bob mentioned on the rocker shaft being correctly oriented otherwise there will be no oil flow and has a result higher oil pressure at the gasket joint. This won't help though still shouldn't have leaked.