Oil Leak from cylinder head - help !!

maurice crocket · 05-13-2004, 07:43 AM

I have a 1998 R1100S that i bought as damaged repairable, - i have repaired the bike (in boxer-cup colour scheme) - all went fine, but it has developed an oil leak from the right hand cylinder head.

I am sure the bike "when down the road" on this head and assumed it would just be a case of replacing the base gasket on that head, but on speaking to my local BMW dealer he tells me that there is not a gasket fitted ? - apparently there are four dowls that the head fits into.

I am wondering if anyone has come across the problem of an oil leak from the bottom of a cylinder head & if so how did they cure it ?

badger · 05-13-2004, 07:49 AM

R U sure it's the head to block seam that's leaking? Could it be the valve cover to head seam that's leaking? It has a gasket that can leak.

roger albert · 05-13-2004, 10:14 AM

Yes, we need to get the terminology straight.
Is the leak between the crankcase and cylinder, or the cylinder and head, or the head and valvecover?

I don't honestly know what's right on the oilhead.
If it is correct that there is no base gasket (that's the one between the cylinder and crankcase on some motors) then there still ought to be an oring. Since the camchain tunnel is here too, I think there would have to be something sealing it all. Can't just be a plain round o-ring

Please be more specific where the leak is and maybe we can lend a hand.

BMW Atlanta · 05-13-2004, 10:18 AM

well there are two mating surfaces oil could be leaking from. The cylinder head to jug has a metal head gasket that is replaceable. The other surface is the base of the cylinder jug and this does not have a gasket but is sealed with a special base cylinder sealant. I have seen both surfaces need attention, usually its one of the other. Determing where your oil leak is and that will tell you whether you will be just replacing the head gasket or removing the whole jug and resealing the bottom to block and it would be adviseable to replace the head gasket too on that age bike since youll be right there.

Good Luck

AndrewA · 05-13-2004, 11:03 AM

I bought a wrecked bike the went down slid down the road on the right cyl.

I had an oil leak too !

Have you checked the inner gasket that goes around the spark plug ?

If that gasket is deformed in any way, you can get oil to blow out of the bottom of the motor, all over your boots as well as the rest of the bike.

Simply remove the valve cover - there is a second gasket that goes where the spark plug enters the head. Be really careful when reinstalling not to redeform.

maurice crocket · 05-14-2004, 02:19 AM

Thank for your replys - i think after reading them that i will take the head off & see where the leak is specifically - if it is from base of Cylinder i will use sealent as suggested by BMW Atlanta - thanks

craigtvw · 05-15-2004, 02:40 AM

I had both gaskets leak on my R1100RS, the replacement is pretty simple and I used a dealer after fit version which was multi layers of metal. The originals were paper. The replacement is not too difficult, just keep an eye on the cam sprocket and leave it in the chain when the head comes off.
Forget the sealant solution, replace the gasket and ll will be fine, probably.