coolant where it shouldn't be

I

Ian C

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Anybody seen this before? The engine is a 1982 M90, 1980 M90 head which has had a full refresh, not been run since and coolant is leaking into the areas in front of cam bearings 2 and 3 and down from there. My first thought was the plug in the centre of the head not sealing, but that doesn't explain the coolant at cam bearing 2. The car is raised on stands at the front so a bit of an angle backwards, but I can't see it getting from bearing 2 to bearing 3. When I first saw it I cleaned it away and watched it slowly appear again and the 2 pools grew at the same time. I guess instead of starting it in the next few days, Ill be lifting the head to deal with this, but I am puzzled. Ive had cracks in the usual places before, but this is new to me. IMG_0724.jpegIMG_0725.jpegIMG_0726.jpeg
 
I would guess it’s head gasket. Water is going into oil galleys up the head bolts.
 
That makes sense Don. It has been cranked a bit for trigger offset calculation, and there was coolant in other similar spots so maybe coming through the rocker shafts under pressure and dribbling out of the cam bearings down low without pressure. I guess I can check by pulling the bolts near the pooling. This is the longest engine swap in history, the head has been on for quite a while but not run up to temp and angle torqued. I don't know whether that could be part of it, perhaps I damaged it while fitting the head.
 
Hook up coolant pressure device - pump to 15psi and you will see water coming out of rockershaft bores from headbolts. M90 headgaskets ONLY from BMW !!
Call Carl Nelson for more info. I have a stack of bad m90 gaskets bought from other providers.
 
I'll be ordering a gasket today... from BMW. The one on the engine is from a German after market manufacturer.
 
If you micrometer the difference between composition material and the fire ring you will see the problem- that ring really needs to be heated and crushed to keep the water from migrating.
 
I'm an hour into getting the head off, and got a HG coming from Germany, about the same price Bert mentioned. I appreciate your help Don, I would have gone in circles for a while without it.
 
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