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Head job

dhunt

Freshman Member
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Restoring/preserving/wrenching a Bugeye with a 1098 upgrade. The car is not on the road but I drive it up and down the driveway once a year to make sure nothing is stuck. I decided to treat it to an oil change but very disturbed to see the oil come out the color and consistency of chocolate milk. As the coolant drained out uncontaminated I fear the head gasket needs replacing. There was no smoke out the tailpipe. My 2-part question:
a. Is there any other suspected cause other than the head gasket?
b. Both my spare new headgaskets have no indication which way up they go. One side is metallic, the other side black. Bentleys "official" guide for 948-1098 engines says that they are tagged "top" and "front"...they lied! Which side is UP?
Thanks for any help. ps when I drove my original Frogeye in the '60s in England I swear they were larger and faster!!!
Dave
 
Others will have to answer the "which side is up" question on the head gasket.

Yes, your engine could have a blown head gasket. This would be a good application for a leak-down test. It will help you find if there is a leak.
 
Regards the 60s: they were both bigger and faster back then. Blame continental drift. And the music was better too....
 
Obviously, when you pull the head it will be essential to check if for cracks (magnaflux - cheap and easy in a shop) and to make sure the blanking plugs are all level with the head. If it were me, I'd consider re-building the head; not that expensive.
 
We had a 1275 cc head rebuilt and 8 hardened seats put in (to cope with that there new-fangled unleaded gas plus all the valve seats were pretty well recessed) and it was $700-900 Canadian. Costs, of course, always depend on who's doing it, and what needs to be done - our head was in pretty poor condition. But get the good advice regards the condition of the head and the seats. I always figure that I should hum Procul Harum's 'Whiter Shade of Pale' ('her face, at first just ghostly, turned a white shade of pale') when getting estimates for repairs etc.
 
I'll second all that.
You can save a little money by removing the valves... but a good shop will make sure the head is crack-free, flat and put in the new guides. Taking in the head and bits, I'd guess $700 USD.
 
$700 sounds about right. If you buy a turnkey rebuilt 12G940 head from Seven that's what they charge. However, shipping a head is not cheap.
 
I always thought that the exhaust valve seats were all that really needed replaced. I'm betting that the problem is due to the recessed center plug though. That is if the 1098 had them.

Kurt.
 
In our case, the valves were all really badly recessed, and the machine shop basically salvaged the head by putting the inserts in for both intake and exhaust. Kurt - you're definitely correct in that normally it's only the exhaust valves that pound themselves into the cast iron; I have no idea why my head (so to speak) was in such poor condition.
 
I had the recessed blanking plug problem (and that plug crossed the fire rings of the gasket such that there was communication between cylinders #2 and #3). Doesn't take much recession to cause the problem (on my 1275 head). Total frustration until I pulled the head and there it was! Rebuilding the head was the way to go since it was generally worn. Interestingly, it had been done before because the seats had been replaced (so that saved some money).
 
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