> I recently rebuilt my engine. I had the head shaved a little to
> increase compression and two seats replaced. When I got the head back
> the mating surface to the engine deck was kinda rough... like a file.
> You could see the cutting grouves. A friend told me that this was due
> to the fact that they used a course stone to cut the head since I was
> taking a bit offthe head. He assured me it was ok...
We had exactly the same thing on a customer's car about a year ago. I
didn't like the look of it at all but the machine shop swore it would be
OK. I just had to replace the head gasket on that guy's car last month.
The rough cut is not OK! take it back now before they 'forget' they told
you it would be OK and make them cut it sooth. You mention using a "comp"
gasket. Where did you get it and how much did you pay for it? There are
several "comp" look alikes out there and they are just junk! The real
"comp" gasket sells for more than $75, and that's just for the head gasket
itself, not for a complete head set. If you did not pay about that much it
is one of the imitation "comp" gaskets. Junk it!!! I have found that the
Payen brand gaskets are about the best for a street motor. I smear some
sealant (non-hardening type designed for head gaskets, Fel-pro sells one
to be used with their head saver kits, which are solid copper shims to be
used with a head gasket to save a skimmed OHC head) on both surfaces of
the gasket, on the distributor side where all the little steam holes are.
This seems to slow up the typical "seepage" you see on MGB's (nothing
seems to stop it) just around the number plate. You don't need much at
all, just a very light smear. I do not recommend using aluminum paint or
anything else on the gasket. And I never coat the whole gasket. I started
using special oversize nuts on the head studs about 3 years ago on all
engine I build. They spread the clamping load out better and seem to
help. The nut has its own built in flange and is much larger than the
stock nut, being about as big across the flats as the stock washer is.
Another thing I always have checked now is that the top of the head is
parallel with the bottom (after skimming). If not, or if the head nut
locations are damaged (fairly common now) I have the top of the skimmed
too. On MGA's I dump the aluminum rocker stands, and go to the MGB's iron
ones, or I insert the aluminum ones with steel sleeves.
Point being I just paid the price for buying that 'its OK' crap, IT
ISN'T! The head must be smooth.
Marc Sayer
Performance Engineering
1070 W. 2nd Ave.
Eugene OR 97402
(503) 484-0904 Fax 746-0863
msayer@efn.org
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