Pinning the combustion chamber was one of the best things I ever did for the
Tr engine. I came up with that after a close inspection as has been
described by others here and figured it out on the airplane ride home form
Portland ( and another blown head gasket) . Fixed the deal and it's so
simple. You do have to be careful if you skim or mill the head again after
installing the pins cause the hardened pins will eat up a mill end in a
hurry. Surface grinding works fine though. Oh yeah, I did work out the deal
for Carl Swanson and several other people also. Can the mid 60's be that
long ago??? Wow I must be older than dirt.
----- Original Message -----
From: "Greg Solow" <gregmogdoc@surfnetusa.com>
To: "Brad Eells" <bradlnss@lightspeed.net>; "MARY HODGSON &"
<STLNYC@email.msn.com>; <fot@autox.team.net>
Sent: Sunday, February 17, 2002 10:56 AM
Subject: Re: Cylinder head thickness and the PHA
> What Jack Drews posted looks about right. I would post a photo but don't
> have a digital camera yet. The pins I have used are 10/24 machine screws
and
> the end of the screws sit against the outside bottom wall of the exhaust
> port. The first head I saw reinforced this was was off of Carl Swanson's
> Morgan. I bought the head from him in 1966. I think that the pining was
> actually done by Kas, or at least in the Comp dept shop. The weakest are
is
> that next to the triangular water hole at the rear of the head. I t is
> possible to look into the water jacket and see that the casting tapers
> gradually thicker as it goes farthur from the actual water paasage hole,
but
> is still quite thin and bridges a wide area with no internal support as
you
> follow the line of contact with the cylinder liner. The pressure of the
> cylinder liner, .003" to .006" proud of the block, and the heat and
> vibration stress while the engine is running tend to cause the head
surface
> in this area to warp up and away from the liner if this area gets to thin.
> The pins spread the load to the exhaust port bottom floor and prevent this
> "collapse."
> There are normall 3 pins in this area, about 3/8 " apart. These are
> dupicated in each of the cyinders. Then the is 1 pin in the "mirror image"
> location of liner contact, still on the manifold side of the head. The
head
> is plenty strong on the spark plug side. The only problem over there is
the
> "creep " of the spark plug cooling water passageway toward the combustion
> tchamber and head gasket sealing area as the head is milled more and more.
>
Regards,
>
> Greg Solow
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