A tale of woe and frustration and TR6 heads...
If you know something about TR6 heads and don't feel like reading
the blow-by-blow, please skip to the end for the burning question...
Last Saturday I decided that now that my garage is pretty much
complete and usable after nearly a year of construction (yeah!),
it was time to pull the head off the dead TR6 that I've been
ignoring for months. It died one day and a compression test
revealed 155-85-0-0-70-155 :-(. Since my garage was only half-built
I decided not to deal with the TR6 at the time. I crossed my
fingers that it was just the head gasket (well, I can hope, right?).
Saturday: Spend most of the day trying to figure out how to get the
bonnet open without the aid of the release cable, which didn't budge
at all. The answer ended up being to pull the glove box and reach a
screwdriver through the wiring holes in the wall. I didn't figure
that out until I had the entire dash and all the instruments out :-(.
Sunday: pull off the carbs, manifolds, etc. and try to pull off the
head. It won't move. Use all the tricks described in the Haynes
manual. It won't move. Swear at it and beat on it with a 2x4.
It won't move. Four hours later, 4 of us (thank god for brothers :-) )
had it off. The exhaust valves on 3 and 4 both have holes in them,
so I pack the head in the Valiant for a trip to the machine shop.
Monday: Take the head to the machine shop and cross my fingers.
Tuesday: No call from the shop, that must mean things are fine, right?
Wednesday: Machine shop calls. The head is cracked and welding looks
iffy at best. Luckily we have a huge local repository of dead TR6's
available here in Seattle. Aurora Auto Wrecking, acres o' dead MG's
and Triumphs. I pick up my broken head on my way to the yard to make
sure I get an exact match. $150 plus core deposit and I'm heading
back to the shop with my broken head and the used one from the yard.
At least they now have double the valves and springs to choose from
when putting the new one back together.
Thursday: No call from the shop, that must mean things are fine, right?
Friday: Machine shop calls. The head from Aurora is cracked. Aurora
says to bring it back and swap it for another until we find one that
isn't cracked. Too bad my bill at the machine shop is racking up $28
a pop for cleaning and magnafluxing :-(. I can't do the swap today,
though, I have to drive my wife 30 miles to pick up the car she just
bought :-). A beautifully restored '65 Dart GT convertible. It ain't
British, but it's pretty dang cool. Stock as a rock, looks like it
just rolled off the dealer's lot in '65, right down to the Mopar battery.
Saturday and Sunday: mountain bike riding in Canada. Can't work on
the TR6 anyway, right?
Monday: Pick up head number 2 from the machine shop and bring it back
to Aurora. Get another head and take it to the shop. Cross my fingers.
Tuesday: No call from the shop, that must mean things are fine, right?
Wednesday (today): Getting itchy, I call the shop. They say it's done!
They say it was an easy rebuild because it was in very good shape, and
out of sheer pity they decide to charge me $36 for cleaning/checking all
three heads instead of $28*3 :-) so the total comes to $135. So I figure
ok, $150 for the head, $135 for the machine shop, $45 for a gasket set
and the 6 will be back on the road by the weekend. I get the head home
and notice that there are 3 studs in it for attaching the intake manifold.
My manifold bolts on (I start getting suspicious, but not too much). I
check the size and threads, they look ok. So I start looking for a couple
nuts to pull the studs out. Wait a minute. Something doesn't look right.
I frantically grab the intake manifold and take a closer look. IT'S THE
WRONG HEAD! My car is a '70, which has intake ports 5/8" apart; the head
is a '72, which has intake ports 7/8" apart. Scream, cuss, go out in the
driveway and throw several large rocks into the woods as hard as I can.
None of this moves the intake ports on the manifold or the head.
I assume that Aurora will not accept responsibility for this because I
should have checked the head before I walked out with it, but I didn't
know that there was a difference between '70 and '72. I brought my old
head in there and they gave me this one and told me it would work. Now
I'm stuck.
The big question for the TR6 gurus out there: since the only physical
difference between the heads appears to be the the spacing of the intake
ports, can I make use of this new head by just switching from my '70
intake manifold to a '72 intake manifold? Or would other changes have
to be made? I can't find any information in Bentley's, Hayne's or
Chilton's about this. TRF's parts catalog lists 2 heads, the earlier
one being 8.6:1 compression and the later one being 7.75:1 (no mention
of intake port spacing). Should I infer from this that the new head I
have, since it is definitely not the same as the old one, must then be
the low compression one? At this point do I care? The new one also
has an pair of springs per valve instead of one spring per valve like
the old one, but it looks like that was just an improvement that doesn't
cause any incompatibilities. Any ideas?
I'm really hoping to make use of this head since I have $285 invested
in it. I guess as a last resort I could hang on to it until someone
out there cracks a head on a newer TR6, but that doesn't sound like a
very satisfying solution. Not to mention that I would have to start
the search/fix process all over again.
AAAAAAAAAAARRRRRRRRRRRRRRRRRGGGGGGGGGGGGGGGGHHHHHHHHHHHHHH!!!!!!!!!!!!!
Tim
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