Subject: TR4 Compression - Follow-up
Author: lti@garnet.msen.com (Limno-Tech Inc.)
Date: 12/28/94 10:31 PM
>Thanks to all the kind folks who provided technical advice on my question
>regarding low compression in my #1 cylinder. I pulled the head and found
>all of the exhaust valves to be fairly fried looking, and the #1 valve
>actually sitting below the level of the combustion chamber surface. My
>local machine shop bead blasted the whole mess, took it apart, and found
>that the only things that need replacing are the exhaust valve seats and
>all of the valve guides. Surprizingly (to me), they said the valves
>looked fine, met specs, etc., and recommended cleaning them up and reusing
>them.
In my jaded opinion, it's not worth saving $40 to have an old exhaust valve
go south not too long after putting the head back on. Why not spend the $40
and put new exhaust valves in? I've decided the next time the head comes off
my GT6+ (which will come sooner than I want, I'm sure) I'm replacing ALL the
valves and springs. I had the head for my GT6+ rebuilt a year ago, and I let
them put the old valves back in. I lost an exhaust valve recently, and had to
pull the head again. I only replaced the bad valve, but next time I'll do
the whole shebang. Now, I'm not saying the valve was bad, but I'm suspicious.
I DID find out that my rear carb was way too lean, so who knows...
>
>While I'm waiting for my parts shipment, I am de-carbonizing the piston
>crowns, and generally cleaning up everything that I had to take off of
>the car to pull the head. I am also thinking ahead to reassembly time,
>and would appreciate opinions regarding:
>
> 1. Suitable sealants for the head gasket and other gaskets
I used the blue Loctite gasket sealer in the spray can that VB sells, and
I've never had any gasket leak when it's applied properly. When I pulled the
head on my GT6+, after 1 year, about 9,000 miles, it showed no signs of
leaking. And that's with me driving a bit with the head nuts way under-torqued!
Dumb me, I torqued the head nuts according to 1.6-liter Vitesse specs (40 ft-lb)
instead of GT6+ specs (70 ft-lb). Still no leaks!
> 2. Threadlocking and anti-seaze products for the various fasteners
I didn't use these. I just torque the nuts according to spec, and I guess
they come off too frequently to seize up ;^)
> 3. Best method for cleaning up the outsides of the carburators without
> going to the extreme of polishing them to an (IMHO) unnatural shine.
I just cleaned them off with carb cleaner. A problem I seem to have every time
I pull the head on my car is that the carbs dry out, and the floats stick for
a bit when I first get it going again. They clear up pretty quickly, though,
usually with a tap from a rubber mallet...
>
>Thanks again.
>
>==============================================================================
>Dean Mericas
>1965 TR4 (CT37089L) -
>dmericas@limno.com
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