Giles Nelson wrote:
>
> I'm afraid this is one of those `black magic' areas that the professionals
> don't even agree on.
>
> I had a similar problem with my TR6 about a year ago. I failed to re-torque
> the head until about 1300 miles after initially installed. The head gasket
> promptly failed at about 2000 miles. Bloody idiot!
>
> I was very angry at having to do the job again so was determined the gasket
> should not fail. After asking some TR specialists their consensus view was
>that
> a re-torque after 500 miles, cold, was all that was required and that 6
>cylinder
> head gaskets fail rarely. It is essential that both the block and head are
> absolutely flat. Warping of the block is rare, although possible. Cleanliness
> is also important. The replacement of head bolts is normally a good idea.
> I followed this advice - no problems since.
>
> Speaking to non-TR professionals their response included:
> bring engine up to normal working temperature, allow to cool, re-torque
> drive 5000 miles, re-torque
> don't re-torque at all(!)
>
> One would think that after 100 years of motor cars a consensus view would have
> been established for cast-iron engines! Alas no.
>
> Giles Nelson.
>
> 1973 TR6 PI.
Well just to be different this time I followed the instructions on the
head gasket. Torqued the head to 70 ft/lbs, installed manifolds etc,
cranked it over and it fired immediately. Ran the engine until it reached
operating temp and let it idle for another 5 mins. Shut it down,
immediately removed the rocker shaft and retorqued. Average of 15 to 20
ft/lbs difference. Reinstalled rocker shaft, let the engine cool a couple
of hours and readjusted valves. As per previous post after having the oil
changed Sun. morning took an afternoon country drive. All seems copacetic
at this point. Time will tell
Deano (Plop Plop Fizz Fizz) Paige
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