Dean Paige wrote:
>
> 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
On the engines that we build , including the 14.5 to 1 race bullets , we
start the engine and let it get to 190 . The bolts are then retorqued
hot and the valves set , hot . We always set the clearances hot because
thats how the valves operate . Presumably the factory gives cold
clearances so the techs don't burn their tinkies , we big hairy-chested
types don't worry about a little heat do we ? ( sorry for the
testosterone laden comments all )
Kevin Allen
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