Triumphrat

Rochdale Cowboy · 04-28-2011, 03:50 PM

In my experience if the head gasket fails, the dramatic loss of compression shuts the engine down and won't restart until cold, then if it starts maybe only 1 cylinder until the heat opens up the gas seal again.
In my case the damage was minimal, but I had a 3 mile push home!
Mine had around 24k miles at the time of failure.

RC

cram108 · 04-28-2011, 04:30 PM

well then I guess I'm gonna push my luck I guess!! You'll be hearing back from me if it failed. I hope you guys enjoy giving advice cuz I'm gonna need it.

lovecuba · 01-04-2013, 07:03 PM

Quote:

Originally Posted by Rochdale Cowboy

Sorry Caulky, but the some of the info you provided needs correcting.
The 2 inner studs are 5/16 diam and sleeve nuts with 3/8 a/f hex drive.
These need a dry torque setting of 16 ft lbf.
The inner rocker studs are 3/8 diam and sleeve nuts with 3/8 a/f drive and need a torque setting of 18 ft lbf.
They need the hex driver tool, or a hex key, 3/8 ring spanner in a torque multiplier mode. I made a hex key and 1/2 sq drive to go straight into the torque wrench as the head room between rocker box and frame is not enough. Removal of the rocker boxes is a least favoured option as all gaskets will need to be disturbed and renewed.
The outer hex head bolts are 9/16 a/f and are torqued to 18 ft lbf.
The service info for torquing a new composite gasket is tighten all 3/8 to 22 ft lbf and 5/16 studs to 18 ft lbf, fire her up to full temp. When cold they should be retorqued to the 18 for 3/8 and 16 for 5/16.
Reset the tappets and after 500 miles, retorque the head again to the same values.
It also begs the question whether the cylinder head gasket, having leaked, can be trusted to seal at all after all this work has been done. If the original overhauling was incorrectly carried out the head may be warped or studs stretched?
If you were to look at the sealing area between the 5/16 studs and the bores, you'd appreciate that little needs to go wrong and it all goes wrong.
i don't want to sound unduly negative here, but this is why we have forums to share opinions.
All the best with whatever you choose to do.

Are the figures for torqueing up with a new composite head gasket correct?

Rochdale Cowboy · 01-05-2013, 03:37 AM

Yes, I got this detailed info from a technical bulletin that Triumph issued to dealers for introducing the new composite "Klinger" gasket.
The workshop manual figures are correct for the annealed copper gasket.
I'll try to find a copy of the technical bulletin, which also outlines the retightening process.

The bulletin is 9-79 and it also advises that the metal bridge between the cylinders is uppermost to the cylinder head face, not into the barrel sealing grooves.

lovecuba · 01-05-2013, 02:45 PM

Cheers RC. Much appreciated.