The Triumph Dolomite Club - Discussion Forum

Having had issues getting the water passages to seal when refitting the inlet manifold on Binny (1850 Dolomite) I thought it would be interesting to compare the new blue grey ones against red-ish NOS style ones.

The difference in thickness is really quite large...

Red-ish NOS ones - 0.0215" (about 22 thou on average)
Blue gray ones - 0.065"

About 3 times thicker!

It's some years since I bought some.
The first were purchased from Rimmer Bros, they were made of very thin paper - I didn't fit them, they just didn't look right.
I then bought from TD Fitchett, the gaskets were much thicker. Used them, no issues.

I recently fitted a Rimmers blue manifold gasket to Rich's Sprint. Both head and (Weber) manifold were spotlessly clean and appeared, to all intents and purposes, flat. It leaked like a sieve, as soon as the coolant level reached the joint, without even starting the engine. I had to remove the manifold again and ladle a load of silicone round the water gallery before it would seal and hold running pressure! I wasn't impressed! But i'm at a bit of a loss as to WHY? Is the paper they are using somehow uneven in thickness? Or porous? It doesn't make sense!

Steve

Carledo wrote: ↑Sun Jul 08, 2018 9:09 pm It leaked like a sieve, as soon as the coolant level reached the joint, without even starting the engine. I had to remove the manifold again and ladle a load of silicone round the water gallery before it would seal and hold running pressure!

Exactly the issue I had the first time I tried to refit the manifold on Binny.
I might make enquiries with some gasket companies about getting a batch closer to the original thickness made up.

Both 1850 and Sprint inlets have in my opinion a missing bolt; ideally they both need another in the bottom right corner to effect a good seal to the water jacket. My thinking is a thicker gasket is able to be compressed by the bolts and should therefore be a better option...EXCEPT in the bottom right hand corner where the missing bolt cannot do its job. A thinner gasket has less compressibility and therefore the manifold gets a more even interface with the head and no leak.

I fitted one from TD Fitchett a few years back when I swapped the inlet manifold. It hasn't leaked ever since.

The redish gaskets were the ones that are in "payen" gasket sets therefore good quality. You to get spurious makes of gasket sets years ago and they would not either I shudder to think of all the gaskets i have thrown away over the years.

Tony.

Reddish = asbestos containing gasket.

It was good stuff in so many ways, that asbestos!!

xvivalve wrote: ↑Sun Jul 08, 2018 10:33 pm Both 1850 and Sprint inlets have in my opinion a missing bolt; ideally they both need another in the bottom right corner to effect a good seal to the water jacket. My thinking is a thicker gasket is able to be compressed by the bolts and should therefore be a better option...EXCEPT in the bottom right hand corner where the missing bolt cannot do its job. A thinner gasket has less compressibility and therefore the manifold gets a more even interface with the head and no leak.

I think the thicker gaskets can also prevent the O ring between the head and the manifold getting sufficient clamp to stop the front waterway leaking into no #1 inlet.
I'd like to meet whoever left that long waterway slot in the head at the rear and shake them warmly by the neck!