As many of you will know, sealing the exhaust pipes to the cylinder barrels can be a problem, resulting in sticky black goo dripping from the joint, particularly on 4T engines.
The problem is the composite ring gasket, originally these were made with asbestos filling but with that now banned, the replacement material used in these is not as good, this coupled with the size of repro ones being of smaller section results in a poor seal.
I made some solid ones up or my 4T engine some time ago and after initial bedding in they do not leak, I made mine out of soft aluminium, but a alternative material would be copper. I attach a drawing for the ring, which you will see has a square profile thus giving a larger sealing area. Before fitting, and when refitting exhaust system, the copper ones should be annealed by heating on a gas ring to a dull red & quenching in water, this softens the copper so it beds in to make a good seal. This type of solid gasket can be used several times where as the old composite ring needs replacing each time the exhaust is dismantled.
The problem is the composite ring gasket, originally these were made with asbestos filling but with that now banned, the replacement material used in these is not as good, this coupled with the size of repro ones being of smaller section results in a poor seal.
I made some solid ones up or my 4T engine some time ago and after initial bedding in they do not leak, I made mine out of soft aluminium, but a alternative material would be copper. I attach a drawing for the ring, which you will see has a square profile thus giving a larger sealing area. Before fitting, and when refitting exhaust system, the copper ones should be annealed by heating on a gas ring to a dull red & quenching in water, this softens the copper so it beds in to make a good seal. This type of solid gasket can be used several times where as the old composite ring needs replacing each time the exhaust is dismantled.
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