Does anyone on here happen to know the proper thickness of material for a 2000/2.5 sump gasket? I seem to remember those I had in the past were about a sixteenth of an inch thick, whereas one just purchased is cut from much thinner gasket paper, perhaps only 1/32” in thickness, and I am a little concerned as to whether the thinner material will provide sufficient compression to allow the gasket to ‘pull down’ and so provide a reliable seal.

If – as I suspect - the 1/32” paper is too thin for the job, any ideas as to likely sources for individual gaskets of the appropriate thickness as opposed to complete bottom-end sets? Having suffered the existing gasket oozing oil for no apparent good reason after only a relatively low mileage, I don’t want to risk fitting a substandard replacement and find that the problem reoccurs...

Suggestions gratefully received!

Regards,

Hello Jonathan,

I think you are right. The options are to use a modern silicone sealant as well (I know not everyone likes this material?), buying the material and making your own. Rather tedious without wad punches and even then is a lot of work, or trying to source a thicker gasket without buying a whole set?

Alec

No choice really than to use what you have. The "key" ! to any gasket seal is to have absolutely flat, clean surfaces, with no distortion of the bolt holes. The front and rear alloy bridge pieces must have excellent threads / otherwise helicoil them all. It no use hoping for the best - when its too late to go back. I tap out bolt holes - slightly convex - on the sump and timing cover etc, and check faces with a straight edge. This is worth the extra time and effort; its the last step in an engine build. I fit my gaskets wet ( except the head ! ) and may use some copper slip. The gasket will then not stick hard to the block etc and can be often be re-used as race engines are always being worked on. I know a dry gasket is supposed to swell ( with the oil ) where there are any gaps or potential leaks, but my method has been very reliable.

Alec, Steve,

Thanks both for your replies and suggestions. I'm pretty sure that the problem is not the bolts into the bridge pieces (already checked there!) but general seepage along the length of the gasket - it looks as if it is soaking up oil from inside the sump but for some reason failing to become oiltight once wet.

I don't remember any undue bellmouthing of the bolt holes in the sump when things were last apart, but evidently I need to look again. No problem with using a sealant like Hylomar in this location, but obviously want to be reasonably confident that the thinner gasket is up to the job!

Thanks again.

Jonathan

Jonathan,

Hylomar may do the job, but I'd prefer to use a soft-setting liquid gasket of the type that's normally intended as a gasket replacement. Hylomar was used on the sump-to-block interface on the Rover 2000, with no gasket at all, but the sump was aluminium with a machined face. The pressed steel sumps on our Triumphs are more problematical, having very little in the way of flat lands.

I use a soft-setting 'liquid gasket' on almost all engine and gearbox gaskets (and the fixings that pass through them) and no leaks ever occur (I'm talking of 30+ years of doing it this way!).

On the rocker cover gasket, I apply the 'liquid gasket' to the underside only, so that it semi-sticks to the top face of the head but allows the cover to be removed at a later date and then refitted without problem. An '0'-ring on each of the cover retaining studs, beneath a plain washer, ensures freedom from leaks from there as well.

With reference to the recent discussion about whether or not to re-use Nyloc nuts, I've renewed the ones holding the rocker cover only once since I bought the car in 1975 and they don't come undone. They now screw up and down the stud fairly easily using a 1/2" A/F socket on a hand-held 6" extension, but they stay where put. I wouldn't try this with driveshaft U/J nuts of course!

Back to Steve's comments - I thought I might be the only one that goes to the trouble of making the area around the bolt holes slightly convex. I use a small ball-pein hammer for this - hold it in position then tap with a larger hammer.

I know the 'rules' are not to hit one hammer with another as there's the risk of a shard of metal flying off into one's eye, but only a light hit is needed and safety glasses will remove any risk of eye damage.

I thought Steve's advice as to how to seal gaskets was excellent. My only question would be in relation to gaskets supposedly swelling in use so as to seal leak-paths. Most gaskets of the Triumph era were either cork or, more commonly, compressed asbestos fibre and weren't designed to swell so as to seal any gaps, though they may sometimes have done so to a small extent. At Perkins we introduced oil-swelling gaskets in about 1985, and it was mandated that they were to be fitted dry in order to work.

Can you get Loktite Master Gasket in your part of the world? Great stuff which expands (so they say) when compressed. Seems to work with both oil and water.

Hello all,

there is an inherent weakness in pressed steel covers, and thicker gaskets do tend to be worse in that respect as the cover is more likely to distort at the holes as the fastener is tightened. Was it BMC that used an extra shaped washer to spread the pressure along the flange to reduce this. I went to an aluminium rocker cover for that very reason, although it is slightly different as the distortion was not onto a solid surface .
With regard to tapped holes, I like to countersink them so as to eliminate any thread pull up.

Alec

As Alec has said, the sump flange is anything but straight and flat. Those 'humps' between the screw holes mean there is little 'flat' area to seal against. All to do with giving it strength I guess and why the original gasket is much thicker. (I may have a 'new', original one at home - Jonathan, whould you like me to measure it?)


David, do you mean convex or concave? The latter seems a much better idea to make sure no threads are protruding. Or maybe I have misunderstood, as usual!

In terms of gasket 'goo'. I always used to use Wellseal, which I think was used in the Factory and was recommended by the local Triumph Agent, (who was also a friend!). I have tried searching for it in the recent past - is it still around?

Cheers,
Mike.

Jonathan

Sorry to be slow posting a reply to your question - had the family down for a long weekend and I had to give my son-in-law a hand assessing the body condition of his rear engined caravannette German thingy prior to us working out a restoration campaign on it (it is 'stored' with us).

Just been out to the shed and checked my 'stocks' of original spec gaskets (Payen) and the sump gasket in the conversion kit for the 6 cylinder Triumph (PI/TR6 etc) that I have is definitely a thick one.

Pop over to have a look if you want, and if you need one now to sort a job out you are welcome to have it and replace it at your leisure - won't need it for some time .........

Ted

Thanks, Mike - very kind of you. If you have one easily to hand to measure, that would be great, but please don't go to any trouble.

You can still get it in a toothpaste-style tube from Moss (http://www.moss-europe.com/Shop/, p/n 600569A). Ironically enough, the gasket which has failed was assembled with Wellseal, though I am not connecting the two - rather, I think that the gasket itself is soaking through, though I may yet be proved wrong in this assumption. I do believe that Wellseal is the only gasket sealant 'approved' for use with Laycock overdrives (and possibly B-W automatics as well).

Also very kind, Ted. The last couple of complete bottom end sets I've had have all been Payen which tends to confirm my recollection of a thicker gasket than those purchased 'loose' the other week. Thankfully, I'm in no particular hurry - at least not whilst the sky continues to have a sump leak of its own..

Regards,