Sump gasket

[Bob Culver]

The recommendation to regularly remove sump and gauze stem from the days of non additive oils when cars subject to short runs generated inches of sludge.
For my Austin and two successor cars of 50s and 60s I have always cut gasket from sheet cork, preferably reinforced or rubberised. Works even with short pieces butted. If cemented to one face can sometimes reuse. In the enthusiasm of youth I used to remove at every change. Need occassional tightening so not favoured commercially. 

With Sevens there is no filter before the pump so vital that no cork chips or goo blobs get into sump, and that the gauze is not holed. As before many sump leaks are due to threads breaking into fluid. These need a fibre washer or possibly thread tape if can gaurantee none ever gets into sump.

Newcomers often do not realise that threads provide a helix aperture and if not into blind holes or sealed under the head will leak surprising amounts.This is rarely mentioned in texts and is often not self evident. For decades I ran a Javelin car. These are prone to leak water up the head studs and into engine and I ran pints through before the source was identified (no damage, but do not try with ball bearings)! And it was years before  all the oil leaking threads were identified.

[Tiger]

Bob
Thanks for a very compressive answer.
I am just about to fit the sump.
I was going to try fibre washer followed by steel ????

[Bob Culver]

If using a plain steel washer as well it must be atight fit and seal the screw shank, problematic with a setscrew (bolt threaded to the head)

[Timothy P]

Maybe a stupid question but I can't recall for certain aren't the sump bolts in blind holes in the crankcase? I know most are, but can't recall if the front ones are too? If they are and if the gasket joint is OK then no oil should be anywhere to track up the threads, with a tin sump I think I'd prefer to use the correct mildly spreading washers to help spread the load on the flange in the hope of it staying flat.

[Timothy P]

To correct myself early crankcase are 'undercut' around the inside and as such the sump bolts are not in blind holes (at least not all of them). Later crankcases don't appear to be undercut in the same way and as such appear to be blind holes (at least for the most part). Sorry I can't pinpoint when the change was. Further correction of course welcome.

[Bob Culver]

Over the decades  screws of wrong length get fitted and often  break out the base of threaded hole. I would not fit fibre washers to every screw.

[Tiger]

All the fixing holes for the sump are blind.
After consideration I have fitted oblong washers.
The sump flange and crankcase joint are perfectly clean.
Also dressed the flange to get as flat face as possible.
Using A7 workshop paper casket with cement.

PS one way oil could seep along the studs is if the inner joint face fails
providing a route to the stud thread .

Many thanks for all the replies

[Zetomagneto]

All the fixing holes for the sump are blind.
After consideration I have fitted oblong washers.
The sump flange and crankcase joint are perfectly clean.
Also dressed the flange to get as flat face as possible.
Using A7 workshop paper casket with cement.

PS one way oil could seep along the studs is if the inner joint face fails
providing a route to the stud thread .

Many thanks for all the replies

If using goo, you might as well leave the gasket out then you only have 2 surfaces to seal, not 3.
Modern engines do not use a gasket, they use a sealant, I have used a Mazda sealant in the past on a Mazda MX5 it was very good stuff and the squished residue inside the engine does not easily break off.
The last thing you want is bits of sealant in the oil Jets