Sump gaskets (no, seriously, GASKETS this time)

[Fingolfin]

Well what do you expect me to do on the third try, for goodness' sake? I've clearly been doing something wrong, but since American mechanics give my car funny looks and there are no other Minor owners in the area, I've got to go it alone (with your telepresence). May as well give all the advice a try!

Oil was definitely leaking down the front and rear faces of the sump. There's some minor weeping from the bellhousing pin, probably because the PCV nipple into the inlet bore needs a larger internal diameter (as you've suggested in the past, Roy), but it's not nearly large enough to account for the six (US) pints I lost in 135 miles two weeks ago.

[philthehill]

Ignore the thick thin argument. So long as the cork seal is a snug fit between the seal side retaining walls, it protrudes no more than 1/8" above the sump top face at either end, the cork is well above the seal side retaining walls and you have greased the cork seal that is all you can do. If you feel comfortable with using sealant and it stops the leak that is OK by me. It is more important to get you back on the road than worry about procedures.

[bmcecosse]

I'm sure I have read in the past that some folks soak the cork in either water - or perhaps engine oil - for 24 hours before fitting. Never done that myself...but maybe worth a try. But as I remember - I always had to squeeze the sides of the cork slightly with fingers to make it fit down into the sump ends...... The point about a 'procedure' is that if followed - it WORKS!

[philthehill]

As fingolfin has viewed the workshop manual and followed the 'procedure' (see his posts above) it has clearly not worked for him; so following the procedure is not the be and end all in this case. Hopefully now having suitably sized cork seals it will work and whilst I agree there should not be any need for sealant it will not do any harm.

[Matt Tomkins]

I'm sure I have read in the past that some folks soak the cork in either water - or perhaps engine oil - for 24 hours before fitting. Never done that myself...but maybe worth a try. But as I remember - I always had to squeeze the sides of the cork slightly with fingers to make it fit down into the sump ends...... The point about a 'procedure' is that if followed - it WORKS!

putting my cork seals in (i was in the privalaged position of having the engine on the bench upside down with the front and back plates off) i squeezed the cork in the vice, so it was consistent all the way across, before putting it into the grooves. I cleaned everything with a blade to within an inch of it's life then degreased it. i must admit i then also put a thin smear or hylomar on either side of the paper gasket before clamping it gently up. i've subsequently painted the engine with all the gaskets in-situe (not the neatest/crispest way, but as it was done in the factory) hopefully providing a full belt and braces approach.

[IslipMinor]

Whether BMC used gasket sealant in the original manufacture or not, Rolls-Royce certainly did! They used blue Hylomar on gaskets used between non-machined surfaces.

As a general rule I would always use a smear of sealant on the non-machined side of gaskets, i.e. on the rocker cover side of the gasket and the sump side of the gasket. Then an even smear of grease on the machined side, i.e. the engine block. Assemble whilst the sealant is still wet so that is acts as a glue between the rocker cover/sump and the gasket.

Doing this on the rocker cover gasket means that the rocker cover comes off very easily, and the grease ensures that it does not stick. The sealant makes the gasket adhere to the rocker cover, so lifting it off is extremely easy, and the gasket can be reused 2-3 times with no leaks at all.

On gaskets between machined surfaces I use smear of grease on both sides (not on the non-copper head gasket of course). Again the grease makes disassembly very easy should it be necessary.

[katy]

I'm sure I have read in the past that some folks soak the cork in either water - or perhaps engine oil - for 24 hours before fitting

I've done the "soaking in water" on cork valve cover gaskets that had shrunk so much that that was the only way to install them w/out breaking them. On one occasion, soaking too long expanded them so much that they were too large and had to be allowed to dry and re-shrink before installation. FWIW this was on GM diesels.

[Matt Tomkins]

Whether BMC used gasket sealant in the original manufacture or not, Rolls-Royce certainly did!

what an excellent point!

[bmcecosse]

Yes , and I even have a tube of ex RR Hylomar - 'donated' to me by an employee. And yes - I do glue the rocker cover gasket to the cover - not for any sealing purpose - but as Richard describes - for multiple re-use. I have used the hylomar on thermostat gaskets - to allow easy dismantling and reuse of the gaskets when changing 'stats. Otherwise - wipe of grease perhaps - not for any sealing purpose - but again to ease dismantling and possible reuse of gaskets - particularly timing case.