Sump oil leak

[7skypilot]

I use Cometic gaskets on my engines (BD's and a Twin Cam) everywhere except the twin cam front cover. The Twin Cam is oil-tight to the extent that some of the sump bolts are showing signs of rust!

The Cometic sump gasket will mate perfectly with rubber front and rear seals from a Kent (711M) gasket set, but the front seal needs to be reduced in thickness to fit the groove correctly. A tiny blob of sealant at the junction of the rubber seals and, hey presto, a cork-free sump. No need to stick the cork to prevent movement, or to tighten the sump bolts as the cork compresses. It really is a good solution to a rather messy problem.

I also replaced the sump bolts with cap-heads for easier removal. I might use stainless cap-heads next time to avoid the rusting problem!

[daverubberduck]

This forum is amazing, I honestly don't know where I would be without it.

Ed - I can't compare the cleanliness because my engine oil is pretty clean at the moment, but the oil from the back is definitely thicker than engine oil. My chassis is a standard type, not space frame. The gearbox itself seems dry and no oil dripping from that part of the car. Tried shining a light down the tunnel but it was difficult to see anything. Thanks for the tips, I will make a note of them for when I get round to doing the job.

Thanks Rohan, I'm relieved to read your post, I was thinking I would have to do it now. To be fair I have had the front jacked up for a while and the puddle has appeared quite slowly, so perhaps no panic but a job for the future. I have now lowered the car pending the arrival of the helicoil kit.
cheers
Dave

[billwill]

If you take the right hand seat out and the tunnel cover off, there should be a hole through the body and chassis so that you can reach into the tunnel.

It may have a big rubber bung in the hole.

Its main function is so that you can reach in to insert the yoke of the propshaft into the gearbox when reinstalling the gearbox but you can also use it to inspect for leaks by feel.

[daverubberduck]

Ah now that's interesting. Just found this pic on Kelvedon's site, I presume that is what you mean. I'm guessing that I would have to cut a hole in that material that goes over the backbone but that's no problem. Worth knowing about, Thanks Bill

[billwill]

Yes, that's it.

Some carpet layers might not realise that hole is needed so if you had replacement carpet it might not have the hole in the carpet.

[RichardHawkins]

Rohan,

Thanks very much for taking the trouble to reply to reply, and explain your reasons. So if I persist with silicon, the important thing is to be sparing with its use.

Thanks once again,

Richard Hawkins

[RichardHawkins]

Rohan,

I thought I had replied to you earlier, but when checking, I can't find my reply.

Thanks for taking the time and trouble to explain your reasoning. I conclude that when using sealants, particularly silicone, that I need to be sparing, and use the minimum possible.

Thanks again,

Richard Hawkins

[daverubberduck]

Hi Rohan
I have been unable to find (in the UK) the Loctite no3 adhesive that you mention, and almost every sealant/adhesive that I can find is silicone. The only possible alternative I have found so far is Permatex 80062 High Tack Gasket Sealant. It looks like the same thing so I will probably go with that, unless you tell me different.
Dave

[rgh0]

This high tack sealant is a new product from Loctite / Permatex that i have been wanting to try. Yes as far as i can tell it is like the No3 Aviation gasket sealant but is stickier to hold the gaskets in place even better during assembly.

If you left the No3 aviation gasket sealant for about 15 minutes after application and before assembly you achieved a very sticky sealant as it semi dried, the high tack sealant is supposed to achieve this on application without having to wait so long.

let me know how you go with it

cheers
Rohan

[daverubberduck]

thanks Rohan, I'll let you know

[daverubberduck]

Hi Rohan
It took me a long time to get round to this job, partly because of other jobs getting in the way, partly because I fell off a ladder in the garden and cracked a rib which made it very painful to crawl under a car. Anyway, I've done the job (reminder: mend oil leak in sump by removing sump, repairing stripped thread into front cover and re-assembling) and I've just finished putting it all back together. Haven't run the engine yet but hopefully no more leaks. The Permatex sealant seemed to work well. I cannot compare it with what you use because I have only used this stuff, but it is a very gooey red liquid and seems to be tacky pretty much as soon as you apply it.

Overall the job went well and next time I think I could do it much quicker. Thank you to everybody who gave advice on this. I was worried about doing this job - perhaps that's why I jumped off the ladder . Sump took a bit of shifting but it came away in the end. I do have one question about the anti roll bar - how far do I tighten up the nut at the bottom of the stack of washers and bushes. I have searched for an answer both here and in the manual but cannot find it. One thing I did find was that there should be 2 nuts, the second being a locking nut. I seem to have just one nyloc type nut. Anyway, does this nut tighten to the end of the thread or should it be locked at some point before the end of the thread?
cheers
Dave

[rgh0]

Glad the sump went well.

I normally tighten up the shock nuts to be close to the end of the threaded section. The precise length of the plain section versus threaded section I have seen vary over the years with shocks of different makes so I now tighten until the rubbers look nicely compressed on some shocks that bottoms on the thread on some it does not

cheers
Rohan

[daverubberduck]

Many thanks Rohan.
Dave

[Hawksfield]

Hi Dave / Rohan

I have just used the permatex 80019 (Aviation form-a-gasket sealant liquid) to install my sump and the timing cover to head cork gasket. results are excellent and oil tight. As stated take your time when using and let it thicken before sticking on gaskets. available on ebay

Dave the sump can be removed by just dropping the drop links from the chassis and letting the anti roll bar fall to give clearance

See photo taken through access hole in chassis

[daverubberduck]

The main problem I had with removing the sump was just that it was stuck on. I didn't want to damage the edge of the sump so it was just a matter of running a Stanley knife along the gasket, gently prising it with a short screw driver, and gently hitting it with a hammer + piece of wood. I had to do all these things several times before it came away, and no damage done.