I see that C15 sump plate sealing is a topic that has come up before... with the studs also under suspicion....
Has anyone found a solution that works? (Other than a drip tray!)
My B40 plate studs leaked for eons, around one corner/stud.
I'd tried wet sanding the sump plate on a glass plate, and checking all faces with the side of a steel ruler, with no success, but tried again last winter. This time it has worked, but I suspect the new slightly thicker softer gasket is the reason....prob just enough to deal with residual unevenness around the stud.
I believe just tightening the plate a bit too much can distort the alloy around the stud on the case..aiding a leak....with that lip then hard to file off with the stud in situ.
Hi,
Remove the studs and really clean/degrease the threads on the studs and in the case. Very slightly countersink the the stud hole - a twist with large drill by hand will probably be enough to just remove any raised material. Use some thread lock to secure and seal the threads. Do not over tighten the nuts. For that size of nut a spanner about 5" long is more than enough for leverage and use a nylock nut so over tightening is unnecessary to ensure that the nuts do not come loose.
Dave.
I find a hand countersink like this very useful for this kind of job.
(https://cdn.aws.toolstation.com/images/141020-UK/800/76122.jpg)
hoogerbooger - Can you by any chance remember the colour of the gasket material. Might help me in my search for the thick soft one....
Searched my email and it was on an 2025 order from Feked. Link to part here:
https://www.feked.com/bsa-sump-plate-gasket-c15-and-b40-models-circa-1959-65.html?srsltid=AfmBOoq5wUyhasU4XKw6BDpevZofPqIUI2nUgrLLBZ4EgCPS10BGrzwR
Looking at my sump plate I can still see that the gaskets are greeny/blue....so I'm fairly sure the picture on the Feked link is what I bought.
( my previous gaskets were ones I cut from gasket paper, which seemed to have little give)
For my A10 I used hylomar both sides of both gaskets so its gasket-plate-gasket-sump. I also had to helicoil the case (1/4 BSW) as two of the threads were stripped. You want to just squeeze up the gaskets, not clamp, as the soft gasket allows the steel plate to deform and then it leaks. In my experience these are always damp with oil, if its just a few drips I leave it alone.