Hitchcocks Forum

Yes I know I'm a stupid, hamfisted buffoon!! Whilst tightening up the oil level check nut on the gearbox of my 350 Classic, I obviously stripped the thread, as it loosened off after it started to tighten.

After re-tightening carefully (stopping at the point before it went loose again) and leaving for a week, there was a very slight leak of oil coming from below the nut. Any ideas please?? Would a helicoil or something similar repair? Our hosts sell a replacement outercover which is about 60 quid, but this seems a tad drastic solution?? I'm assuming of course, that there's no oil pressure as such in the gearbox.

Any ideas gratefully received!!

well as this is a thing only being checked a few (if that) times a year , why not apply a thin layer of plumbers PTFE tape around the bolt

nothing lost?

Plumbers PTFE tape wound six or eight turns flat around the plug threads will prevent leaks.

or better still a dowty seal washer if the plug is shouldered... Sold by our hosts for the purpose of..

or better still a dowty seal washer if the plug is shouldered... Sold by our hosts for the purpose of..

sealing dowty,s


PTFE tape will be an effective fix

If it continues to leak pull the cover off and tap it out to a slightly larger thread, doesn't have to be the same type of thread, any thread you can get a bolt to fit will do, it is only a plug

I'd try the Dowty washer, they seal with very little torque - hand tight and a bit is usually enough. We used to use Dowty washers on high pressure gas cylinders and they were excellent. It might be worth putting a locking wire on to ensure it doesn't unscrew. I've done this to all my drain plugs as they are somewhat prone to stripping.
http://www.whfolk.co.uk/REOCHUMBER/Arti ... nplugs.htm

Or,

Make yourself a dipstick and araldite the level plug in!