leaky gearbox

Changed the oil in my gearbox in the last few days, but when I came to put the plug back into the extension box (the one that holds in the white plastic filter) it seemed not to tighten. I could get it quite tight before it seemed to cross thread and I coudl not get it so that I was really giving it some welly. It does not have a copper washer but has this rubber seal fitted.

It had not been leaking before I took it out so I just assumed that it must have been like that and that it woudl be ok. I had not experienced any difficulty getting it out or back in (i.e. I had not been the one that had cross threaded it so I assumed if it was cross threaded then it was working previously and not leaking).

Now its leaking and I can probably go under there each week and top it up but would rather not have a running bodge job. Do I have any choice other than to replace the plug??

its more likely aluminum housing that has buggerd thread rather than plug ,it should have gasket material washer,speed brace is the best tool for realinging a bolt etc with poor thread as you can hold it straight while tightening,unless oil is really bad i wouldnt remove that plug ,id get new plug and use speed brace and pray you can get it in square without totally stripping thread in case

Yep - upon inspection the thread in the gearbox extenion casing was badly "worn" - it is 27+ years old I guess. The solution was to get a new drain plug because the old one was also a little worn and I wanted to have the deepest possible thread. I then used some chemical metal on the thread of the new plug and it went in realy tight and no sign of cross thread.

I do realise that it will be a bugger to get out and that when I need to do so in a few years time I may be buggered but the way I looked at it was that the exisitng situation was not operable so using this approach buys me a few years and if I cant get it back out then I have to get a new casing but I was going to have to do that anyway as the thing was not holding oil!!

Thanks, Rich

just leave it in ,and change oil regulary(at least yearly) then it will never need filter removing r380 has similar filter but it can be removed