I am touring northern Spain and France just now in the Chummy with the family, see below, having a great time.



Every couple of days the gearbox is emptying itself - this first happened as we crossed the Pryanees into France. I assumed that 40°c heat and first gear for over an hour on climb and then again on descent had boiled the oil and that was the cause. However, every couple of days or 300/400 miles since, I have to top it up as it is almost empty.

I have not experienced this before - any suggestions as to why it is disappearing so fast? The engine deposits no oil normally but clean (gearbox) oil is pooling underneath the gearbox/bell housing gap.

I have some miles yet to travel but will continue to check and top up - any thoughts on what might have failed to cause this?

I wonder if it is a problem with the blind bush at the front end of the mainshaft?
Is there any other way that the gearbox oil can get into the bellhousing?
My saloon went through a period of doing the same but seems to have cured itself. Yes there is some oil in the gearbox!
Looks as if you are having a great time.

You look to be having a great time Ruairidh.

If the gearbox oil is leaking away through the gearbox/bellhousing gap then it follows that it must be coming out of the front of the gearbox. So, most likely culprits are gearbox casing/front cover gasket or the front cover/first motion shaft seal (if the box has one rather than the later scroll). I suppose a loose front cover stud might also be a possibility but that's a bit more unlikely. Assume you've got engine oil in the gearbox so, maybe, the higher than normal temperatures are causing it to be thinner than normal such that it can exploit any route for escape and if the gearbox does have a scroll rather than a seal, maybe the oil is getting that thin that it's beating it. I can't see what you can do about it other than taking the engine and gearbox out to investigate - whilst you do have four 'labourers' with you, perhaps not a route to explore unless you really, really, really have to!!

If you could get some thicker oil, say straight 50, then that might help but other than that, and assuming the clutch isn't getting contaminated, as the saying goes, keep calm, carry on and keep topping up (also known as FIDO)

Steve

Location: North Yorkshire

Hi Ruairidh,
Thanks for the pictures and we all wish you all to keep having a good time!
Steve and Malcolm have covered most points but we all need to do a bit of brain storming in advance of you maybe having to pull things apart. My first thoughts were also about the blind plug in the spline but that would have chucked oil on to the clutch, which appears not to have suffered. With the top inspection cover off is oil thrown inside all of the bell housing as if coming along the spline? If not the leak is from the cover as suggested. If you have a felt seal that has packed up it would drip from the drain hole in the seal housing. A further thought to offer (not a nice one!) is a crack in the front cover somewhere (say) under the roller bearing housing.
During the long haul in bottom gear quite a bit of local heat may have arisen where the third motion shaft spins inside the first motion shaft. This may have allowed the plug to "lose its grip" or cause some other problem - but I can't think what that might be!!
Hoping for the best for you
Ron

All looking like a great adventure.

If it were my problem I would be tempted in the warmth ect to put EP90 gearbox oil in. I use this in all my cars and have never had a problem despite people telling me that it would cause problems.

You might become a covert!!

Location: The Centre of the Universe

Thanks for all the suggestions - to be clear, I don't intend doing much about this (other than topping up when needed), until home. It is a new issue to me, I shall report back once home and having followed up your suggestions.

Thanks.

If it's coming out of the input shaft, either by way of the core plug or a faulty seal, I'd expect you to have a seriously slipping clutch by now. My guess would be a cracked or loose front cover plate. Unless a really stupid suggestion, do you have one of those bits of tinplate that fits round the gearbox drain hole and plugs up the bell housing hole? It's not a loose drain plug that looks as if the leak comes fro the bell housing if you see what I mean?
Good luck, that's one of my favourite parts of the world!

Our chummy box does this on holiday too. Most strange, but perfectly liveable with. Every year, in France for the last 10 years or so I have had to top it up. I assume it's a combination of ambient temperature and the fact that the dream holiday for 3 speed boxes is a daily oil change, gearbox equivalent of a spa break I guess. Once the last top up at the end of the trip is done it lasts all year, with plenty of use, until the second or third day in the dordogne 11 1/2 months later! Who can blame it?
Have fun, W

Yeah I tend to drink a lot in France, too.

Very reassuring on both counts - merci!