365 Gearbox leaks.....

[TCs Euro]

Hi All,

I have a few leaks from my 365 gearbox

1. Output shafts.
2. reverse/5th gear detent shaft. There is quite a lot of play on this shaft
3. Gear selector shaft. There is quite a lot of play on this shaft

All 3 leak when not being used, so quite significant leaks. I filled up the gearbox, level to the fill point. Left it on the ramp for a few days, the result was pools of oil on the floor,  about 6 to 8 inch round pools.

New seals were fitted by a 'Lotus specialist' at the rear of the gearbox. But seem worse than they were before....

My question is.... obviously play or movement on these shafts isn't too good for sealing, has anyone re-bushed the openings/housings and fitted new seals to suit these bushes and shafts? What are peoples thoughts? Obviously a bit of machining would be required....

Cheers Jay.

[4129R]

Leaks
Oil
Through
Unusual
Sources

I have seven. They all leak somewhere.

[BDA]

They do all leak but a 6 - 8" puddle is extreme. I know the 365 commonly leaks from the selector shaft but they should not leak from the output shafts. There is a seal for the selector shaft which I assume can be changed without too much trouble after taking the end cover of the tranny off. The detent plugs have a sealing washer. You could smear silicone or Hylomar on the threads of the plug to keep oil from leaking from there.

Can you tell where the leak is coming from at the output shafts? Is it leaking from the threads of the finned nuts or the seal at the output shaft. In the first case, the O-ring seal for the finned nuts is worn out. In the second case, the seals can be replaced again. I might give the "Lotus specialist" an opportunity to fix their mistake and if they don't, I'd never go to them again. I might look for a Renault "specialist" then.

[Grumblebuns]

I'd be a bit more concerned with play in the gear selector shaft, Is the play fore to aft or side to side? 

[jbcollier]

It sounds like you are saying that the shifter shaft and the reverse/5th detent shaft both have play and move sideways in their bores.  New seals will not fix the leaks until the play is removed.  You will have to remove the rear housing to do so.  There are brass bushings for the shifter shaft. Early ones are 15mm ID and later ones 17mm.  The detent shaft doesn’t have a replaceable bushing so the housing will have to bored and a bushing made up to suit.  The housing is weak in this area so be careful.

Output shafts often weep a bit and it is not a concern as long as accumulations are moderate.  Seals and seal run o-rings are readily available.  You need to be super #%£-ing careful when replacing them as it is VERY easy to screw up the diff bearing preload and the ring gear backlash!!!!

I would start with repairing the rear cover and re-evaluate you leaks after that.

[TCs Euro]

Thanks All,

Informative advice as ever.

The play is sideways on both shafts. Gearbox end cover coming off and new bushes and seals on both I feel is the only way.

[jbcollier]

Read the manual before removing the rear cover.  You can drop selector shaft detent ball inside the transaxle if you are not careful.

[4129R]

Read the manual before removing the rear cover.  You can drop  selector shaft detent ball inside the transaxle if you are not careful.

I did exactly that, and it took me ages to get it back together even with the gearbox out of the car.

[TCs Euro]

Noted...