2500 Saloon gearbox and overdrive Oil leaks

[sulzerman]

Hi all 

Got some severe oil leaks on the gearbox and j type overdrive on my saloon, the underside of the car is dripping in oil!

There seemed to be alot of oil around the solenoid, dripping from O/drive sump and off the drain plug on gearbox.

Are there any parts which are prone to leaks? I dont want to remove the gearbox from the car!

I have got a new o/drive sump gasget (not yet fitted), I have changed the speedo pinion seal and the breather is clear.

Is there any other seals/gasgets I can change?

I don't expect it to be completely leak free, but the triumph anti corrosion system is working too well now!

thanks in advance

 

[johny]

First of all its worth checking the tightness of as many bolts as you can get too cos they tend to slacken off over time. Also the gearbox must have a vent/s (not sure where on that unit) which should be kept clean to stop possible internal pressure build up as the gearbox warms up... 

[Colin Lindsay]

53 minutes ago, sulzerman said:

Hi all 

Got some severe oil leaks on the gearbox and j type overdrive on my saloon, the underside of the car is dripping in oil!

There seemed to be alot of oil around the solenoid, dripping from O/drive sump and off the drain plug on gearbox.

Check the engine sump too. I found that most of the oil round my gearbox was coming from the rear of the sump where the bolts had loosened; as the car drove the oil was being blown backwards over the gearbox.

[sulzerman]

thanks I have some thread sealer which may help too👍 

[thescrapman]

Does the oil smell sulphurous ? 

May be engine oil not gearbox.

 

[Clive]

A friend who fixes boxes has seen a few monster leaks on boxes, a couple of which he built and leaked when the customer fitted them. They have all been down to people releasing a nut on the OD to bot attachment, and fitting a P clip to hold wiring. I think they removed a copper washer or suchlike in the process. 

Not seen it, and was mentioned in passing. But worth a check. I assume it is somewhere near the to of the gearbox/od, and must be a high oil pressure "area". A good clean first and run the car, ideally up on stands (and a stack or 2 of tyres as emergency support) may help locate the issue.

[Pete Lewis]

https://www.canleyclassics.com/?catalogue=triumph-spitfire-mkiv/1500&diagram=triumph-spitfire-mkiv/1500-j-type-overdrive-unit-main-case-brake-ring-and-cam

D type has a copper washer on one of the studs but cant recall or see one for J types

the solenoid has a copper sealing washer and the inside O rings if you unscrew the solenoid youneed a very thin 1" af spanner do not use grips on its case 

theres a good chance you will wreck it,  ( j paddocks sell a spanner )for a few ££

you need to spray brake cleaner to dry off the oil then puff a good coat of french chalk or nice smelling talc powder   this will show a trace of just where the leak is coming from , when its a flood it can be very deceiving

do check all the underside plugs are nipped up 

do the finger test  engine oil goes black   gear oil smells of cats pee    easy !!

Pete

[Pete Lewis]

some good clues on where and how it all works here with a nice pic of the solenoid and its 0 rings 

https://static1.squarespace.com/static/5c6dec53b10f25d4edf0b3f7/t/5c6efe3315fcc083dfc05e62/1550777908670/J+Type+Overdrive+Part+I.pdf

[sulzerman]

Thanks for all the info, it's mainly gear oil leaking. A bit of engine oil too, but not too bad.