I have a 1967 800 with the 4 cyl 196 and I am replacing the clutch. I have had a leak dripping from the flywheel cover. I believe it is gear oil from the tranny. I have the wheels blocked up so I have a little more room to work underneath. The scout is slanted back a little due to the driveway. I have the center cover and rear driveshaft removed. When I start it and let it run I do not see any leaks at all, even after it is shut down. I expect that the rear main seal is NOT leaking and perhaps the tranny input shaft is not leaking because the scout is slanted back a little. When I pull the tranny I am thinking of replacing the front main shaft bearing with a sealed bearing and double checking that the input shaft seal is good. I don't want to replace the engine rear main seal if I don't have to. Is there a way to prove the T90 is leaking out the input shaft when I get it out. If I could check the oil on the floor for engine or gear oil I would , but none to check now. Any thoughts, THX
Leaking T90 I Think
- Thread starter Bigblue1
- Start date
Robert Kenney
Super Moderator
If it smells skunky, it's gear oil, if it is smoky and dark it's likely engine oil. It is uncommon for the input shaft to leak. Some transmissions don't even use a seal there, just a drain back channel.
However the main seal is a common leak location.
However the main seal is a common leak location.
Found the problem. The last shop that worked on my T90 many years ago had a front bearing retainer with a neoprene seal that was for a 1" shaft diameter at the seal location. I have a 15/16 shaft. Also, the T90 steel keeper for the shafts was installed with the tabs on the bottom instead of the top and they were holding out the transfer case by about a 1/16" and so it was leaking between the T90 and the transfer case. Got a new bearing retainer with a seal for 15/16" shaft, installed the keeper correctly, and re-gasketed everything.
