Transmission rear seal leak

[kunzma]

I had my engine and transmission out of my Jan/1971 240Z for its restoration.  While I had them out I changed the seals on the transmission.  Afterwards, I still had a leak at the rear seal and went to a local shop to have professional install one in case I did something wrong.  Weeks later it is still leaking.  Anyone have some experience with this seal?  Is there a technique I missed?  Is it just two bad seals in a row?

Edited September 30, 2019 by kunzma

[Dave WM]

a couple things, 1st are you 100% sure its the rear seal and not dripping from the top of the shifter?  there will often be a lot of oil getting up there (should be NONE) that eventually finds its way to the rear part of the trans and then drips down. You can tell by pulling the rubber gator off the top of the shifter and see if its all gooey with oil.

Second IF it is for sure the rear trans seal, you may have a badly worn bush allowing too much play in the drive shaft. see if there is side play right up at the joint where the drive shaft sticks into the trans. IF so then you should replace the bronze bush.

[kunzma]

Thanks for the quick reply Dave WM.

Pretty sure the leak is at the rear seal.  I'l get under there tomorrow and check the side to side play in the drive shaft.

[Zed Head]

2 hours ago, kunzma said:

I had my engine and transmission out of my Jan/1971 240Z for its restoration.  While I had them out I changed the seals on the transmission.  Afterwards, I still had a leak at the rear seal and went to a local shop to have professional install one in case I did something wrong.  Weeks later it is still leaking.  Anyone have some experience with this seal?  Is there a technique I missed?  Is it just two bad seals in a row?

If the old seal rubber wore through to the wire spring there might be a groove in the slip yoke.  Not uncommon. 

[grannyknot]

7 hours ago, Zed Head said:

If the old seal rubber wore through to the wire spring there might be a groove in the slip yoke.  Not uncommon. 

And if that is the case the cheapest way to remedy that is to install the new seal a little farther in or out from the  stock position, only talking about a 1/16", just enough so the lip of the seal doesn't run in the groove.

[kunzma]

Many thanks!   I'll give those suggestions a shot tomorrow.