Leaky Leaky

[Damien8086]

Thanks for the quick reply Dennis. I’ll try cleaning the area up as recommended. I wiped it down a bit with a rag and it definitely seems to be coming from where the axle goes into the differential on the passenger side, but I’ll get some engine cleaner and try and confirm.

[RexJohnson]

It could also be coming out of the adjuster o-ring at the axle seal. After clean look real close to see how high up the leak starts.

[joelsplace]

If you need to change the o-rings buy the tool Rex sells. Makes the job easy compared to almost impossible.

[Damien8086]

Stuck a piece of cardboard under it last night to get a better idea of how much it is leaking- seems to be quite a bit.

[Frank DuVal]

If that is one night's drips, then yep, time to replace some seals.

Early is easy, just take 4 nuts off wheel bearing flange, slide axle assembly out as far as it will come, then replace the side seals (seals the yokes to the differential). Then replace the shifter seal. Hint, if that seal has no flange (the originals did) run a sheet metal/sheetrock screw into the steel part and pull the seal out. When installing the shifter seal make sure the holes for the coupler pin are smooth, a rough edge will tear the new seal. Or put a wrap of tape over the holes..

On the old site (CCF) there was a list of National Part Numbers for these seals. All the Corvair vendors carry them too.

The back up lamp switch is on the transmission, but the wires go into the tunnel a few feet to connect to the body harness.

[Damien8086]

If that is one night's drips, then yep, time to replace some seals.

Early is easy, just take 4 nuts off wheel bearing flange, slide axle assembly out as far as it will come, then replace the side seals (seals the yokes to the differential). Then replace the shifter seal. Hint, if that seal has no flange (the originals did) run a sheet metal/sheetrock screw into the steel part and pull the seal out. When installing the shifter seal make sure the holes for the coupler pin are smooth, a rough edge will tear the new seal. Or put a wrap of tape over the holes..

On the old site (CCF) there was a list of National Part Numbers for these seals. All the Corvair vendors carry them too.

The back up lamp switch is on the transmission, but the wires go into the tunnel a few feet to connect to the body harness.

Thank you for the info, Frank. Are there any videos online for this job do you know? Before starting should I drain the fluid and if so then is the drain bolt the one in this first picture? And the bolt in the middle of the red circle is the refill hole? Thank you!

[Frank DuVal]

Both of those are fill/check holes, the red one being the four speed transmission.

The drain plugs are at the bottom and face rearward (transmission) and forward (differential). If the transmission does not have a drain plug then unscrew the back up lamp switch.

See 1961 shop manual here:

https://www.corvair.org/chapters/corvan ... anuals.php

But also buy a printed one for better pictures when you can.

[Damien8086]

Both of those are fill/check holes, the red one being the four speed transmission.

The drain plugs are at the bottom and face rearward (transmission) and forward (differential). If the transmission does not have a drain plug then unscrew the back up lamp switch.

See 1961 shop manual here:

https://www.corvair.org/chapters/corvan ... anuals.php

But also buy a printed one for better pictures when you can.

This is a 61 body, but a 64 transmission - still the same? I have the manuals but still getting used to finding what I am looking for in them. They are a little bit difficult to comprehend at times for someone new to all of this.

[jimbrandberg]

I don't know if it's leaking from the differential side seals or not.
If so, Early differentials can suffer from a malady I like to call yoke slop where the radial play of the yoke inside the differential is excessive to the point where the side seal can't contain the oil. With the car jacked up you can grasp the axle to see how much the yoke moves around in the differential perpendicular to the axle length.
Truly fixing it is a big job.
Running the gear oil level down from Full helps somewhat and it will sometimes leak a lot down to that level and then just a little. A '64 with a dipstick is a tremendous help to monitor the level. If the differential is full to the point where the oil runs out of the fill plug hole, it's easy to see how oil can come out of a side seal.
I've never taken apart a differential in order to have a sleeve made but that day is coming. Ken Hand knows how to do it.

Again, I don't know if this is your problem, I just present it as one possibility. I couldn't tell much by the previous pictures and don't know if the leak has been traced upwards from the initial spot on the floor. I use a plumb bob.

If you can watch a dipstick to keep it at Add rather than Full it doesn't get much easier than that. Some folks with a lot of patience can get oil in there through the dipstick tube, maybe some sort of a drip arrangement where you can walk away...

This is just my opinion and I'd like to read more about it. Perhaps someone has a more correct term than "yoke slop".

Jim Brandberg
Isanti, MN
Corvair Repair.com