71 240Z. Leaking Diff.

[glassguy]

Last winter I pulled the entire rear suspension out to replace all off the rubber bushings with urethane. Since I had pulled the diff out, I went ahead and cracked the fill and drain plug and refilled it while it was out of the car. It never leaked before this. After everything went back together and I started driving it, it started leaking. I had overfilled it and it was blowing out the top vent. So, with the car in the air and level, I removed the fill cap and about a cup of oil drained out. But, even after that it continued to leak all summer long. Nothing terrible, maybe an occasional dime to nickle spot. So could I have damaged the axle seals by overfilling it, or is it still just blowing out the top. I have it high in the air right now doing a transmission swap, so now might be the time to do something. Any suggestions? 

[cbuczesk]

You need to clean the diff better so we can see where it's leaking. Use some brake cleaner and a rag. Then check it after you drive it. It could be a side seal(s) from the looks of it but it's hard to say for sure. Could be from the vent tube.

 

Chuck

[glassguy]

I'm waiting on the Red Line MT90 fluid I ordered from Amazon to show up so I can complete the Transmission swap that I'm doing right now. But then I have to wait for the snow and salt to go away before I can hit the road and test anything. I think I'll take your advice on the brake cleaner when I can drive this later on, and just let it go for now. 

 

Thanks

[bvolken]

FWIW. My diff wasn't leaking, but I was on the hunt for thumps-and-bumps, so I did the seals in the process. Datsun 240z replacing oil seals r180 differential.

'71 240Z

WoodWorkerB.com

Edited March 7, 2015 by bvolken

[EuroDat]

Can't se much on the photo. You need to clean it as best as possible, take it for a run, get it nice and warm and check it again.

My drain plug was leaking until I used sealant on the threads.

It was probably leaking because I didn't want to over tighten it. They can be a pita to get back out.

Chas

[Travel'n Man]

Overfilling will blow out your seals and your diff will be smoked.............FWIW..........fill to the (bottom) of the top fill plug..........nothing more - nothing less.