Leak on front of Diff............

Author Topic: Leak on front of Diff............  (Read 1364 times)

Offline Glennster

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Leak on front of Diff............
« on: December 26, 2009 - 07:35:52 AM »
 I had my rear end (742 casting) built by Cass aka Dr. Diff, he's a great guy with a reputation for doing good work on rear ends. That said, I'm a little slow to blame him for the leak on the seal of my differential.
  I wonder if it's something I did wrong, the two potential problems that come to mind are:
1. Is it venting properly ( could that cause a leak? )
2. Did I over fill it.

What would usually cause that front seal to leak?
THANKS for any input.




wagesofsin

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Re: Leak on front of Diff............
« Reply #1 on: December 26, 2009 - 07:42:16 AM »
I had my rear end (742 casting) built by Cass aka Dr. Diff, he's a great guy with a reputation for doing good work on rear ends. That said, I'm a little slow to blame him for the leak on the seal of my differential.
  I wonder if it's something I did wrong, the two potential problems that come to mind are:
1. Is it venting properly ( could that cause a leak? )
2. Did I over fill it.

What would usually cause that front seal to leak?
THANKS for any input.


did you check to see if its overfilled?

did you check the vent tube to be sure its clear of obstruction?


Offline thedodgeboys

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Re: Leak on front of Diff............
« Reply #2 on: December 26, 2009 - 07:44:29 AM »
is the fill plug tight?
does the seal look damaged?

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Offline tactransman

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Re: Leak on front of Diff............
« Reply #3 on: December 27, 2009 - 04:38:10 AM »
Did you call Cass??????????
Terry-tactransman 
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Offline Glennster

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Re: Leak on front of Diff............
« Reply #4 on: December 28, 2009 - 06:26:22 AM »
  I'll call Cass today, I was able to get to the car today. I only had time to get it on the lift and check the vent and the fill level. The vent looks OK, it's old and beat up looking, but it's still spring loaded. I did not remove it and blow through it. Maybe I need to do that.
  It is not over filled, I had to stick my finger down almost a 1/2'' to touch fluid....
  We'll see what Cass has to say......

Offline Tonefiend

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Re: Leak on front of Diff............
« Reply #5 on: December 29, 2009 - 04:15:58 AM »
Whats the front?  The pinon seal?  The gasket between the hogs head and the housing?

Offline Glennster

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Re: Leak on front of Diff............
« Reply #6 on: December 29, 2009 - 06:40:37 AM »
  The pinion seal is the leaker. Cass told me to check the seal for damage and make sure the spring is still in the seal. You can't see the spring, but you can take a stiff wire, bend it into a hook shape, then reach into the back of the seal and feel the bumpy or rough surface of the side of the seal spring.
  Everything looks good there......
   Next we took a look at the yoke to see if it's grooved. If the surface of the yoke is messed up (where the seal touches it) that can cause a leak. Mine looks kind of OK. So Cass suggested we try a '' SPEEDY SLEEVE ''. It's a .005'' sleeve that slides over the yoke, this is supposed to give the seal a tighter fit and a better surface to ride on. These things can be a expensive, BUT, lucky for me, Cass says the Car Quest part number 88187 will fit mine because it's the 742 casting/pig. I should have it today, it was only $12. It looks like it will be a while before I can test drive it though, our northern Indiana forecast calls for more snow.....Who knows, maybe some of Al Gore's '' Global Warming '' will drop in and melt the snow tonight, where's that DIPSTICK when I need him!?!?!?

Offline Tonefiend

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Re: Leak on front of Diff............
« Reply #7 on: December 29, 2009 - 12:16:20 PM »
My yoke was grooved and needed a speedy sleeve.   Do you need a special tool for installation?

Offline Glennster

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Re: Leak on front of Diff............
« Reply #8 on: December 29, 2009 - 05:32:17 PM »
 Keep in mind that the 88187 shown here will only work on the pig that is a 742 casting.
  This comes with a tool to put it on...........
  I'm going to lightly sand the yoke, then put it in the freezer to shrink it, I'll put the sleeve in my convection oven and warm it to 200 degrees to expand it. That way it should go on pretty easy, it looks like it will be a very tight fit. I don't want to need a sledge hammer to get it on. I'll also use some RTV to seal it.