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Common causes of Differential Seal leak?

karls59tr

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Common causes of Differential Seal leak?

is there a typical reason for a leaking diff seal on a TR3 other than overfilling?
 
Re: Common causes of Differential Seal leak?

Grit gets embedded in the original leather seal, and cuts a groove into the surface of the input flange (where the seal rides). This can make new seals start leaking immediately. If you can't readily polish the surface until no mark is visible, it's Speedi-Sleeve time.

But check the vent first. I've never had a problem with it, but it's sure a lot easier to check than the input flange.
 
Re: Common causes of Differential Seal leak?

Willie_P said:
clogged vent causes back pressure

I agree! Rebuilt mine last year and put a cap on the vent to keep dirt from getting in. When I was finally ready to drive a year later, the brand new seal was seeping. At first I thought I screwed up the rebuild, but then I checked the oil level and the oil came shooting out. It finally occured to me that the plug was in place...removed it and the level dropped and leak ended.

That pressure was just from the temperature changes from the cold weather when I had added the fluid and capped the vent last winter. I know that when I bought the car the vent was also totally clogged by grunge.

_DSC4576.jpg


You can see the cap in this photo:

_DSC5786.jpg



Lesson learned about temp changes and the need for vents!

John
 
Re: Common causes of Differential Seal leak?

Sorry.... I don't see the cap in your photo.
 
Re: Common causes of Differential Seal leak?

LexTR3 said:
Sorry.... I don't see the cap in your photo.

Here:

Cap.jpg


But the point is - don't do that (and assure that little pipe sticking up is not clogged). A bent wire inserted into it is how I check -- use a wire long enough there is no chance of losing it in there.
 
Re: Common causes of Differential Seal leak?

Has anyone tried using one of the higher tech vents, that help block dirt from getting in?

9833k11p1l.gif
 
Re: Common causes of Differential Seal leak?

I'm interested...where did you find that one?

John
 
Re: Common causes of Differential Seal leak?

TR3driver said:
Has anyone tried using one of the higher tech vents, that help block dirt from getting in?

9833k11p1l.gif

We use those for pneumatic valve exhaust port mufflers at work. They should work fine as a vent. Air flow capacity is high, but that stone filter, or whatever it is, can and will plug up with dirt. That's when the cylinders start moving very slow.
grin.gif
 
Re: Common causes of Differential Seal leak?

I tried one in the OD, but it seemed like it leaked more than the original. Didn't particularly investigate, but I'm guessing that the gears threw a layer of oil onto the inside of the filter, which then got pushed through when the air warmed up and escaped through the filter.

But I could have been mistaken; or the same thing might not happen with the diff.

Just seems like a lot of dirt would fall in that open hole in the original breather. I guess it's not important if you follow the factory recommended change interval, but I have a bad tendency to let it go a lot longer than 6000 miles.
 
Re: Common causes of Differential Seal leak?

I just always put a length of vinyl tubing on the vent, curl it over to the axle and clip it there, and then let it dangle a few inches below the axle. The movement of the free end of the tube keeps the dirt cleaned out.
 
Re: Common causes of Differential Seal leak?

TR3driver said:
I tried one in the OD, but it seemed like it leaked more than the original...

[hijack] Where is the vent on an OD? [/hijack off]

The addition of a tube sounds reasonable, or a clever fellow could make a little 'hat' for the tube (like I have on my chimney).
 
Re: Common causes of Differential Seal leak?

bgbassplyr said:
I just always put a length of vinyl tubing on the vent, curl it over to the axle and clip it there, and then let it dangle a few inches below the axle.
Good idea, thanks!

Geo, here's a shot of the "40 micron" breather vent installed in place of the original OD vent.

DSCF0049.jpg
 
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