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BJ8 Differential Leak

stever

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The differential is seeping fluid at the bottom plug on my BJ8. Would just replacing the plug with a new one seal it up or is there another, better way to seal it? I am wondering if one could effectively use plumber's teflon tape around the threads of the plug? The differential leak is not really significant in fluid loss, but is an irritant. I am fully resolved to accepting the minor oil leaks from the front end of the vehicle, but until recently the differential has never leaked before. Ideas? Thanks! Steve
 
Steve, you can use teflon tape on all pipe fittings (other than brake parts) . Is there a vent on top of diff housing? If so make sure it is not blocked.
 
Hi Steve,

I would use Hylomar gasket sealer (It's sold by Permatex now) to seal the threads. But because it is a tapered plug thread I doubt that is where the leak is originating. Most likely you have a leak around the differential carrier gasket and it is flowing to the lowest point ... the plug. If you find the leaks is from there you need to remove the differential, replace the paper gasket with Hylomar spread thin on all surfaces (gasket, metal and threads).

Cheers,
John
 

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John, I finally found time around all the wife's "honey-do's" to get under the beautiful beast and discovered that the differential leak is actually from the seal around the 'nose' of the differential where it bolts to the drive shaft. Now, I have read the workshop manual on how to replace the seal. It seems to me to be fairly straightfoward and all, but I was wondering if there are any pitfalls to watch out for or 'tricks of the trade' that would help me do the job right the first time. [It seems to me that nothing ever goes right the first time....when I do it]. Thanks, all for any ideas. Stever
 
The first posts are older but I would like to add to the information in them. Teflon tape by adding material to the threads can solve leaking problems. However the real purpose of Teflon tape is to act as a lubricant between dissimalar(sp)metals, works real good with stainless to steal.A very good lubricant and sealer is RTV, not only does it seal good it breaks loose easy un like pipe dope also cleans up better.
 
Steve,
I had that seal replaced by a shop that set up my differential with the 3.54 gears so I haven't done the job myself. Hopefully someone else can chime in with some "tricks of the trade".

Cheers, John
 
I've swapped these seals on other cars (not Healeys), without a lot of "checking" or measurement, and truthfully, I got away with it...but the *correct* method involves "testing for backlash", "bearing crush" and "preload torque"...it can get pretty involved. Here's a site with some info:

https://www.ntahc.org/techtips/REAREND1.html
 

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Steve,

I've done it. It's pretty straightforward. Only hard part is that nut that holds the flange. It's on tight and will take a lot of torque to get it off and back on correctly.

cheers.gif

John, BN4
 
Hello Stever,

One little point, some differentials on older cars use leather seals, which are sometimes supplied. The seal needs to be immersed in oil for 24 hours before installation.

Alec
cheers.gif
 
Thank you all for your comments! I will go to work when the seal arrives.......Incidentally, I forgot to mention in earlier message that I also need to replace the seal in the steering idler. In a much earlier message, I asked a question about steering stability issues and someone asked if I had checked the idler and steering box fluid levels. Well, I did and sure enough the idler was low. After filling, it leaked.....so I need to replace that seal, too. It, too, looks pretty straightfoward - hardest part is to get at the idler to do the work. Any ideas on this would also be appreciated! Thanks, Stever
 
Steve,

Regarding the idler ... I have replaced the seal and bushings. You need to remove the idler from the car .. a benchtop project for sure. You should be able to see if you need to replace the bushings by putting the front end on stands and have someone move the steering wheel while you keep a hand on the idler shaft/pitman arm area. If you feel any movement/slop in the shaft you should install new bushings. The bushings should be reamed to size but you can get away with honing if you have the time and patience. Got to run now but I can elaborate when you get closer to doing the idler.

Cheers, John
 
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