I got round to filling my solid D axle (modified Mk2) I was dismayed to see a slight leak. The guy who installed my 4.10 Powr-Lok, instead of the open 3.54 he’d chosen, was a pro and I’d assumed he had good technique.
It had not run since building and I figured maybe the bare steel flange seal track had corroded in damp air. I used tissues and cotton buds with carb cleaner but the seal lip area seemed dry although drips were running a few per day slowly from the input seal down to the drain plug. Best I can tell there’s a nick or mark or swarf between seal case and diff casting at about 7 o’clock. Lots of carb cleaner, some ‘right stuff’ black rubber gasket maker in the tiny crack and all is well. I fitted a big breather to keep it that way
Hi Aristides - I wonder if the surface prep on the running surface is part of the issue. I don’t have much experience on this, but a search of the interweb indicates that it’s a thing.
Try searching “elastomer seal running surface finish” or similar to get an idea.
I had a leak at the back of my BW12 - after a professional rebuild. I guess the apprentice fitted the seal. I was a single lip - the type that might come with a kit. A year later I replaced it with a double lip seal and some Hylomar (or similar) at the housing - job done. Paul
Drain the diff, unbolt the driveshaft from the flange and you have access to the pinion nut.
The yoke might be mounted with sealant so an extractor might be needed, mine was not and pulled right out.
Be sure to mark the position of the pinion nut so you can put it back at the same place exactly and not mess the pinion bearings preload.
It was a better and easier job than I expected. About 45 minutes and I had the yoke behind the tranny in my hand. Mindful that everything had been removed in the recent past - no frozen nuts/bolts. The 1 1/2" nut came free with a couple of hits from the rattle gun. Paul
I did drop the rear mounting - maintained the box in place with trusty floor jack. I didn’t upset any if the positioning on the mounting and all went straight back in. Just pulled the forward section of the tailshaft back and to one side, enough access to get the R and R the seal.