Sewer Cap

[utahseries]

All the purists will not be too happy with this.. My differential housings are almost completely rotted through, so I decided to weld on some sewer caps instead. What sizes should I use? And where can I find them?

[HybridIIA]

This should work... http://www.mcmaster.com/#43425k246/=3retpl

[alaskajosh]

That's the one alright (McM-C link). A little steep though.
Even in Alaska, and with the shop having to special order it, I got mine for right around $30.

You'll need to visit the most industrial shop you can find... the one that the municipality and big commercial contractors go to. Your local Ace Hardware is not going to have a clue obviously.

There's a great step-by-step on pirate4x4 but I can't find it right now.

Did find this:

http://www.pangolin4x4.com/pangolin4x4/projects/ultimateaxle/capwelded.jpg

Cut about 5/8"-3/4" off the base so it doesn't stick out too proud and foul your tie-rods. Be aware of ring gear clearance. You may need to make cuts, bend out of clearance channel on the edges, and weld.
I was able to reuse the fill plug out of my old, stock, diff cover.
The last remaining challenge was cleaning the gear oil off well enough for good welds... I used brake cleaner and then struck an arc.... don't do that. I had a WHOOSH of flames up to the ceiling!!

Kind regards, Josh

[KevinNY]

If your axle housing is so rusted that you are about to loose the pans then it is unlikely that you will get satisfactory welds that will hold oil. To do it right you need to remove the housing, grind like a madman, and torch the oil out of the steel before attempting to weld one on.

[pisten-bully]

My differential housings are almost completely rotted through, so I decided to weld on some sewer caps instead.

Here's the "right" part... but maybe you knew that! We've used them before and they weld right up once you grind the rust off the banjo. Ours don't leak.

http://www.steveparkers.com/proddetail.php?prod=SPCK210