Seeing as I have the 29 Plymouth in pieces with engine half rebuilt, I decided to do a couple of jobs that have been on the to do list, namely the gearbox rear seal and the diff pinion seal. I originally replaced them in 1979 and they sat for over ten years before hitting the road, so I guess they have given good service.
NOTE I HAVE EDITED THIS PARAGRAPH!! The gearbox seal was simple .. off the shelf neoprene seal, but not so simple as I first thought! Its a metric size 38*62*7 mm, not imperial. I should have realised, as I do remember that the gearbox bearings were hard to find in 1979 until I realised they are metric. Seems strange for a car made in USA but my bearing man tells me it is quite common??
The diff seal is a large composite riveted unit which is still available at a price, but it is much cheaper to rebuild it. First drill out the six rivets with a 5/32 inch drill. Disassemble and clean, keeping only the outer housing and the seal retaining plate. Purchase a neoprene seal ID 1-9/16 inch, OD 2-1/4 inch, thickness 3/8 inch. Cut a 1/8 inch thick neoprene cork gasket spacer to hold the seal central in the housing. Put a thin layer of silicone sealant on the inside face of the housing, then place the cork seal in the housing with the neoprene seal located centrally inside it, put another layer of silicone on the cork, then place the retaining plate over the neoprene seal. Pop-rivet the assembly using 5/32 inch rivets, and wipe off excess silicone, then leave 24 hr to cure. Give it a coat of gloss black and it will look like a bought one.
The four pics below show firstly the four pieces to be assembled, then cork inserted, then seal inserted, and finally retainer put in place.
Happy motoring!
Jim
NOTE I HAVE EDITED THIS PARAGRAPH!! The gearbox seal was simple .. off the shelf neoprene seal, but not so simple as I first thought! Its a metric size 38*62*7 mm, not imperial. I should have realised, as I do remember that the gearbox bearings were hard to find in 1979 until I realised they are metric. Seems strange for a car made in USA but my bearing man tells me it is quite common??
The diff seal is a large composite riveted unit which is still available at a price, but it is much cheaper to rebuild it. First drill out the six rivets with a 5/32 inch drill. Disassemble and clean, keeping only the outer housing and the seal retaining plate. Purchase a neoprene seal ID 1-9/16 inch, OD 2-1/4 inch, thickness 3/8 inch. Cut a 1/8 inch thick neoprene cork gasket spacer to hold the seal central in the housing. Put a thin layer of silicone sealant on the inside face of the housing, then place the cork seal in the housing with the neoprene seal located centrally inside it, put another layer of silicone on the cork, then place the retaining plate over the neoprene seal. Pop-rivet the assembly using 5/32 inch rivets, and wipe off excess silicone, then leave 24 hr to cure. Give it a coat of gloss black and it will look like a bought one.
The four pics below show firstly the four pieces to be assembled, then cork inserted, then seal inserted, and finally retainer put in place.
Happy motoring!
Jim