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

Last September we went on a three day rally with local club members to Collie, a coal mining town in the hills south of Perth WA, about 100 km from home, driving our trusty 29 Plymouth tourer. On the second day we had just finished a circuit round the local speedway track, headed off back to town at 35 mph, checked oil pressure fine at 40 psi, then all of a sudden bang and clatter, clutch in and coasted to halt, engine still running, no oil pressure. No sign of external damage at first, due to bright sun and black engine block, but eventually saw oil where it should not be on outside of block, felt a jagged crack, oh b@#$%^. Local member stopped, we explained problem, and off he went for trailer. So we had lunch on side of road, took Plymouth 100 km back home behind a struggling Valiant 6, DROVE the Plymouth into the shed, then came back in time for dinner celebrations.

It wasnt a good time for this to happen as I had just started stripping Jill's 7 passenger 38 Plymouth for body-off restoration. It is hard to believe how many parts came off it! I have a 5 car bay shed and in desperation had to install a mezzanine floor down one end for the extra bits like seats, windows and running boards. For various reasons the sand blasting of the 38 body and chassis took till Christmas so have only now started on the poor 29.

Basically what happened to the 29 was that the oil pump shaft sheared just below the vanes. The shaft and gear then dropped into the sump and bounced around for a while, knocking a few cracks in the block here and there, in the process bending a rod and punching one bolt 1 cm thru the big end so that the nut was more than loose, and gouging holes in the crank. The camshaft had a few chunks taken out, the gear was damaged and the shaft was bent. The oil pump body was also split. What a mess. I suspect the crack may have been developing for some time, as had been getting some occasional loud noises from oil pump at startup and kept meaning to pull it out and have a look. A warning for you all!

Luckily I have a few spare blocks, so picked one with similar engine number and send it down for cleaning and checking. It looked ok and was 20 thou oversize so ordered new 40 thou pistons and rings from Egge at their Christmas special price. Next was the crank. My best spare crank was too worn so chose to try and recover the original. It didnt appear to be bent, so have cleaned up dings and carefully dressed down a few spots where big end side faces were bulging slightly due to hammering they took. The crank has now gone for crack testing and balancing, together with flywheel and pressure plate, a job I couldnt afford back in 1999 when still had kids at uni. Pistons have arrived and block is being bored. A selection of valves is being refaced. By the way, the exhaust valves were badly pitted. I am going to make sure I use Flashlube additive regularly in future. Luckily I have a spare camshaft in decent shape so dont have to fix the old one.

So now it is back to the 38. First job is to make some stands for the very large and heavy chassis. On the way to sand-blasters we were stopped by police. "What are you doing with a truck chassis on a car trailer" they asked - the back wheels were hanging offf the rear of the trailer - must try and find a 7 passenger trailer!

I have attached a few pics, I hope, as first attempt at this.

The car with bonnet half removed - much easier to take side panels off first, less risk of damage.

The oil pump before removal - no sign of what lies behind

The bent crank and bits of the oil pump

The damaged big end bolt

The damaged pump body

I'll try and add the rest to a second post, suspect I am not doing this right

Where the shaft sheared

Hole 1 outside block

Hole 1 inside

Hole 2 inside

Hole 3 outside

Even after youve cut out all the rust from your panels and replaced it with new metal, there will still be areas you couldnt get to, such as the rolled joint on the front mudguards, folded edges of door panels, back side of welds, rivetted chassis joints, etc.
In 20 years of restoring Plymouths, by far the best product Ive used to provide a stable base for painting is Fertan, a brown sweet smelling liquid that stains fingers permanently black, contains tannins, zinc and phosphate, and stabilises rust. The treated surface will stay rust-free for months, but my advice is to rinse off as recommended then put a moisture resistant layer of paint on it, not just a primer, as soon as practical. My 29 Tourer has been painted for over 10 yrs, is used in all weather and shows no sign of rust in treated areas. It was a basket case when I started. Fertan is widely used by car restorers in Aus and UK, not sure how readily available in USA.
There is some info on www.fertanamerica.com. It isnt cheap (about $50/litre in Aus) so needs to be applied sparingly by small brush, dont end up with half of it on the floor or yourself. It penetrates really well, can be diluted with water if hot weather causes it to dry too quick or you need extra penetration, and needs 24-48 hrs to complete reaction.
It appears you can order thru the USA website, would be interested in knowing if current, prices look cheaper than Aus. In Australia it is made by Chemtech and used to be available at Repco but no more. Chemtech says it is available at Bursons and Mitre10 in Vic, and Coventrys and Mitre10 in WA. It is also advertised by Whitworths Marine. I usually buy 500ml and it lasts several years.

Jim