Irene's rear end

[Rooster]

I knew Irene 1954 Roadmaster was coming Down Under with a noisy rear end.

So I decided this was the first thing I had to fix. Having taken off the housing cover and then pulling out what we Aussies call the spider gears ( the 4 small ones ) I find the following -----

1. The 2 brass curved shims are badly scored and so is the face on the ring carrier.

2. There is far too much ring / pinion backlash estimate

.020 - .025 "

3. Far, far too much axle lateral movement.

One axle estimate .30" +

4. The ring / pinion gears look reasonably good. No chipped or broken teeth. Some wear, but not major I wouldn't think for a 1954 car.

So, some questions for you brothers please.

Where is the growl coming from on acceleration then dies off on de-cceleration.

Where can I get those brass shims from.

Lamar threw in a spare diff centre which I'm pulling down as well. It looks the same but has a ring/pinion ratio of 47/14 ( 3.35) and the original is 41/12 ( 3.41)

Any ideas on which year/model the spare is off ?

Thanks.

Ken ( aka Rooster)

1929 / 25 Tourer

1954 / 76R Riviera Irene.

[old-tank]

The 47/14 (actually 3.36) is late 1955 which will work. Don't mix parts since the pinion bearings on the 1955 unit is one year only. The other bearings and spider gears should be the same. That much lateral movement is probably well worn carrier bearings and/or wear on the axle ends or center block.

Take your best unit and rebuild replacing all of the bearings and seals.

Willie

[Rooster]

Thanks Willie.

Any idea on where to get those brass shims, the curved ones and flat. Were they made available extra thickness. According to the manual the blocks were available oversize to take up excessive axle end float.

Secondly, the smaller spider gears seem to have a lot of up and down movement on the shaft. Is this critical. There is no mention of longer blocks available to take it up. Even with new curved shims I don't think much would be taken up.

Ken.

1929 / 25 Tourer

1954 / 76R Irene

[old-tank]

Ken

It seems that you have too many issues with the current rear and maybe should concentrate on the 55 unit. Record all measurements, take a picture of the current gear pattern and take apart checking all parts for wear, then assemble with a new seal. If the bearings are doubtfull replace with NOS or NORS (made when the cars were contemporary...not Chinese stuff sold by CARS).

The center block is not square...rotate 90* and you should have a thicker dimension. I have some servicible used pinion bearings if needed and new cannot be found; also some spider gears with bushings. The spider gears will normally have a "sloppy" fit and are not contributing to the rear noise since they only turn a little when cornering...compare the 2 rears.

Before a trip I noticed considerable axle movement on one of my cars (no noise or other issues)...thought that I would just have to rotate the center block, but found that there was not excessive movement at the axle ends, rather the whole carrier was moving on worn and pitted bearings.

Willie

[Rooster]

Good advice Willie. I have the 55 diff apart but not yet cleaned up. I hope to have the 54 rear end out and dismantled next week. I'm guessing ?? at this early stage that a previous owner ( not Lamar ) has had the rear end apart and either put old bearings back in or has not set up the gears correctly. With the condition of the teeth , which I would say is reasonably good, the growl must be coming from incorrect mesh. I will blue them up to see contact when I get it out before taking apart.

Thanks for the offer of parts, I will certainly keep that in mind when I re-build. The 55 gears sound promising with the ratio. It will pull the engine RPM down a bit , not a huge amount but with fuel prices these days every little bit helps.

Cheers, Ken.

1929 / 25

1954 / 76R Irene.