1800: Reviving a Saint. 1 UNDERCARRIAGE

[chirlas]

REAR AXLE AND PROPSHAFT
Brushing, cleaning and painting are easy tasks and pay encouraging dividends.

The diff is clearly marked as a 30 model and a metal label (not in the attached picture) states the relation is 41:9 or 4:56. Next step will be checking backlash and crown/pinion teeth patterns, a complete unknown territory for me. VP Autoparts sells an unexpensive marking compound for checking the patterns.

Propshaft is a 44,5mm Hardy Spicer. The UJs seem to have no play, but the central bearing has a little. The plan is to change the three UJs and the central bearing.

About the axles, I have been said that the bearings are rock solid but I tend to think that trusting on them would be a false economy. They are supposedly just 70k km/44k miles old, but I am not able to test their condition. Do you think todays Timken bearings are on par with the period ones?

And a last question: you can see in picture 1057 a plate welded to the propshaft that reads "2/3". What is that?

[grumpydad]

Hi
the plate welded to the prop is for balance
to stop vibration

hope that helps

[Derek UK]

If the mileage is correct I'd not touch the diff or the wheel bearings. Flush the diff and refill. Possibly grease the wheel bearings if you can. Replace the clearance shims as you found them. Centre bearing, change along with the mounting rubber. U/J's, your choice. Make sure the 2 prop pieces are joined back up correctly.

[chirlas]

Derek, I am not able to measure the shims. Both are stuck to spacer washer PN 673789. This part is not available and I am afraid to break it if a try to liberate the shim. Keep it untouched as with the bearings?

[Derek UK]

Shim/shims would probably come off it soaked in penetrant but yes just clean things up and leave them. Spacer 673789 is apparently 4mm thick. 673789 is the gasket. These shims space out the half shaft clearance. There is a thick one on one side that you don't touch and the clearance is then set on the other side via shim thickness selection. These rarely need adjusting except after a major axle overhaul.
Don't try and clamp things up with the oil seat plate bolts if it's all hard to fit. The plate will bend/distort. If you aren't taking the bearings out it all should go together OK.

[chirlas]

I am afraid these are not shims, but spacers. 5mm thick. So the axle has not shims at all. Bearings are 1,7mm proud on right side, 0mm on left. Will I need shims?

[Derek UK]

Read the manual re shimming the axle. Check the shims here.
https://www.classicvolvoparts.co.uk/...ings_and_Seals

It's normal to use a selection to get the correct play. Best to use as few as possible rather than a collection of thin ones.

[chirlas]

Brief summary after living under the car for a while:
- Anti gravel brushed off (not peeled off). Nasty job. Dinitrol Rust Converter plus paint applied where surface rust popped up. My theory says that what does not come off after an energetic wire brush massage does not have rust inside
- 1 kilo of beach sand extracted from behind the C points. Dyson vacuum cleaner with a hose attached proved to be a good tool. the car lived in Mallorca before
- Very good right rocker panels and sills with traces of a nice welded repair
- Good left rocker and sill. RConverter+zinc paint spray injected. Thinking of injecting wax later
- Sound deadening painfully stripped from floors. RConverter and zinc over minor areas of surface rust. Then 2 coats of white primer
- And now the high tech touch: japanese thermal insulation paint used in rockets called Gaina. 2 coats over the primer. An additional pair of 91 Yellow paint will be added. Not sure if carpets will fit on top of this sandwich

Enclosed pictures to illustrate the action

[chirlas]

Front axle parts were already blasted when I bought the abandoned project, but rear axle was perfectly preserved in its grime. Bought a desktop sand blasting cabinet for 250€ and here you have the results. Please, pay attention to the state of the art vacuum system added by myself.

[Derek UK]

Some sort of filter and deflector inside your blaster would much reduce the amount of abrasive going through your vac cleaner. The abrasive will soon wreck it.