Amazon: New (to me) 1963 Volvo 122

[Othen]

Originally Posted by Laird Scooby

The wheel should be further down on the cone in the centre of the balancer Alan - that's why the upper ring has springs on it so the wheel/tyre can be pushed down to centralise it. It's possible to introduce an imbalance if the wheel isn't central - also did you check/adjust the bullseye before adding the wheel to ensure the bubble was central?

Not according to the manufacturer's directions Dave: push the wheel down to centre it on the cone, then the assembly balances on the 3 springs and shafts. I’m just reading it from the book though - I’m no expert.

[Othen]

Originally Posted by Othen

...

I've seen a photo of a second switch attached to the lid somewhere on the internet, and had rather assumed it was probably for the reversing lights, so that may be a good solution - just drill and tap it to M16x2 and fit a second OD switch for the lights.

What I may look at is acquiring a spare M41 top cover and machining both M16x2 threaded holes ready to swap over. That would be a clever solution, but I don't know whether the lid would be easily available...

Alan

This is a note to myself really: I've found a M40 lid (Volvo part #380130) on eBay in the USA. It is $84, but I suppose with shipping and (maybe) duty it will end up costing £100. It might be convenient to have a part already machined and with two interrupter switches mounted when I remove the gearbox, but there would always be a risk of some other issue arising.

I did take the liberty of borrowing a photo of the underside from the ad, and can clearly see the two cast-in guide holes:



... I'm guessing these are just a little less than 16mm wide so as the guide the pilot drill, so that makes me more confident that the 5/8" tapped hole will have enough metal left on the shoulders to re-tap at M16x2, or failing that to fit a helicoil.

On balance I don't think it is worth procuring the spare part from USA - I can get the lid I take off machined, probably the same day, here in Corby.

Apologies - the above was me thinking aloud so that when I forget my line of thought I may remind myself :-).

Alan

[Laird Scooby]

Originally Posted by Othen

Not according to the manufacturer's directions Dave: push the wheel down to centre it on the cone, then the assembly balances on the 3 springs and shafts. I’m just reading it from the book though - I’m no expert.

I suppose the instructions are open to interpretation Alan, also depends on the quality of translation and whether it's into real English or "Chinglish".

Are there only 3 shafts/springs on yours? Fairly sure mine has 4, not that it makes any difference to the operation, just curious.

[142 Guy]

Originally Posted by Othen

This is a note to myself really: I've found a M40 lid (Volvo part #380130) on eBay in the USA. It is $84, but I suppose with shipping and (maybe) duty it will end up costing £100. It might be convenient to have a part already machined and with two interrupter switches mounted when I remove the gearbox, but there would always be a risk of some other issue arising.

I did take the liberty of borrowing a photo of the underside from the ad, and can clearly see the two cast-in guide holes:



... I'm guessing these are just a little less than 16mm wide so as the guide the pilot drill, so that makes me more confident that the 5/8" tapped hole will have enough metal left on the shoulders to re-tap at M16x2, or failing that to fit a helicoil.

On balance I don't think it is worth procuring the spare part from USA - I can get the lid I take off machined, probably the same day, here in Corby.

Apologies - the above was me thinking aloud so that when I forget my line of thought I may remind myself :-).

Alan

Before you get too far along on the add a reverse switch to the lid path, perhaps do a little investigation of the parts books. If your transmission is currently set up for the spring in a tin can mounted on the back side of the transmission the selector rods will not be set up to operate the top mounted switch. As described by Ron K, you would need to find or fabricate the little tab to actuate the switch which is mounted on the reverse selector rod . Some disassembly required!

https://www.volvoforums.org.uk/showthread.php?t=324517

[Laird Scooby]

Slightly "out of the box" idea Alan - why not obtain a lever V3 microswitch and build a bracket so it only operates when the gear lever is in the reverse position and hide it under the gear lever gaiter? Would save a lot of dismantling etc!

[Othen]

Originally Posted by 142 Guy

Before you get too far along on the add a reverse switch to the lid path, perhaps do a little investigation of the parts books. If your transmission is currently set up for the spring in a tin can mounted on the back side of the transmission the selector rods will not be set up to operate the top mounted switch. As described by Ron K, you would need to find or fabricate the little tab to actuate the switch which is mounted on the reverse selector rod . Some disassembly required!

https://www.volvoforums.org.uk/showthread.php?t=324517

That is a really helpful comment, and again shows the value of this forum. It is invaluable to float ideas here first and run the mission rehearsal before lifting a spanner (wrench).

It would seem (from the most erudite Ron K article) that the top mounted switch isn't really worthwhile. Better options would be either the spring in a tin (it should work fine, if a bit flimsy) or (perhaps more likely) a dashboard operated switch with a tell-tale light (like the OD switch I have at the moment - which began life controlling an after market heated rear screen).

Afternote: I've just noticed Dave's suggestion of a mechanically operated microswitch under the gear lever gaiter - that may be worthy of consideration also.

Many thanks - I'll measure 3 times (or perhaps 10) and cut once :-).

Alan

[Othen]

Originally Posted by Othen

Apologies for plagiarising the above... so, thinking about this:

I will have a 4.10:1 rear axle, but with a M41+Type D O/D and the standard Amazon speedometer. The O/D will have a 18 tooth (fine) pinion, but with a 4.10: rear axle (rather than 4.56:1) it should have a 16 tooth pinion like the M40 (as 16/18=0.88 this results in 12% under-gearing of the speedometer compared with the rear wheels).

I think I could use a 16 tooth pinion from a M40 gearbox, but it would appear I'd have to also fit the metal speedometer gear from the rear shaft of the M40 gearbox, and have that gear machined to match the height of the equivalent one in the M41.

I don't have the 16 tooth pinion or the metal speedometer gear from a M40 gearbox, and I'm not inclined to take the O/D apart, get parts machined to fit, replace the O/D, fix all the resulting leaks and so on, so (unless someone knows better) my advice to myself is to leave the everything as it is, enjoy the benefits of the O/D, do a little mental arithmetic and stop worrying about trivia.

:-)

I've brought this post forward as a reminder (to myself) for when I try the silver wheels with the 175/60 tyres (maybe today if the 9 1/2" hub caps arrive with the postie this morn).

The 175/60 tyres will reduce the gear ratio by 7%, but my 122S is over-geared (compared with the way it left the factory) by 12% (hence the speedometer reads 12% slow). The shorter tyres should reduce the speedometer inaccuracy to around 5% (maybe to around zero because the speedo should probably read a little fast under UK law anyway).

I enjoy these little experiments with GAM.

:-)

Afternote: reducing the gearing by 7% might make GAM quite sporty for use around town. It might mean that OD becomes more useful, and so might push me into a more robust solution (than me remembering to turn it off) for the OD inhibitor switch.

[Derek UK]

Reconsider all that you have just written. The car's gearing will be the same as it was. The 4 gears of the M41 are the same as the M40. You are just adding a 5th OD gear. Yes your speedo will be incorrect but you can adjust visually to how the speedo indicates the speed. Your change in tyre size will change both your gearing an how the speed is shown. There is no point in doing that. If you do indeed have an 1800 D OD with the fine gear for the black18 tooth gear I'm not sure what the speedo will show but the 1800 gear can be swapped for an Amazon one. Spend the money on changing that, not on the tyres. I have run an Amazon with a 4.10 axle and OD and it drives fine. You just have to get used to where the pointer is indicating on the speedo.

[Othen]

Originally Posted by Derek UK

Reconsider all that you have just written. The car's gearing will be the same as it was. The 4 gears of the M41 are the same as the M40. You are just adding a 5th OD gear. Yes your speedo will be incorrect but you can adjust visually to how the speedo indicates the speed. Your change in tyre size will change both your gearing an how the speed is shown. There is no point in doing that. If you do indeed have an 1800 D OD with the fine gear for the black18 tooth gear I'm not sure what the speedo will show but the 1800 gear can be swapped for an Amazon one. Spend the money on changing that, not on the tyres. I have run an Amazon with a 4.10 axle and OD and it drives fine. You just have to get used to where the pointer is indicating on the speedo.

I think you must be pulling my leg Derek. Of course changing the rolling diameter (or circumference) will change the overall gearing :-).

My speedometer is measuring how fast the transmission is spinning... that is all.

You meant this as a joke... right?

:-) Alan

[Derek UK]

It was to make you think. It's much cheaper to live with the speedo error and get so your brain tells you whether you are speeding or not. At this point I don't think you really know what the error is under road conditions?
As has been mentioned if you have no inhibitor switch and select reverse and drive backwards with the OD engaged you will wreck the box and/or the OD.