940 Alignment

[arctan]

Thanks Luke and Dave. I think I'll start with just balancing, followed by the ball joint, and probably spaceship poly bushes at the same time. And look in to alignment strategies later.What a delight it must be to have good steering! And I do appreciate the idea of having the gear vs paying out for a questionable result. In my earlier careers (sound engineering and network management) I was quite in to test and measurement. In the meantime there is a list of to do's that I have to prioritise, and sort over the next few months. So, thanks again, and best of luck with your lovely Volvos.

[Rversteeg]

Wheel wobble somtimes developes when the tyres wear. When there is an front wheel unbalance at both sides, with constant speed you sometimes feel the vibration in the steering wheel come and go in long motorway bends. As the wheels rotate at slightly different speed the relative position of the unbalance OS/NS changes, causing the vibration to even out and to reinforce.
Just have your wheels balanced as a first action. I suggest not to go to one of the national tyre discounters but to a local workshop. I took mine to a local tyre shop and was surprised that he first checked the unbalance before taking off the balacing weights (the KwikFit guys take off the weight before even starting, so you can't complain afterwards that the balacing was not necessary...). When he later used a manual torque wrench on the wheel nuts I knew where I am going next time.
The balancing cured my steering wheel vibration, but did nothing to the vibration while braking.

[arctan]

Can anyone see the part number for Volvo spaceship bushes, please. Just doing a 'compared with poly' ...

[Ian21401]

[QUOTE=Rversteeg;2550465,
The balancing cured my steering wheel vibration, but did nothing to the vibration while braking.[/QUOTE]

That could be caused by a faulty brake disc. Just replaced the front discs on my daughter’s XC70. She reported vibration through the pedal and steering wheel when breaking normally. Check revealed a “high spot” on FOS disc. Changed both discs and pads. No more vibration.

Ian.

[Rversteeg]

I had the discs changed last year, so that could be the case. I had the same problem with the previous disc change, but I had those skimmed. It cured the vibrations for a short while, but when they came back I had them changed for OEM discs (whatever those might have been). No more problems since.
Before changing the current discs again I am going to try the bedding-in method described here (https://alconkits.com/support/brake-...d-brake-rotors) will do any good.
I understood that the 940 front wheel set-up is quite sensitive to braking vibrations, just as the Opel/Vauxhall Omega was. But in the Omega case time has solved this, as there are hardly any around anymore...

[arctan]

Just to say I had the fronts balanced, and the slight (but worrying) downhill wobble has gone.
(Cheaper than discs then!).
Having been focusing on the front end, I can now feel that it is less than perfect, so I will get the advisory 'slight left lower front ball joint play' attended to, then do the bushes- probably both ends of the bar. Maybe Poly for the spaceship and rubber for the body end? And I might buy the alignment kit, and deploy it in conjunction with my friendly Volvo restorer. I'll need to make some 'swivel plates'...
Thanks as always to everyone for their input!
PS: to save me asking later, can anyone suggest the toe in values for 16 inch wheels please?

[Laird Scooby]

Originally Posted by arctan

Just to say I had the fronts balanced, and the slight (but worrying) downhill wobble has gone.
(Cheaper than discs then!).
Having been focusing on the front end, I can now feel that it is less than perfect, so I will get the advisory 'slight left lower front ball joint play' attended to, then do the bushes- probably both ends of the bar. Maybe Poly for the spaceship and rubber for the body end? And I might buy the alignment kit, and deploy it in conjunction with my friendly Volvo restorer. I'll need to make some 'swivel plates'...
Thanks as always to everyone for their input!
PS: to save me asking later, can anyone suggest the toe in values for 16 inch wheels please?

The big thing to remember John is when working with suspension, brakes, steering etc, what you do to one side, you must do to the other. In other words, if you renew bushes one side, you need to do the bushes the other side. It can throw things out of balance such as braking effort if you don't - this is particularly true with things like brake pads and shock absorbers.

As for the wheel alignment settings, the degrees, minutes and seconds is 0d, 18' 0" +/- 8' toe-in which should cover all wheel sizes.

[arctan]

Many thanks for the settings Dave. And I'll definitely be doing the bushes on both sides for the sake of completeness, and balance!