Power steering failure

[Ferg]

Since I acquired my 1990 940 td estate it seems the power steering has been a bit temperamental. On first starting the car I can easily turn left but not right. Im not sure but it seems to work after a while (or I just get used to it). I replaced the engine and kept the pump it came with and it made no difference. The new pump to reservoir union leaks a little (a seal will probably sort that) but now the pump is noisy and the steering wobbles on full left lock. What do you think? is there any adjustments i can make or is there something loose, or am I going to fork out even more cash for a new rack. (I should just go the whole hog and get it gold plated!)

[classicracing]

The 7/900 range suffer from what we used to call 'morning stiffness' (known to most men)
This usually occurs on one lock only and in most cases goes away during warm up
There is no alternative I'm afraid but to rebuild or replace the rack.
This is not linked to your noisy pump, the pump delivers simple pressure, the rack directs it to the appropriate side.
Noisy pump is usually caused by over tight belts causing excess load on the nose bearing, if your belt is v tight slacken it slightly, not enough to cause slip but it may 'unload' the bearing a bit and reduce the noise, it may not.
You describe wobble on full lock can you be more specific, cars tend to lose their basic geometry on full lock so will not behave the same as on half lock for example but your word 'wobble' is of concern.
Let me know if this helps
Richard Clark
940 GLE HPT
240 GLT

[ivor940]

Hi, re "Wobble", do you mean that on full lock while stopped, the steering wheel cycles without your input?

ivor940

[Ferg]

I found the fluid has a leak at the pipe union so the wobble has gone after top up (yes, it was a steering wheel 'pulsation' on full lock). Steering geometry is probably is the probable cause as it happened at a tight uphill corner and has not occurred since.
and I kinda thought the steering rack was knacked. I did notice that the steering pump pulley isn't exactly in line with the crankshaft pulley causing a slight lateral misalignment (I am a cunning linguist aren't I) of the belt. Is this acceptable?

P.S Morning Glory? Nice one!

[James_N]

I may as well post here, its as good a topic as any. my 740 PAS is dodgy in the morning but after going round a few corners, its perfectly fine, so im suspecting its the rack? My 740 is due for MOT in May. Do i HAVE to get this issue fixed for the MOT or will it be ok?

[Ferg]

After closer inspection and new 'fan' belts I found the mounting bracket for the PAS pump was bent (yet another injury my engine has sustained from the breakers yard/transport of the replacement engine) at least I've got the old one from the original engine, the new belt has stopped an annoying squeek as well.
Oh, does anyone know the size of copper washer I need for the pump/hose union. I'm scared to even ask Volvo how much the original will be

[ivor940]

Hi, the copper washers are quite cheap from Volvo. You usually need 2 of each size as the Banjo joint has one washer between the bolt and the union, and one between the union and the rack. You can rejuvenate the old ones by tying the copper washers on wire ( not plastic coated) and holding them in a blowtorch or gas plate ( if you have a gas cooker) . Heat the washers to cherry red and let them cool in air. They will be nice and soft to seal the pas joint.

ivor940

[RollingThunder]

The copper washers are typically around the 50p mark each. I seem to have bought loads over the last few weeks and they're all around this figure.

Ivor - I think its about time I bought a blow torch! I could have paid for it by now...

[ivor940]

Hi, The blow torch is also useful to heat ( slightly ) the rear disks when they stick on the hub.

ivor940