On my 2wd 24v BOA sapph, which has full cosworth 2wd suspension and steering, the steering is much heavier than on my 4x4 YB sapph, even though the 4x4 runs wider tyres. I don't really like the steering on the 2wd, it's just too heavy. Is it common for the 2wd to have heavier steering/less assistance than the 4x4? Since the engine on the 2wd is the BOA, I run the PAS pump from the BOA, but I wouldn't expect that to make a difference compared to the YB PAS pump.

Earlier I had a standard (non cosworth) steering rack on the 2wd. But that steering rack had too much lock in combination with the 3dr cosworth hubs, making the wheels rub on full lock. At the same time I changed the PAS pump from a later (speed dependent type) to the earlier (non speed dependent type), because the speed dependent type runs higher pressure which I believe made my steering rack leak past the seals. Using the earlier setup (non cosworth rack and different pump) the steering was much lighter.

So is this how the 2wd steering rack should feel? Or is the rack not OK, or maybe the pump doesn't make enough pressure?

 

it should be light enough to turn with one hand

but most of my cars have been the 4wd variety so it might mean that they've got higher rated pumps to move more stuff around

 

Mine's very light

 

I believe yours is a 4x4 as well? My 4x4 is fine, indeed light enough to turn it with one hand. The 2wd you really can't turn it with one hand.

Any people with experience of both 2wd and 4x4, whether the 2wd steering is supposed to be heavier?

 

Mines 2WD and not a hope could I turn it with one hand. Loosened the PAS belt and it is indeed lighter now...still a push to turn with one hand but can be done. Interesting thread for me as would like to have my PAS spot on. Always thought it was crap since I've owned the car Power assisted steering my arse!!

 

Hmm, another 2wd that's heavy.

BTW, I can't really see how loosening the PAS belt would make the steering lighter. If the belt was too tight I guess it would wear out the belt and perhaps the pump bearings due to the extra load. But I can't see it making a difference to how the steering feels, as the pump should still do the same pressure.

 

I know what you mean Marc but after loosening it, it feels better!

 

Think I'll go for one of these in the future as seals are probably worn in mine:

http://shop.grahamgoode.com/power-st...04-67474-p.asp

Philip.

 

Hi lads mine is nowhere near as light as most cars out there nowadays but can turn it with 1 hand ok

 

Yes mines an early 4wd so the pump is the same as the 2wd.

It's only the rack what differs

 

All 3 of the 2wd cossies i have the steering has been heavy. But noticed on 4x4 and escorts its lighter.

Maybe you can modify the pressure release valve in the pump? If it has one?

 

Hmm, maybe better to use a steering rack from a standard 2wd Sierra. The only problem is that it has too much lock for the Cosworth suspension and makes the wheels rub on the inner arch (MoT failure). But perhaps that can be solved using lockstops?

 

Bringing this thread back from the dead since I finally have the car running again after a full re-shell. Since all the hardware has been transferred to the new car the issue is still there but it is actually worse now. At some point (maybe only when the engine (or steering oil) is cold there is a judder through the steering when turning the steering wheel. And besides that it is still very heavy without much feel in the steering, perhaps even more than it was several years ago.

So I've been reading up on how power steering works and it is actually not that difficult. This video gives a very good explanation:
But it makes me wonder why the amount of assistance would be different between the different versions of the Sierra (Cosworth). As far as I know all steering racks have the same internal dimensions for the piston, so with the same pressure from the pump they should have the same amount of assistance. I guess there must be something wrong with either my steering rack or the pump. It's just a shame I have to use a 2wd Cosworth rack because I have too much lock with a regular Sierra rack. It seems the lock stop on the passenger side might be exchangeable since you can removed it to remove the actual rack from the housing. But I think on the driver side the lock stop is just part of the housing.

 

Hi Marc, I changed the power steering rack and power steering pump on my 2wd Saff a few years back and I was very suprised at the difference it made. Much lighter than it was before with a nice direct feel to the steering. I had got used to how it felt for over 20 years so for me it was a very good upgrade!! I run mine with lowered suspension, Hi-Spec big brake conversion,17inch ET35 alloys with 215/40/17 tyres. Have you fitted a new/reconditioned power steering rack or pump to yours as the problems you are having to me seem to point to one or both items having a fault?

 

It seems indeed that either the pump or the steering rack (or both) is faulty. I will try a DOHC steering rack that I still have lying around. In the past the steering was a lot better using a DOHC steering rack, but on full lock the tyres hit the chassis rail which is an MOT failure, so that's why I fitted the cossie rack. But I found a company online that makes steering lock stops for the Sierra, so with those I should be able to use the DOHC rack again. But the car is off the road for the winter, so when the temperatures go up I will have a try if the DOHC rack solves the problem.

 

Sounds like you may have come up with a way to sort it out, good luck!

 

I used this pump on mine, higher pressure than standard. Works well…

https://www.ebay.co.uk/itm/Power-Ste...-127635-2958-0

 

Thanks! Nice to know that pumps from other car manufacturers fit too. But I suppose you mean for a YB? Although it does look like the one on my BOA too.

 

i no this is an old thread ive got the same issue 2wd saff power steering seems heavier than it should be, the link to the pump you added in your post doesnt work anymore. would you mind telling me what pump you used one of the bmw pumps spring to mind thanks

 

 

ideal thanks for the reply thats a great help. do you no anyone that has used one of these and did it make any difference thanks once again

 

Anyone know what pressure the standard Cosworth pump is meant to put out?

I'm using a Cossie rack with a Peugeot 206 pump (100 bar from what I can find out) on my mongrel Sierra and the steering is very heavy

 

I have no clue on what pressure the Cosworth pump should do. But 100 bar doesn't seem low to me. I know that my BMW 130i has a pump that does 120 bar and that car is a bit heavier than a Sierra and runs a lot more castor, so that makes the steering heavier. But apparently running with 120 bar is no problem in that case.

I guess your problem might be the steering rack and not the pump. It seems that quite some people have heavy steering on 2wd Cosworths, so I'm guessing the torsion bar in the steering rack is just stiffer than the one on the 4x4, or the one on a normal 2wd Sierra rack. I now use a normal 2wd Sierra rack with custom made lock stops and it steers a lot easier than it did with the Cosworth rack. But I do believe there might have been something wrong with my Cosworth rack.

 

I'm thinking the Peugeot pump has the pressure but not enough volume, the steering gets heavier the faster I try to steer it!

Anyone on here tried the BMW pump?