De-powering series 3 steering rack

[colingray]

I am toying with the idea of de-powering the steering rack on my series 3 e type.
Has anyone gone down this route to get some proper feel into the car and if so what were the pro's and con's?
I have already added some washers to the pump valve to add weight to the feel of the cars steering but its still very light and lacking any real feel compared to most cars with non PAS or decent power steering.
I know its a big lump up front but it is all alloy so I am hoping it would not be much heavier on the steering than a series 1 or 2 which were non PAS.
I am open to ideas modifying the existing pump if anyone has any proven solutions.

[J44EAG]

I`m not an E-type man in any way but it strikes me a larger pulley on the pump might produce less power assistance....or may be a less powerful pump from another model of the period.

Mike K

[oldtimer]

Hi Collin,
I know my memory is getting feeble but I'm sure every series 1 2 and 3 had power steering. Or the other way around I cannot remember one without power steering. These vehicles used the American Saginaw power steering pump which has an integral reservoir and dipstick. I know for sure the Series 3 E type v12 engine is the same as that used in the Series 1,2 & 3 XJ. Although not an E type owner I am fairly happy that the rack will also be the same as the Saloons.

Examination of the power steering tower attached to the rack , containing the control valves will reveal a torque control rod running down the centre of the unit. I think you will find that the strength of the torque control rod controls the feel or load at the steering wheel.

I just happen to have a control valve on my desk and have decided it would take me for ever to give a proper description of operation, perhaps obtaining an old steering rack and strip it for examination might help.

An option you do have is to isolate the power steering completely. This would entail removing the drive belt and draining ALL the oil from the system to prevent any form of hydraulic lock.
It would be interesting to know just how heavy the steering would be. When folks have had a burst pressure hose but still needed to get home and have needed the arms of a Gorilla, this is because oil is still in the rack.

Good luck but do tell us how you get on

Oldtimer

[raysearles]

Power steering was only available as standard from the Series 3 onward. Having driven a friends Series 2 without power steering - my advice would be don't. In town and when I high degree of input is required like parking you really would notice it not being there, and from a resale perspective you would almost certainly have to refit the power steering since I do not see many buyers viewing the added effort as adding value.

I think Mike is right - there are other routes to gain more feel than go through the need to decouple the existing system. A chat with Ken Jenkins or Colin Ford might prove worthwhile, both acknowledged tech experts for the club on the E Type of all varieties.

In my case I fitted an upgrade from CMC (Classic Motor Cars of Bridgnorth) - that upgrade is designed to provide more weight and feel without requiring biceps of steel to turn the wheel. My rack had no feel and had developed a vague spot at straight on requiring constant correction so a change or rack was required anyway. The CMC upgrade at the time was effectively a FOrd Mondeo rack fitted upside down - I know that is correct because that's how Nick Goldthorp of CMC described it. It has done the trick the wheel turn is progressive has much more feel and weight and it is much easier to understand where the wheels are pointing - it is worth ensuring that the rest of your suspension and steering is properly set up and in good working condition at the same time since any upgrade on a worn out front suspension set up would not fully show the benefits.

Other companies also now offer steering upgrades for the Series III in recognition of what is a known problem with the standard Jaguar power steering so it may be worth checking out those as well.