Could test the controller with a small 12V DC motor such as an analogue slot car (Scalextric) to see if it's still working to control speed or blown in the course of trying to control the pump.

From what people write on the internet, the pump has some internal electronics such that it runs faster when it senses a pressure increase due to flow resistance (i.e. when you apply torsion to the steering column). If that's the case, then trying to further control the system externally (electrically or mechanically) may be a bit hit or miss.

 

I think if you want to set a constant boost it will work as Keith requires. He wants to be able to reduce boost over the standard too light/boosted feeling.

According to the TRW forums if you delay the "remote" activation one second over the other the pump spins up more quickly if that bothers you.

Agree retest the controller operation although from reading over 200 comments on the device it seems pretty robust & forgiving.

I'm hoping that Keith is able to access and disable the two remotes & connect directly to the motor. Only later models have ECU controlled steering wheel torque and speed sensitivity. The early models are just electric over hydraulic. (got to love the OBD comment "does nothing") I've looked at a number of video installations that seem to run at constant speed.




Seems to me that access is possible.

Not an internal wiring diagram in sight thusfar.

 

I suspect the 'does nothing' is for some testing purpose during manufacture. The remotes should serve to stop the motor if the engine isn't running or the alternator isn't delivering power and possibly to give an extra kick at start up? I don't know how the internal switching (solid state or conventional relay) and control circuits respond to a pulsed (or reduced) voltage supply. To me, it might well work, but I don't think that it's guaranteed. For the moment, it's probably good to check that the PWM system hasn't blown. It's difficult to judge scale from the photo, but those cables look good for more than 60 Amp!

I imagine it's the pump's ability to respond to pressure demand that allows Wilkinson to market their system as 'load sensitive.' It may also increase motor life and avoid the need to cool the hydraulic fluid.

If the PWM doesn't work and there's access to the internal electronics, it may be worth having an electronics guy look at it to see if an internal modif can limit the boost.

 

I was led to believe in my reading that the brown wire connects to the OBD system but I could well be wrong.

I'm hoping the system can be switched in & out by the ignition. It can certainly be cut at the switched control knob although that is less than ideal. Better left at desired setting. As I say in post # 87 above ignition activation would require a fat relay.

Hopefully the controller can be connected direct to the motor & get rid of the "remote" gubbins altogether.

 

There are two (or more) generations of this animal. The first is simple, the second uses the car's 'system.' It may well be that the second takes the brown to OBD. OBD and CAN is great for operation of modern car and makes servicing for many things much easier, but for adapting things to old cars and straightforward DIY it's not kind.

 

Indeed! I was just amused at "does nothing" In this case it certainly does nothing. In the video I was watching this pump was being fitted to make space for a turbo.

Yes there are multiple generations & then they moved to ZF units.

 

Keith. I'm hoping you can gain direct access to the motor electrical connections & bypass the other paraphernalia. The only motor this controller should not work with is a brushless induction motor that needs a Phase change to get it to start.

Before originally recommending that specific controller I checked that the Astra unit was brushed with a conventional commutator & armature.

 

Good Morning All,

I'll be probing the second Astra motor that I have today (other things permitting). You're quite right Glyn, if I can dispense with the two fiendish wires (black and blue/slate) and just end up with a simple positive/negative motor the job could be sorted. At the end of the day at the heart of it all, it's just a motor (at least I hope so - lol !). I'll update later with photos. Even if I eventually ditch the whole project and resort to an original dynamator pump etc it'll help others who may be comtemplating such a conversion. Thank you everyone for your kind advice.

 

Other alternatives are a pressure limiting valve or a flow restricting valve. You wouldn't have the option of adjustment from the driver's seat and I'm not absolutely certain that the electronics in the pump would react well, but it could resolve the high pressure in the steering box while avoiding getting into unknown electrics. The link below is American

https://www.speedwaymotors.com/Heidt...lve,14895.html

A 'restrictor' would be a simple valve and inexpensive.

 

That's what WBO has done or intended doing but it's fixed. Previous owner/friend/engineer had set one up by trial & error to establish ideal orifice size for the feel he wanted. Fortunately the original controller was only $17 if it has to be discarded. That valve is $118. We'll leave shipping out of the equation as it applies to both.

Restrictors can be noisy & raise system temperatures.

However I don't see the fear in tracing the direct motor wiring if it is accessible. It's just a DC motor after all.

We are going over ground that has already been covered. Namely throttling the flow.

 

Glyn, I agree with you throughout. The concerns that I have with powering the motor direct is the effective increase in the duty cycle. It may shorten the life of the motor and raise the temperature of the hydraulic fluid. Ideally, it would be good to swap a component in the pump's internal circuit to reduce the pressure. Strangely TRW provide a lot of info on their mechanical pumps, but not the electrical.
Incidentally, the 118 dollar device in the link is a pressure regulator with a by-pass, so it should be easier to tune than a throttle and have less heating. I agree with you that it's an expensive, unknown quantity.

 

Understood! I doubt these cars are going to do enough mileage for the duty cycle to matter. On the standard generator driven set up you can just Jimmy the pressure relief valve (bypass) in the pump.

 

Hi Everyone,

Firstly let me thank you all for the valuable input you have made - it's really appreciated. This afternoon I examined the spare Vauxhall/GM/Holden pump. Unfortunately the base part is not removeable and so I was unable to gain access to the section containing the circuitry (The base containing the actual motor seems to be thin aluminium and is sealed against the upper casting. Whilst it's possible to unscrew the plastic surround where the five wires enter the upper section and withdraw same slightly that's about it.
I've now made the decision to revert back to an original set-up, using a Dynamator alternator with the take -off for the original pump (managed to locate a pump in the UK - ex military - for £100, which I think is a bargain). I think my main concern with the electric pump option was if it ever broke down rendering the steering extremely heavy. The Wilkinsons conversion, using an XJ6 rack is fine as the rack is obviously engineered to accept the higher pressure generated by the Vauxhall pump (1000 - 1200 psi) but not for the Jaguar Burman steering box.

I'll report back on the forum when the conversion is complete (I have a deadline as the car is booked for my nieces wedding in a couple of months).

Thanks again everyone !!

 

Pity. Good luck. At least you already have all the beefed up bits for PAS.

 

Thanks Glyn,

I've managed to locate all parts now (even a rebuild kit for the pump, just to be on the safe side). The only item that I'm having problems with is the coupling that joins the dynamo and pump (C14936). They are now available new but at an extortionate price. I don't mind fitting a used one (provided it's in good condition) but even they are hard to find. Do any forum members have one knocking around (I'll pay a fair price) or have any leads/suggestions ? Kind regards - Keith

 

Thank you! I've learnt a lot from your experience.

 

See other thread for contact for good used PAS couplings/star drives.

 

LATEST UPDATE .........

I FEEL LIKE SCREAMING !!! My wife has suggested that I give up on the idea of retrofitting power steering and, instead, start going to the gym (when allowed !) to strengthen my arm muscles instead. I thought things were going well as far as accumulating the required parts to finally complete this job. I ordered a Dynamator from a UK company but have now been informed that the box had been labelled incorrectly and they had no stock of negative earth versions of the C42, and wouldn't have a shipment for three months (probably onboard that enormous ship stuck in the Suez canal !). Nobody else has stock of the Dynamators either, and I refuse to pay around £500 for another make (if indeed they were available). So, on to plan B (or is that plan, C, D, E, F, G ????). I've now purchased a used C42 dynamo with the steering pump, which is said to be good (together with a good coupling). So, I'm now going to retrofit a dynamo in place of my current alternator - which will entail refitting and rewiring a regulator unit and possibly changing the dynamo to negative earth. When the Dynamators are back in stock I may then fit one of them - I'll see how the dynamo goes though - if it works OK I may just keep it that way.
Another hiccup occurred yesterday (Phew). The fluid reservoir supplied (used) turns out to not be from a Jaguar at all - it has the wrong cap fitment and the lid bolt is off to one side instead of being central. Hopefully the supplier will be replacing that (fingers crossed).

I love old cars (just sometimes !)

 

Argh! Good luck. You will win in the end.

 

That's awful and becoming too typical. But Solihull is midway between Wolverhampton and Coventry, there must be someone local who could put something together for you. There are still some talented and inventive people around in the West Midlands, though they often aren't very good at advertising themselves.