Variable control for Saxo power steering pump

[gpny]

Hello all, this is my first post on this forum and I hope you will be able to help me.
I did search without finding an answer. If it has already been posted, I'm sorry, and would appreciate a link to the previous discussions.

I am trying to fit an Electric Citroen Saxo power steering pump to my Honda Civic in the U.S. The reason I wan't the electric pump is that I do not have the space for the factory mechanical pump on my civic's turbocharged motor and I would like to be able to vary or turn off the assist depending on the drivng conditions. On the highway, I would prefer no assist, and when racing or in the city, I would like some assist.

That said, does anyone here know how I could go about varying the pump speed? Has it already been done? If so, what components were used?
Next, when the pump is off, does it leave more resistance than what there would be with a looped rack? (IE does the pump block fluid movement and add fluid resistance when off? - If so, would adding a high pressure vessel help reduce the problem by creating more volume in the feed line?)
Finally, does anyone know where I could get the factory power steering hydraulic and electrical system diagrams so that I could study the components?

Thank you very much for any insight?

[djrem]

wrong section.

Welcome aboard though buddy.

try posting in the newbie section to say hi!

[gpny]

Sorry about the wrong section. Which section should this be posted in? I will start another thread there. I didn't think this was a newbie section post. It's more of a technical post.

[Scott]

Hi gpny,

I have moved this to engines/performance, which may seem bizarre but those with most knowledge frequent the section.

Ill have a look later I have to run at work now

[gpny]

great. Thanks Scott, I look forward to it.

Maybe I should post in the Newb forum, but here's a little more about myself:
My 'toy' is a 1994 honda civic Dx Coupe. It is a never ending project and i've done the following upgrades to it:
Engine:
D16Y8 block (1.6L bored to 1.68l)
Darton Sleeves
JE Race 10:1 Comp 2mm over pistons
AEM Rods
Ported/Polished head
Home Made turbo setup with Mitsubishi/Hahn Racecraft Super16G turbo.
Home made 2.5-3" Downpipe and 3" exhaust
Spearco Race Intercooler
Civic DX transmission with Quaife LSD
15PSI boost on 93octane gas produced 272hp and 240tq on a dynapack dyno.

As far as suspension, I have a full Acura integra Type R suspension/brake conversion with upgraded 11.8" Front brakes.

I enjoy autocrossing the car, which is why my next upgrade is in the steering and which is why, I will be using a Saxo Steering pump.

[axsaxoman]

simple enough to do-
fit saxo pump unit along with a pwm device to control pump speed-- but not going to be cheap to do

[gpny]

simple enough to do-
fit saxo pump unit along with a pwm device to control pump speed-- but not going to be cheap to do

Thanks for that information! I had never heard of PWM...

What do you think of this module?
http://cgi.ebay.com/Powerful-PWM-DC-MOTOR-SPEED-CONTROL-battlebot_W0QQitemZ190090463903QQcategoryZ71400QQr dZ1QQcmdZViewItem

80AMP Enough and could I use a smaller one?

Next Is it bad for the pump motor to turn at slower speeds with high load, or will it just make the steering heavier?

As for the other questions about fluid resistance when the pump will be off, does anyone here know how much resistance there will be (More or equal to a looped steering box?)

[axsaxoman]

80amp is correct--looks like the right thing.
should be ok
you will never be able to run it with no pump at all as it will be too heavy,but just alter the speed relative to road speed --
can,t say how heavy but on a saxo it is far too heavy --but that is an external ram type of power steeering .

[gpny]

Will running the pump at low speed with the PWM damage it?
Also, I am not familiar with PWM, it I have the PWM running the motor at low speeds, will it heat up significantly? Also, will the amount of current used by the pump be reduced?
How does the Saxo control the pump? Is the pump on constantly at the same speed, or is there an electronic control that varies the pump according to the demand?

[saxoash]

Citroen Saxo electric hydraulic power steering are prone to sticking, i don’t know if this is due to where they are positioned on a Saxo (Right at front at the bottom on the engine so they get splashed every time you drive through a puddle) or the design of the unit itself

I’ve had my power steering pump stick and I’ve had to drive it with out and it’s about 5 Times worse than a non power steering car.


I think Most EPS systems have variable assist, which allows for more assistance as the speed of a vehicle decreases and less assistance from the system during high-speed situations.

[gpny]

I think Most EPS systems have variable assist, which allows for more assistance as the speed of a vehicle decreases and less assistance from the system during high-speed situations.


How does citroen control thier pump? Does the Saxo have a variable assist or is is constant?

Does anyone know where I could get the wiring and hydraulic diagrams for the system?

[supersav]

Slightly off your topic here, but have you looked at the bmw mini pas pump? it's another electric one just like the saxo, but you may find it easyer to get the info you need on it? Just look up an r53 on www.realoem.com and you should be able to find the pluming diagram, it's in section 32 under lubrication system, and your local dealer should be nice enough to enlighten you on wiring issues.

Pete

[gpny]

Slightly off your topic here, but have you looked at the bmw mini pas pump? it's another electric one just like the saxo, but you may find it easyer to get the info you need on it? Just look up an r53 on www.realoem.com and you should be able to find the pluming diagram, it's in section 32 under lubrication system, and your local dealer should be nice enough to enlighten you on wiring issues.

Pete

I Didn't even know the mini had EPS... That would have saved me 50$ - I already have the SAXO pump though, so I'll use that for now.
Unfortunately, I've had nothing but bad experiences when going to dealers to talk about retrofitting their parts to other cars, so my research will need to stay online for now...

[supersav]

you may even find the actual pump unit to be the same? dunno though? that can be your home work. IF you can tell me what power connections you have I'll look up the wiring on a mini to see how they do it and maby you can use a little from column A and a little from column B so to speak. lol

I asume you chaps have the citroen saxo over there, and if so, who is into tuning them? I know you have the likes of turnermotorsport.com, and dinan for minis, but who does the saxo? a carefuly worded e-mail to one of the big tuners may well unveil the info you need??

pete

[gpny]

Actually no saxos here. I live in the US... I purchased the Saxo pump in Belgium on my last trip there.
If I recall correctly the SAXO pump has only 2 wires (I assume +12V and Ground but could be wrong) How does the MINI control its' pump? Does it have multiple sensors/a seperate ecu to vary pump speed, or is it constant?

[supersav]

I'll get back to you.

Pete

[gpny]

any news?
Thanks, Geoffrey

[supersav]

yes mate, sorry for the delay, it's a constant rate on the mini.

only way you'll do it is to use the previously mentioned vareable resistor.

sorry chap.

pete

[gpny]

Thanks.
Do you know if the Saxo pump has a relief valve built in?
Is the Saxo pump on all the time, or is there a sensor on the steering column to activate the pump only when turning?
Thanks for everone's help so far.

[Scott]

the power steering pump only activates once the engine has been started, as far as im aware it is constantly working as long as the engine is running

[Mystic]

the power steering pump only activates once the engine has been started, as far as im aware it is constantly working as long as the engine is running

Yeh i think thats right, when my last pump was on its way out it would hum. The humming was quieter while the car idled but it was still there.

[l1ukeRS]

can you not just use a simple rearstat to control how the pump operates or something like a heater blower resister as they have variable settings im not sure if they could be used but i have used both to control speeds on 12v motors before

[rogerrally]

Re opening an old thread:
Does anyone one know what pressure the Saxo power steering pump runs at?, Im getting 250 psi/ 16 bar on one outlet, and slow running fluid trickling on the other, is that normal, or too low?
Ta Rog, (Newbie)