openinverter forum

Hi guys
I bought a Zafira power steering pump a few months ago and finally got round to connecting it up last night.
It works but I was a bit surprised at how loud it is and how much current it draws, at idle it was drawing over 20A and when turning the steering it was over 40A.
Is this normal? Judging by the size of the conductors I guess the current draw is normal as they must be 5mm or 6mm sq

Do other folk have it operating only when moving slowly?
I could live with the noise but 200W to 300W for power steering alone seems a lot.

Alibro wrote: ↑Tue Dec 29, 2020 12:20 pm I could live with the noise but 200W to 300W for power steering alone seems a lot.

Hm... Mine is from Opel Astra G and it draws about 8A on idle.
Yes when full tilt it draws more than 60A! So i use 80A fuse on its line.

Maybe you need to check your steering rack. Maybe its pathways are cloged or something. Pump actually reacts to pressure drop and tries to follow so if yours draws 20A you must have something in the lines that is obstructing fluid flow...

arber333 wrote: ↑Tue Dec 29, 2020 7:32 pm

Alibro wrote: ↑Tue Dec 29, 2020 12:20 pm I could live with the noise but 200W to 300W for power steering alone seems a lot.

Hm... Mine is from Opel Astra G and it draws about 8A on idle.
Yes when full tilt it draws more than 60A! So i use 80A fuse on its line.

Maybe you need to check your steering rack. Maybe its pathways are cloged or something. Pump actually reacts to pressure drop and tries to follow so if yours draws 20A you must have something in the lines that is obstructing fluid flow...

That's a good point, thanks for your reply.
Maybe its the way I have connected it.
The original power steering pump had a banjo bolt connection and for testing I just flattened the area around the case of the pump where the old hose bolted in and bolted the banjo connector to the casing. It works but maybe isn't ideal. I'll get a new hose made up at a local hydraulics shop with the correct connector and see how it goes.

Actually, I think, the pump gets louder and uses more amps when fluid starts moving. A power steering rack should block fluid movement when there's no torque applied to the steering wheel. Then the pump only needs to maintain pressure without flow, which consumes less power.

I agree it's loud and uses lots of current, but there should be a huge difference in the sound and current in idle vs. when turning. As there isn't, the rack could be bad.

Alternatively, maybe the rack might have an overpressure valve that causes flow at the pressure the pump wants to maintain?

Is it possible the rack just isn't bled properly? I've never had to bleed a rack before but I thought it just needed turning lock to lock a few times.
I'm still hearing some gurgling though so will give it another try.

Here is a video I posted showing the issue.

It's 28 A idle in the video, and while it's hard to tell, I guess the idle sound is louder and sharper than it should be. When it's providing steering assist it sounds roughly right.

Can you somehow plug the output and then check whether you get less amperage and noise? This would get your steering rack out of the equation. Keep in mind that it's a lot of hydraulic pressure so be careful. Make sure to bleed the plug.

What fluid are you using? I think I'm using Mobil ATF 220 or something like that in mine and it has worked fine for years.

celeron55 wrote: ↑Wed Dec 30, 2020 8:56 pm It's 28 A idle in the video, and while it's hard to tell, I guess the idle sound is louder and sharper than it should be. When it's providing steering assist it sounds roughly right.

Can you somehow plug the output and then check whether you get less amperage and noise? This would get your steering rack out of the equation. Keep in mind that it's a lot of hydraulic pressure so be careful. Make sure to bleed the plug.

What fluid are you using? I think I'm using Mobil ATF 220 or something like that in mine and it has worked fine for years.

As the pump builds up speed it sounds pretty loud at 8A but is much much louder at 28.
I could give that a try I guess, It should be easy enough to block the output.
I'm using Dexron 3 which I was told was correct for the Rack in the Freelander.

I would go as far as to guess the pump is bad though. Luckily it's not very expensive to get another one to test with.

For the function of hydaulic power steering:

When you don't turn the steering wheel, there should be only low pressuere in the system, the fluid will be pumped around.

When turning the wheel a ventil closes and will push the cylinder to help. Only at the end of the of the steering it get in the maximum pressure and should not be hold there for a long time.

So to check the pump try a closed loop without the power steering rack, the banyo fitting should be fine, don't block the high pressure line!

Check the direction of the fluid in the system, the high pressure line and the return line should not interchanged, check with the original tubing and pump.

Usually modern hydraulic systems tend to have high pressure waiting for flow at idle. I thought it's the case for power steering too. I tried to search for some source that would say otherwise but couldn't find one, can you point me to one?

It would be logical though regarding the general sound of the system so maybe don't block the output after all Allow it to free flow instead.

I only know the old fashion systems, but I don't think there will be a changing for the steering gear. The next step was the direct electric driven steering. Here is a explanation of the funktion from the hydraulic steering gearhttps://www.youtube.com/watch?v=eudfJPHf7DE.
This is the gearing I know from the Opel, VW, Ford, ... as well in electro hydraulic systems.
In older Audi with hydraulic servo brake it uses the same system for the steering as above (non electric) and for brake and chassis it uses a hydraulic pressure accumulator in a seperate hydraulic circuit.

Also i see you start with incorrect sequence. See here:
viewtopic.php?f=9&t=335#p3771

So if you connect thin wires in correct order pump should spool up quickly to full flow (free) at 12A for a second and then settle down to 8A.
Try it and see what happens.

Just having a look at mine, it seems of the 2 smaller wires, if you connect the one without the brown stripe to 12v first then the other it spools up much faster. My cheapo Chinese ebay clamp meter claims 2.7amp when not steering but I doubt that is even close to the correct value.

arber333 wrote: ↑Thu Dec 31, 2020 2:47 pm Also i see you start with incorrect sequence. See here:
viewtopic.php?f=9&t=335#p3771

So if you connect thin wires in correct order pump should spool up quickly to full flow (free) at 12A for a second and then settle down to 8A.
Try it and see what happens.

I think I tried it both ways but will try it again when I get a chance.
After this stupidity I need to reconnect it.

Alibro wrote: ↑Thu Dec 31, 2020 5:07 pm I think I tried it both ways but will try it again when I get a chance.
After this stupidity I need to reconnect it.

This was fun .
Still, why dont you apply one of the thin wires directly to 12V and just touch the other one when you need to start the pump. You will quickly find out which one will provide instant start.

On the other note, i never saw my pump pull so hard when you remove power, even when full of oil. This means motor is running hard! Might be there is a faulty pressure regulator inside.

In the comments of the first video someone linked to this video.
I'm thinking it may be a faulty pump.

Little thread hijack, but I recently had this frame made, giving flexibility to mount the pump on a vertical or horizontal surface. Shouldn't be too hard to reproduce, so If anyone needs one I can get prices to make a few more.

Boxster EV wrote: ↑Thu Dec 31, 2020 6:39 pm Little thread hijack, but I recently had this frame made, giving flexibility to mount the pump on a vertical or horizontal surface. Shouldn't be too hard to reproduce, so If anyone needs one I can get prices to make a few more.

image0 (3).jpeg

Not a thread hijack at all mate. Bang on topic I would say.
So have you connected yours up yet and if so what current is it drawing?

Alibro wrote: ↑Thu Dec 31, 2020 6:54 pm

Boxster EV wrote: ↑Thu Dec 31, 2020 6:39 pm Little thread hijack, but I recently had this frame made, giving flexibility to mount the pump on a vertical or horizontal surface. Shouldn't be too hard to reproduce, so If anyone needs one I can get prices to make a few more.

image0 (3).jpeg

Not a thread hijack at all mate. Bang on topic I would say.
So have you connected yours up yet and if so what current is it drawing?

I haven't connected it up because I cant bear the noise.

I'm thinking about mounting it in a sound proof box.

Boxster EV wrote: ↑Thu Dec 31, 2020 7:00 pm

Alibro wrote: ↑Thu Dec 31, 2020 6:54 pm

Boxster EV wrote: ↑Thu Dec 31, 2020 6:39 pm Little thread hijack, but I recently had this frame made, giving flexibility to mount the pump on a vertical or horizontal surface. Shouldn't be too hard to reproduce, so If anyone needs one I can get prices to make a few more.

image0 (3).jpeg

Not a thread hijack at all mate. Bang on topic I would say.
So have you connected yours up yet and if so what current is it drawing?

I haven't connected it up because I cant bear the noise.

I'm thinking about mounting it in a sound proof box.

It might be worthwhile confirming you don't have the same issue I have. Mine seems to be running full pelt the whole time and is twice as loud as it should be.

Alibro wrote: ↑Fri Jan 01, 2021 1:10 pm It might be worthwhile confirming you don't have the same issue I have. Mine seems to be running full pelt the whole time and is twice as loud as it should be.

Having used a few pumps on builds in the past, as with all second hand car parts its a lottery. A few were really noisy / high draw compared to others.
Will be looking at getting refurbished pumps now using the second hand items for the core charge.

However what held true, bleed the system properly and make sure you use clean correct oil. It will start loud and when it reaches or nears pressure the whine should drop of greatly.

The way I wire them up is, 1 line to IGN and one line to 12V out / working from the DCDC. This mimics the way those lines are meant to be used.

Alibro wrote: ↑Fri Jan 01, 2021 1:10 pm It might be worthwhile confirming you don't have the same issue I have. Mine seems to be running full pelt the whole time and is twice as loud as it should be.

Did you try draining the pump and running it unconnected? My pump without fluid in it consumed 6A.

arber333 wrote: ↑Fri Jan 01, 2021 1:50 pm

Alibro wrote: ↑Fri Jan 01, 2021 1:10 pm It might be worthwhile confirming you don't have the same issue I have. Mine seems to be running full pelt the whole time and is twice as loud as it should be.

Did you try draining the pump and running it unconnected? My pump without fluid in it consumed 6A.

No mate. I didn't try that but for now I've given up on this pump.
I've removed the Freelander power steering pump and am rigging it up with an alternator motor (I built an ebike with it a couple of years ago ) that I plan to drive from an ebike controller. Since taking this photo I've found an old belt that is short enough and made a bracket for it so hopefully I'll be back later with another update.

It'll be very interesting to know how much current and steering assist that will result in. I'm planning to experiment with something similar myself for a cheap "low-tech" conversion. I'm wondering if there would be a little bit of remaining power for air conditioning also...

I've got a 6S 100A controller waiting for this. Got one with 24V capability in case I have to use that much voltage. Not sure how I'll create that 24V though.