C5 (X7) Suspension Pump Motor service (removal and cleaning)

[Gibbo2286]

Brushes need to be to spec. material wise Chris, the carbon formula used can make a big difference so dodgy cheap aftermarket products should be avoided.

I remember Lucas having a big problem with a batch of starter motors because they got it wrong.

[GiveMeABreak]

The manufacturers of the BHI units are Cinch IIRC, and they are part of the bel group - making connectors for Boeing and the Cray supercomputers amongst others ..... Oh dear, better change that next flight to Airbus.

But seriously, they do seem to have a large portfolio now - and the European Headquarters are in Chelmsford. I suspect the BHIs were a custom project and won't therefore be in their product portfolio.
https://belfuse.com/resources/Brochures ... erview.pdf

[EDC5]

It might not be LDS. Engine oil can also bung things up. And it doesn't have to be a leak. Careless topping up of either could be the culprit.

If engine oil was being sprayed as far as the BHI then I'd have bigger problems than a bit of ingress into the LDS pump motor

Could be the plastic brush baseplate having distorted.

Looking at your photo #6, it does look as if the brushes have a very loose fit vertically in their brass guides. Seems to be a sizeable gap above the brushes, and this is filled with brush debris. Or are those brass tubes lined with something, which would be unusual?

Brushes should be a decent fit in this type of motor, ie they should slide freely in their holders, without sticking and without slop.

Could incorrect brushes have been fitted, maybe at factory?

Yeah, they did seem to wiggle about quite a lot really. Perhaps there was a dodgy batch of brushes going about in late 2008. I'm pretty confident that the carbon dust is what was causing the shorting though. Hopefully it'll be good for another 10 years / 60k miles

The manufacturers of the BHI units are Cinch IIRC, and they are part of the bel group - making connectors for Boeing and the Cray supercomputers amongst others ..... Oh dear, better change that next flight to Airbus.

But seriously, they do seem to have a large portfolio now - and the European Headquarters are in Chelmsford. I suspect the BHIs were a custom project and won't therefore be in their product portfolio.
https://belfuse.com/resources/Brochures ... erview.pdf

Should I phone them up and give someone an ear-full about why they should have used a brushless motor for this application when it would have been the obvious choice for a non-ventilated motor?

[GiveMeABreak]

It would be interesting - but I wonder if they make the whole assembly including the motor, or just the electronic interface housed in the black square unit on top of the motor. If you look below, you can see on this unit the name 'Cinch' and looking at your engine bay photo in the post of the same - you can just about see the same on the right hand side of the unit (with an electron microscope )

I've scanned their literature and can't see any reference - to PSA or 'suspension, BHI, Hydraulics' so I can only assume custom build projects are not openly available and parts are channelled directly to PSA.

Interestingly, they do seem to make a lot of Audio cables and connectors too - and the equivalent of our RCA connectors are referred to as 'type Cinch' in Germany - and also in the RT45 Navidrive manual. That really is my geeky bit done for today

[white exec]

Doubt very much whether they get involved in making motors. As said, connectors are their forte, plus electronic modules, cases, instrument panels, etc.

"Brushes need to be to spec. material wise Chris, the carbon formula used can make a big difference so dodgy cheap aftermarket products should be avoided."
Was aware that brush spec (composition) is a variable, which always makes it difficult to select replacement component brushes. Cheap stuff is rubbish, and so I have tended to go for Bosch or OE parts (where suitable) or something that appears to be better quality. Really difficult issue, as it's usually impossible to know what the spec might have been.

All-in-all, it might have saved a whisker on fuel consumption, or a few euro cheaper, but giving up on the engine-driven hydraulic pump does seem a step backwards. It's not as if they didn't work, nor soldiered on for a decade or two, or more. Maybe that was the point - they lasted too well. A lot of thought must be put into making sure nothing fails under warranty, and then, after a decent interval, everything else fails all at once!

[Gibbo2286]

The Lucas episode I referred to was blamed on a brand new sterile workshop, they reckoned that the air was too clean and to make matters right they had to add what would have normally been considered as contaminants to the menu.

The replacement brushes were marked with a + sign, I fixed a lot of those under warranty.

[EDC5]

All very interesting. probably one of the biggest firms I've never heard of. Could the lip on the brush have been shorting out on the center of the shaft perhaps, as it slid over the commutator bars? I'm assuming that brushes directly opposite each other are of opposite polarity?

I have a suspicion that the mechanical hydraulic pump and motor are made by someone else Marc as when the ecu is removed it appears to have been designed to allow an assembly worker to add the ecu to the valve block as the solenoid coils are in the ecu and the plungers are in the valve block:

All-in-all, it might have saved a whisker on fuel consumption, or a few euro cheaper, but giving up on the engine-driven hydraulic pump does seem a step backwards. It's not as if they didn't work, nor soldiered on for a decade or two, or more. Maybe that was the point - they lasted too well. A lot of thought must be put into making sure nothing fails under warranty, and then, after a decent interval, everything else fails all at once!

I think it's a bad idea too. If they were that bothered, they could have fitted an electromagnetic clutch to an engine driven hydraulic pump (similar to an air conditioning pump) to achieve the slight gain in fuel economy.

[wurlycorner]

There's a massive load of reasons why they swapped from engine driven to self-powered hydraulic pump and I don't think fuel economy would even have been near the top of the list, if it was on it at all.

Bigger issues are that it wouldn't have been compatible with the fully computer controlled suspension (Xantia and xm still use mechanical valves to self level, remember) would therefore have needed to retain all the extra return lines (massive boost in simplicity and reliability in the h3 setup with all that lot gone!) and things like being able to raise and lower the boot level for loading/unloading while the engine is off etc. wouldn't have been possible.

[GiveMeABreak]

I have a suspicion that the mechanical hydraulic pump and motor are made by someone else Marc as when the ecu is removed it appears to have been designed to allow an assembly worker to add the ecu to the valve block as the solenoid coils are in the ecu and the plungers are in the valve block:

That's correct Elis - it's only the hydroelectronic block ECU that is made by Cinch.

[Arnthor]

Hello. I am new to this forum. This tread is very useful to me as I am attempting to repair the motor to the suspension pump on my C5 2006. The 40A fuse kept blowing so I decided to have a look at the pump motor. The fault seems to be the capacitor mentioned in this tread. It appears to have exploded. see photo. I would like to find a replacement. But I am not sure what size (capacity) it should be. Does anyone know the specifications of this capacitor?

thanks in advance. Arnthor

[white exec]

Hi, and welcome to FCF.
Looks as if it says 2.2?F 63v on the remains of the label, but I could be wrong.
A very hefty cable looks to be connected to it, which would be odd for a capacitor of that small value.
Possibly just noise suppression.
Unsure...

[Hell Razor5543]

EDC5, could you tell me where you got the replacement brushes from? I found your blog, and it says that you replaced them.

[Steve Walsh]

EDC5, could you tell me where you got the replacement brushes from? I found your blog, and it says that you replaced them.

This might be of use. https://www.mrcarbonbrush.com/