Replacing BX's HP pump with that of xantia

FrankBo · Post by **FrankBo** » 14 Apr 2008, 19:06

Hi, i have a 92' BX 1600 with power steering. I had fast ticking in HP pump
and leak LHM from flow distributor. I've just replaced flow distributor by a good used unit but fast ticking only a little better and steering now harder.

I'm going to clean circuit with hydroclean but i'm thinking better solution
is fitting a 6 + 2 HP pump (a good unit from scrappy). What do you think about? Someone have done it?

Thanks in advance

Frank

citronut · Post by **citronut** » 14 Apr 2008, 19:13

have you fitted a new acumalater (regulater) sphere as a flat or partly flat sphere is the usual thing which causes fast ticking of the regulater
regards malcolm

jeremy · Post by **jeremy** » 14 Apr 2008, 19:47

Fast ticking is NOT caused by a weak pump.

As Malcolm says - is the accumulator good? (used on 6 x 2 pumps as well). Test it by getting the car to normal height and let the engine idle for a couple of minutes. Turn off the engine and sit in the boot. The back should sink a long way and then rise to its original height powered by the accumulator.

The behavior with the engine off should be the same as with it running.

ellevie · Post by **ellevie** » 14 Apr 2008, 20:09

The back will only sink a "long way" if the rear spheres are in good condition --- the distance it sinks is an indication of the sphere pressure. There is even a formula to estimate the pressure,
http://www.frenchcarforum.co.uk/forum/v ... 2&start=15

FrankBo · Post by **FrankBo** » 14 Apr 2008, 21:13

citronut wrote:have you fitted a new acumalater (regulater) sphere as a flat or partly flat sphere is the usual thing which causes fast ticking of the regulater
regards malcolm

Accumulator sphere is fine. HP pump ticking before flow distributor replacing was 5/6 seconds; now after replacing it's 10/12 seconds about.
I think it's due to one or more of following:

- Internal leak from flow distributor:
- Pressure regulator not running well
- Old LHM maked garbage into hydraulic circuit (Hydraflush may help)

LHM is old (7 years or more), i have a good used pressor regulator
and i could replace it. I think better solution to remove flow
distributor and fit Hp pump 6+2 (more reliable)

citronut · Post by **citronut** » 14 Apr 2008, 22:26

was it a new A/C sphere fitted or a second hand one, the other thing which can make the regulator tick is posibly the regulator valve ball bearing needs reseatting, i have not done this myself but others on here have,

dont try and make the BX system more complecated like the XANTIA
regards malcolm

AndersDK · Post by **AndersDK** » 15 Apr 2008, 01:08

Hi Frank -

Before doing anything drastic, please check the return flow from the various reservoir rubber hoses - only the small diameter hoses. NOT he 2 large diameter hoses.

Such a test will immediately point to a leaking component in the system.

Wellknown candidates are :
1) the front struts
2) the brake doseur valve.

PS : forget about the Xantia pump. The Xantia pump runs off a multirib belt, while the BX pump runs off the standard V-groove belt.
Trying to modify the BX to fit the Xantia pump is masochism - you wil torture yourself with all kinds of brackets, extra bolts ec. that cannot withstand the belt tension in the end

jeremy · Post by **jeremy** » 15 Apr 2008, 20:58

A common cause of fast ticking with a sound accumulator is wear of the regulator non-return valve seat.

Basically LHM can escape from the accumulator in 3 ways - onwards to the safety valve as is intended, down the piston/valve visible when the sphere is removed and back the way it came - which should be shut off by a non-return valve.

The valve is a simple ball bearing retained in position by a plate and bolt visible when the sphere is removed. It can simply be re-seated by removing the bolt and collecting the ball (your eye socket is effective - be careful).

Stick the ball back in the hole and tap it smartly (ONCE ONLY) using a BRASS punch. Re-assemble.

You must only hit it once - multiple blows will produce overlapping seats which will not work. You must NOT use a steel punch - it'll put a flat on the ball which will of course not seat.

FrankBo · Post by **FrankBo** » 16 Apr 2008, 01:30

Hi, thanks a lot to all for reply; last year i checked the return flow from rubber hose (small diameter) and only brake doseur valve hose returned
a little quantity of LHM.

Then i checked also big diameter hose and only from pressure regolator
return hose returned a big quantity of LHM.

I thouhgt brake doseur valve don't fault because breaking very good, so
now i think fast ticking is due to pressure regolator fault.

I'll check ball bearing as suggested.

bye

citronut · Post by **citronut** » 16 Apr 2008, 13:34

the BX syndrom where the rear of the car sinks after engine is switched of, is due to the dozer valve internal seals not holding up the rear suspention presure, but it dose not affect the braking at all
regards malcolm

FrankBo · Post by **FrankBo** » 16 Apr 2008, 20:50

When i switch off engine, the rear of the car sinks in a few minutes .....
Now i think i'll replace brake doseur.

Regards

jeremy · Post by **jeremy** » 16 Apr 2008, 22:41

Sinking at the rear when the engine is turned off isn't anything to worry about unless you need to make a quick getaway.

Doseur valves are quite expensive and the chances are the new one you'll get is just as bad as the old one. (There was a suggestion a while ago that the new ones weren't as tight as the ones used in production)

Having had to remove the doseur from my DTR Turbo to replace a rotten return pipe I can honestly say that I hope I don't have to do that job again - and if I did I'd seriously consider removing the engine and gearbox. A RHD BX 16 will be easier but still an awkward job compared to a LHD car.

An internally leaking accumulator will allow the car to drop slightly quicker as it will not top up the suspension when the height controller valve opens.