Xsara pump on BX TD?

jonathan_dyane · Post by **jonathan_dyane** » 10 May 2004, 23:47

Hi guys, I have recently aquired a BX TZD Turbo, which among other faults had a major diesel leak from the diesel pump driveshaft.
When I took the pump off it was apparent the bearings in it were gone and it was pretty knackered...
The only suitable pump I could find was from a Citroen/Peugeot breaker, and was off a '97 Xsara TD, and was a not unreasonable 50 quid. The bloke said it would work fine after I removed all the immobiliser nonsense off it, which I did (lots of shear bolts to tease round...), and fitted my stop solenoid. After I fitted it the car started but ran roughly and with lots of smoke, seemed well retarded, It would appear the initial timing point was different.
I advanced the timing by a tooth of the belt and playing with the slots on the pump and it now runs and sounds lovely. I have done 600miles in the car now and it really does run beautifully, but i am worried the pump might damage the engine because it is from a 1.9td, the BX is 1769. The car really flies, it is far faster than my friends 306td, but I have never driven another td BX so don't know if mine is faster than normal.
The car does not appear to smoke and easily passed a smoke test. As I say it sounds very sweet. Am I asking for trouble here?
Cheers,
'newbie' Jonathan.

AndersDK · Post by **AndersDK** » 11 May 2004, 00:18

Jonathan -
If engine starts and runs perfect, no black smoke, with this pump - what's your problem then ???
The pump's job is to inject diesel fuel in amounts according to wanted engine load, and correct time for perfect diesel engine running.
On diesels there are only 2 major pump adjustments concerning correct engine running :
1) timing the injection
2) avoiding overfuelling (black smoke)
The rest are cold starting/antistall/idle issues.
A diesel can never run "too lean", and any timing problem would defo show as strange running problems.
You have effectively prooved that a BX generation diesel runs just as well with a later diesel engine generation pump, which in fact is no surprise ...

DLM · Post by **DLM** » 11 May 2004, 05:12

.......and you'll find that the bodywork of your BX is a lot lighter than the 306 - as well as having a lighter engine, so giving a favourable power-to-weight ratio. This engine in the BX makes for a real flier.

jonathan_dyane · Post by **jonathan_dyane** » 13 May 2004, 21:18

Thanks for the replies, my gut feeling was that the Xsara pump would be ok, but I just had a niggling feeling there might be a major calibration issue that might cause bother...
Cheers,
Jonathan.

KevMayer · Post by **KevMayer** » 14 May 2004, 01:00

I think the timing advance on the diesel pump of a 97 Xsara would be controlled by an ECU (thats if its a Bosch pump). This is how my 97 Xantia works.
Older, non-ECU, pumps had a speed related timing advance. The roller ring would be advanced by the pressure produced by the vane pump which feeds the diesel to the pump.
So, you may have a pump with nothing to advance it. No ECU and no speed related vane pump pressure. This is probably why the engine ran rough when you first tried it, even though you'd set it up right. I believe that with no ECU connection the timing goes to full advance. The engine would sound really rough like this.
You've now probably retarded the pump a bit by moving it one notch on the belt. does this sound right ? was it moved in the retarding direction.
So, you now have a pump with a fixed timing setting. The fact that it runs well means that you have luck on your side.
Having said all this, it is probably ok leaving it as it is . Especially if you can burn off a 306TD.
I'm fairly sure all this is correct. I got most of it from posts on this great forum. I've spent some time looking into the timing on my Xantia so feel reasonably confident that I'm right.
If anyone knows different, please put us right.

AndersDK · Post by **AndersDK** » 14 May 2004, 03:12

KM -
The timing is not adjusted electronically, it's the precise amount of fuel according to various engine running conditions that's adjusted this way.
Any precise timing adjustment would be provided by electric injectors.

KevMayer · Post by **KevMayer** » 14 May 2004, 03:20

From what I have learned about the Bosch AS3 pump on my Xantia, there is an electrical connection to a solenoid inside the pump. The ECU controls the pump timing by controling this solenoid. So, the angle of the roller ring is adjusted by this internal solenoid.
I have seen posts here talking about just this. Some have suggested that removing the conection to this timing solenoid is a way of testing that it is actually working. With the engine running, you pull off the plug to the pump. The timing imediately goes to full advance and you hear the engine sounding rough. Put the plug back on and the timing is corrected.
Dave Burns..where are you.... save me please
Its good to talk

AndersDK · Post by **AndersDK** » 14 May 2004, 03:51

Hmm..hmm...
I feel thin ice under me feets Kev [:D]
It could be interesting to have this Xsara pump type designation confirmed ?
- just to be sure we are talking same thing here ?
But its highly liky this pump now runs as you describe, with a default (initial) setting, that is SUPPOSED to be controlled electronically.
If the timing has been hit right to make the engine run sweet as a nut (which it appearntly does) then nothing bad in that.
It's indeed very easy to reckon a timing problem by the resulting rough running, which in fact can be scaring, as the engine sounds like it will fall apart ...
But then it supposedly should have a bit of startproblems, as coldstarting is exactly done by altering the injection timing ???

KevMayer · Post by **KevMayer** » 14 May 2004, 04:02

I agree with you Anders.
It would be interesting to know the details of the pump.

jonathan_dyane · Post by **jonathan_dyane** » 14 May 2004, 16:12

Ahh, *but* my pump is the Lucas CAV/Rotodiesel type. The pump had no electronic nonsense whatsoever other than the computer controlled immobiliser and the cold start advance thingy, the same as the BX pump.
I assume this would have been off one of the early XUD9TE Xsaras...
Jonathan.

AndersDK · Post by **AndersDK** » 15 May 2004, 00:31

You're perfectly allright then Jonathan -
Dont worry about our hi-tech details discussions [8D]

aido · Post by **aido** » 15 May 2004, 05:13

as you are talking fuel pumps,just wondering if you guys can throw any light on mine. its a bosch pump on my zx td of 1994 vintage and what happens is this: starting from cold it idles at 950 approx which indicates the cold starting system is working, but starting from warm/hot it idles just below 800 revs for upto a minute making the car shake, then theres like a surge of sorts and the revs rise to just above 800,everything is then ok until i stop the engine and fire it up from warm/hot,then the procedure starts again. dont think its air in the fuel line cos theres no surging at any other times.could it be a temp sensor do you yhink?

AndersDK · Post by **AndersDK** » 15 May 2004, 05:30

Sounds to me like the idle setting needs a bit of adjustment.
Below 800rpm at idle is to my best experience, running around the stallpoint on these midsize (17/19) diesel engines. Try look for any throttle arm stop rest adjustments, then adjust this for approx 850rpm at idle with HOT engine.
Also try with cold engine, that the coldstart bowden cable pulls the timing advance arm fully against the stop. The coldstart idle should in fact intially be just over 1000rpm, some 1050-1100rpm. But me thinks this would be correct if you adjust the hot idle.

Dave Burns · Post by **Dave Burns** » 15 May 2004, 15:28

aido, that the glow plug load on the alternator bringing the idle speed down, when its doing it again press the wire clip on the glowplug relay multi plug and pull the plug off, if the revs instantly rise thats what it is, adjust the idle speed.
Relay is in front of the battery.
Dave

aido · Post by **aido** » 15 May 2004, 21:50

thanks for replying guys, i will try these suggestions and let you know the outcome