Xantia timing belt and pump timing

Xantiargh · Unread post by **Xantiargh** » 26 Jan 2004, 15:21

Hi all
Question re replacing the timing belt on my 1995 1.9 TDLX Xantia. I'm having it replaced as I don't think its been done before and the car is on 101k miles.
I understood that resetting the fuel pump (bosch) would be part of the process. One garage included resetting the fuel pump in the belt change quote, the other said the pump wouldn't ever need adjusting and to leave it in the factory setting.
Who's right?
Symptoms on car I'm still trying to shake are:
Poor fuel economy (33 mpg, raising to 35 if tank burnt on motorway (70-80)).
Poor acceleration above 60 (normally; though a couple of times the car has taken off in fourth like the hounds of hell were behind it).
The car never really smokes, even under load.
When starting from cold it always catches first time, and will always keep running, however it coughs grey/white smoke and splutters a bit for a couple of seconds before idling normally (could be waxstatas revs never above 850? glowplugs, etc all replaced/fine).
Disconnected the turbo to see if it was having an effect, and the car was super slow, so turbo definitely producing boost.
I want the pump timing done as I reckon it will improve the mpg and top end acceleration (the car feels like its fighting itself to me, like my old petrol renault 5 used to when the timing was out).
Am I on the right track getting the belt and pump replaced/set. should I be looking elsewhere?

Unread post by **Jon** » 26 Jan 2004, 15:40

The diesel pump is not "reset" at all when changing the timing belt.
Infact, the pump pulley is locked in place at the correct timing mark using a bolt through a hole in the pulley. Likewise, the camshaft and crank pulleys are also bolted in place at the correct timing marks before the old timing belt is removed.
Those Bosch pumps are pretty reliable over big mileages and should not need adjusting, unless of course someone has tampered with it in the past.
Probably a good idea to fit a new diesel filter and air filter and run some injector cleaner through the tank and see if that improves economy and lowers smoke before you even look at the pump.

Unread post by **RichardW** » 26 Jan 2004, 15:47

I wonder if it HAS had a belt change before, and it's been botched (eg the cam or pump is one (or more) teeth out). Having the belt replaced will certainly check the position of the sprockets relative to one another. I would get this done first and see what happens. Checking the actual timing of the pump is a separate operation, achieved by rotating the pump as you would a distributor - a diesel injection specialist can do this. I would be getting the belt done as a matter of urgency if it has done >100k, as it is for sure on borrowed time!
If revs are 850 engine cold, then wax stat is shot / not adjusted properly. The cable should be taut when cold and slack when hot.

Xantiargh · Unread post by **Xantiargh** » 26 Jan 2004, 15:53

"new diesel filter and air filter and run some injector cleaner" - done that; made no noticable difference. Put two air filters, one fuel filter, two oil changes, run injector cleaner for the last 10,000 miles. Economy has not improved.
"see if that improves economy and lowers smoke" - The car doesn't seem to smoke! (I've followed it while a friend drove it around)
I understood the timing belt made sure everything was in line from a valve/piston point of view, but the timing could be advanced or retarded at the fuel pump in the same way as a distributor as well, is that wrong?
The first garage said they would check and adjust the pump using a dial guage of some kind at the same time as fitting the belt, so I guess they see it as two separate timing things...
Where else can I look? Injectors? The mileometer says 101k, but I'm not sure its kosher, though apart from the service history indicating it did 48k in the first two years of its life I have nothing to cause me to doubt it.

NiSk · Unread post by **NiSk** » 26 Jan 2004, 16:31

Sounds like you're turbo isn't coming on song - could be a leak in the charge air pipe or the wastegate rusted up (or a hole in the intercooler). Does the turbocharge gauge show any reading? (assuming its got one).
//NiSk

Xantiargh · Unread post by **Xantiargh** » 26 Jan 2004, 17:03

"Does the turbocharge gauge show any reading?" - No, it doesn't have one.
I've been told its easy to tee one in to the boost pipe (The rubber hose going from the intercooler pipe to the fuel pump, right?). The thing I haven't figured out is where to put the gauge.... cos I assume I have to test boost under load (i.e. I can't have my head under the bonnet at the time!)
Like I said before, once or twice recently the car has taken off in 4th gear, much faster than normal; and smooth acceleration to speeds it would never manage normally.

Xantiargh · Unread post by **Xantiargh** » 26 Jan 2004, 17:07

hadn't finished!
What is the wastegate? Where is it? Can I access it easily (for a citroen) and can I check its not sticking myself?
I would have thought a leak in the intercooler system (hoses, etc) would mean turbo always underperformed; however on the times the car took off it did feel as though something was unstuck so maybe the wastegate is at fault?
Would this explain the poor mpg as well as the performance?

stevieboy1 · Unread post by **stevieboy1** » 29 Jan 2004, 04:17

I did the cam belt on my TD, after that it was never the same.
I checked the pump timing using a gauge and it was out, not buy much. I marked the pump and adjusted you could hardly see it had moved but the guage was then corect, but boy did it make a difference to the performance when it was right. [:D]
I noticed on mine that when you rev it you can see the rubber pipes to the intercooler expand when the turbo comes in. If thats not happening that could point to a lack of boast. You could try disconnecting the pipe(plug the hole) to the wastegate to make sure the wastegate is not opening early. Seen that on a toyota, not a good idea to run it like that as can blow the head gasket if the boast gets to high.

oilyspanner · Unread post by **oilyspanner** » 29 Jan 2004, 12:48

I was once asked to change the belt on a BX where someone had taken the trouble to put short M8 bolts into all of the timing holes! thus rendering the engine impossible to time up, I removed all pulleys, took out the offending bolts and timed it as usual the owner thought I had magically boosted it! Seriously when changing the belt it is important for all slack to be in the rear run of the belt otherwise you could get one tooth off with the fuel pump timing which causes them to run very badly indeed.
Stewart

Xantiargh · Unread post by **Xantiargh** » 31 Jan 2004, 22:34

Well, connected up a boost gauge today and took her out for a spin.
I was using a gauge (by TIM) that goes from -1 bar to +1 bar. When disconnected, or idling, the needle is at @ +0.2 bar. (though the instructions said it should be at 0, so I assumed the readings would be 0.2 bar out...)
When I took the car out for a spin the needle was going past the 1 bar mark with ease so I guess the Turbo is producing normal boost. Once the revs went past 4000(ish) the boost would drop off a bit, so I assume the wastegate is working...
Basically, the car's symptoms are:
1) Never get above 35mpg no matter what type of journey the tank is burnt over.
2) Coughing for about 3-5 seconds on cold starts, though catches first time every time, and never stalls (while coughing it emits white/grey smoke). Have adjusted/replaced waxstat, glowplugs, oil filter, oil change, air filter, fuel filter.
3) Twice recently the car has accelerated faster then normal in 4th gear, pulling smoothly and quickly (not breathtaking, but faster than its day to day performance) from 45 to 90. Normal performance like today, the car would struggle to reach 70mph in 4th. It would get there, but slowly!
4) The car never belches black smoke.... ever! Isn't that unusual for a diesel?
Next on my list is to get the timing belt done. The place (Diesel Service Centre, Peterborough) said they would check the fuel pump timing as part of the belt replacement.
I have a service history, when should the belt have been changed (cr has done 101k miles).
What else should I look at? Injectors? Fuel leak/air ingres?
Advice apprec. as always...

stevieboy1 · Unread post by **stevieboy1** » 02 Feb 2004, 02:10

1 ,my TD only normally returns 35[:(] but it does go up on a run.
2 wait about 3 seconds after the glow plug light has gone out, my starts alot smooother then[8D]
3 not normal, mine will do a ton in 4.[}:)] maybe something to do with boost compensator on the pump, that would lead to a restriction on fuel(compared to normal) if its not working when the turbo comes.
4 you won't normally see it except under really heavy acc, again if the boost compensator not working fueling would be down on standard during heavy acc. Maybe the diaphram (i'm pretty sure theirs a rubber diaphram) has split in the top of the pump?? Thats what i would look at next. you could try disconnecting the pipe and see if its makes any difference

KevMayer · Unread post by **KevMayer** » 02 Feb 2004, 02:45

My Xantia TD gives me just 8 miles per litre which is just over 36 mpg. Thats normal running about and some short motorway bursts. Although, I put Redex in a while ago for a couple of fill ups and took it easy. I reckon I got well over 40 mpg, but, I was going so steady I nearly lost concentration and fell asleep.
My Xantia has got an ECU, EGR, CAT etc and the standard max boost pressure for mine is 0.8 bar.
Your 95 Xantia won't have and ECU etc so should run at 1.0 bar standard.
I have had my speedo needle up to 120. But I wouldn't get near a ton in 4th because the governor wouldn't let the revs go high enough.

KevMayer · Unread post by **KevMayer** » 02 Feb 2004, 03:00

You say you never get any smoke.
It sounds like you have a fueling problem. You should get loads of smoke if you put your foot hard down when you're doing low speed in a high gear. Say doing 25mph in 4th. If I put my foot down at this kind of gear/speed I get lots of smoke.
If you try this and get no smoke then for some reason your pump ain't sending in enough fuel. This could be the max fuel setting screw on your pump. Or, the initial setting of the inverted cone under the boost diaphragm of your pump (assuming you have a Bosch pump). You can adjust this inverted cone if you lift off the cover on the top of the pump and slowly rotate the rubber diaphragm (which the cone is connected to) by say 1/8th of a turn clockwise. This will give you a richer initial fuel setting. If this makes no difference, take the cover off again and put the diaphragm back to where you found it originally.
The cone is inverted and offset. If you turn it more than say 1/4 turn clockwise you start to reduce the fuelling. So, don't be tempted to go more than say 3/16ths of a turn otherwise you'll be going back where you started.