SMOKEY XSARA TD

talbotsteve · Post by **talbotsteve** » 20 Mar 2007, 21:12

Hi, i've just taken on an r reg xsara 1.9 td, it has recently had a 2nd hand replacement engine fitted along with the original engines fuel pump/injection unit, however it sounds very hunty and rattley at low revs regardless of whether warm or cold (my bx does when it first starts but soon quitens down as it warms up), and it produces lots and lots of black smoke under load and over 3000 rpm(smells like fuel) plus it is quite low on power.l'm pretty sure its not the turbo as it is a lowish mileage turbo. Another thing i have noticed is that the engine has done less than 2000 miles since fitting and had an alledged oil change when fitted yet the oil is thick and black already???
I am just wanting to know, if the fuel pump is one tooth out on the belt either way will this make it smokey and low on performance??
And how difficult is it to pop the pulley forward or back one tooth just to try it out??
Any ideas welcome
Cheers Steve

AndersDK · Post by **AndersDK** » 20 Mar 2007, 21:26

Diesels returns quite a lot of deposits to the engine oil. Oil looks dirty within few 100 miles.
Knowing this should make you think, as carbon deposits in the engine oil is an effective grinder of engine internals ...

It is most important to keep up with oil change intervals on a diesel for this same reason, no matter WHAT type, kind, make, quality of oil you are using.
Aquiring a 'new' car always means a change of oil & filter if the oil does not look bright new on the dipstick.

I agree you have a problem with the diesel pump. Before getting into any costly affairs, you should know that it is a common tweak to turn up the fuel volume to get more umph from a TD. Overdoing it just the slightest amount - or if the pump originally was adjusted for another engine - will produce fantastic amounts of black smoke and sluggish power.

Diesels are quite complicated to get within good fuelling range for the average DIY'er. In this instance I'd recommand you spend a vist to an independent diesel specialist garage. Its like getting a new car when things are optimal adjusted ...

jeremy · Post by **jeremy** » 20 Mar 2007, 21:39

Black smoke on part throttle suggests poor atomisation to me (ie droplets are too big and burn on the outside only) - which generally would be a sign of injector wear.

I suppose its possible that the injectors and the pump are incompatible (ie designed to run at different pressures)

I don't think its the turbo. When running the additional fuel is supplied in response to boost pressure only - unless you have a modern variable geometry turbo - if it doesn't work properly you'll not have any boost - so no additional fuel.

The pump can't be delivering too much fuel at low throttle openings as engine speed and hence power output is dependent on pump output. (more fuel - more engine speed)

Post by **philhoward** » 20 Mar 2007, 21:44

It could well be stuck at the maximum cold advance setting on the pump - i'm guessing it'll be an ECU-fed version so check the ECU temperature sensor as well as the advance solenoid (they do have a habit of sticking).
My last ZX TD (non-ECU, but similar setup) was stuck on the cold advance setting; idle speed was always over 1000rpm; it rattled and clattered a bit plus smoked like a chimney if taken above 3000rpm.

Given the state of the oil, best check the air filter as well...but oil does go black almost as soon as its in the sump!

If the belt was a tooth out, i'd actually expect white smoke...

Post by **CitroJim** » 20 Mar 2007, 21:46

Sounds very much like the timing is out and if the pump has been transferred to another engine, it is quite possible that not enough care has been taken in timing it to the new engine. Timing on a diesel is critical and must be carried out using a dial gauge. Putting it more or less in the right place or timing by ear is not really good enough.

I'd firstly check that the belt is timed correctly according to all four timing holes (Cam, Crank, 2 x Pump). So many avoid the crank (flywheel hole as it is difficult to get to and it is so easy to have it slightly mis-timed if you don't use it. If all checks out here Ok then pump timing needs to be checked.

Which pump have you got? Lucas or Bosch. The Lucas is slightly easier to time although both need special adapters/tools in addition to a dial gauge.

I second Anders suggestion that if tests point to the pump timing or if the fuelling has been twiddled with it is best to consult a diesel specialist. Fuelling can be tweaked in an attempt to cover up what may originally have been a timing error.

Post by **CitroJim** » 20 Mar 2007, 22:06

philhoward wrote:It could well be stuck at the maximum cold advance setting on the pump - i'm guessing it'll be an ECU-fed version so check the ECU temperature sensor as well as the advance solenoid (they do have a habit of sticking).

Good point Phil. If it is ECU controlled then the pump itself will be largely free-timed mechanically and it relies upon the TDC sensor, Coolant Temperature Sensor and Injector Needle Lift sensor to set timing. Any one of these sensors could be the cause of the problem.

Given the engine has been changed and the original pump retained, is the pump working with the correct set of injectors? Lucas pump trying to drive Bosch injectors or vice versa. That would also give these symptoms I reckon.

talbotsteve · Post by **talbotsteve** » 21 Mar 2007, 16:57

thanks for the advice guys i will go away and take a look,
cheers steve

Brian UK · Post by **Brian UK** » 23 Mar 2007, 00:18

Don't know if it is still the case on the later engines, but both Bosch and Lucas pumps were incompatible with the other's injectors, as the injection pressure was much higher on the Bosch. Thus if you have ended up with a Bosch pump and Lucas injectors, you will be overfuelling.

talbotsteve · Post by **talbotsteve** » 23 Mar 2007, 18:27

Right, i have been checking around (mainly my fatha's xantia td estate and ebay) and it seems that most xantia's if not all have bosch pumps, and the one now on this replacement xantia engine in the xsara is a lucas pump?? Now the garage did say that they put the old xsara pump on this xantia engine which would explain this, but if they haven't swaped the injectors over then this should if i read the above posts correctly cause over fueling and poor performance/smoke?
Now i have a 1.7 bx td engine with a lucas pump on it, my question is would i be able to use the injectors out of this engine or are the 1.7 lucas injectors different to the lucas 1.9 injectors?
Cheers steve

Post by **philhoward** » 23 Mar 2007, 18:31

The fuelling will be all over the place if you have the wrong pump for the injectors, and as far as i'm aware, 1.7 and 1.9 injectors are different.

Stewart(oily) · Post by **Stewart(oily)** » 23 Mar 2007, 21:08

I am unsure about the differences between 1.9 and 1.7 injectors but bosch and lucas ones certainly have different lift off pressures, a quick phone call to your local diesel specialist might help, check your injectors match your pump, I have a set of Lucas ones (1769 TD) spare, PM me if you need them.
Stewart

talbotsteve · Post by **talbotsteve** » 24 Mar 2007, 14:14

Thanks for the offer stewart i will get in touch if i need them,
cheers steve

talbotsteve · Post by **talbotsteve** » 09 Apr 2007, 17:35

Right, i have today found out that the injectors are lucas and came off of the same engine the pump came off, so i have fitted a boost guage to check the turbo pressure and found that it only boosts 0.3 bar at 3000 rpm and a max of 5.0 bar at a whopping 4500 rpm???? thought they should be a bit higher boost at a wee bit lower rpm????
any ideas as to whether this is contributing to my smokey xsara??
cheers steve

Stewart(oily) · Post by **Stewart(oily)** » 09 Apr 2007, 19:16

That is too low, standard boost should be in the region of 11-15 psi (on my gauge)
Stewart

Post by **CitroJim** » 09 Apr 2007, 21:12

talbotsteve wrote: max of 5.0 bar at a whopping 4500 rpm????

5.0 bars

That 73psi in old money!!! I reckon you mean 0.5 bar and yes, very low indeed.

You have either a wastegate stuck open, an exhaust manifold leak, a split in the turbo trunking somewhere, a split in the boost sense pipe to the injection pump or a holed intercooler.

Check the trunking first. That is the most likely cause..