Help Citroen/Peugeot Diesel Engine problem (Water in Fuel)

mcdreamer · Post by **mcdreamer** » 11 Sep 2007, 11:45

Hi I have posted this in peugeot section as well, but I know some of you guys are experts with the XUD straight diesel engine, so I posted here as well (sorry mods).

Bought a car off ebay recently, was damaged in floods, water contamination to the diesel, looked more like WD40 after I added dry fuel ?? Anyway I have drained the fuel tank and got it running. It smokes white like really bad with a slight tinge of blue. Anyway the lad I bought it off ran it for 3 days with water in the fuel, I thought he would havce damaged the injectors, so I replaced them. It still smokes white but runs alot better, a lot more power now than before, but I can't stop the white smoke. Will this be damage to the fuel system componenets such as injection pump or is it cause I have fitted a timing belt and got the pump timing out (she smoked white before timing belt but also before diesel tank was empty also). I won't let this car beat me. Also I am worried about the fuel pump cause unlike my other 306's it has some electronics on the pump, is this pump the Bosch Semi Eledctric pump (it's definately bosch I just checked) and coiuld the electrics have suffered water damage ??

Cheers Guys

Post by **CitroJim** » 11 Sep 2007, 12:45

Hi and welcome to the forum

Water in diesel will normally be trapped by the fuel filter and settle in the filter bowl so the first thing after a tank drain will be to swap the fuel filter and clean the bowl.

Generally, if water gets into the pump, a very high precision item, it will do damage through corrosion in the longer term. Hopefully, the short time-scale may mean damage has been avoided. However, there are other aspects to consider before condemming the pump.

White smoke indicates incomplete (and very poor - unburned in fact) combustion of the fuel in the combustion chambers. Blue smoke generally means oil being consumed.

How does the engine sound? Is is rattly and not sounding quite right?

How easily does it start?

If the engine took a gulp of water it can cause internal damage through hydraulic locking (water is incompressible) and the usual damage is bent/compressed conrods or valve damage. A compressed conrod will effectively lower the compression ratio and cause poor combustion as will a damaged valve. A leakdown test will reveal this and the engine will be difficult to start.

The electronics should be OK. The pump has no electronics in it as such apart from the keypad controlled stop solenoid (if fitted) and this must be working else you'd not start. All the sensitive electronics are in the ECU and this is well protected against water ingress. Is your engine management light on? If the electronics fail, the pump will revert to fully retarded timing and the engine will run very roughly and smokily (usually black)

Before getting really complex about this, change the fuel filter and dismantle and clean all the air inlet trunking between the air filter and engine, paying particular attention to the intercooler. This can harbour water. Also, change the air filter element.

Post by **CitroJim** » 11 Sep 2007, 13:02

Sorry to multiple post on this but another thought has come to me.

If the engine did take a gulp and say, partially hydrolocked then the cambelt may well have jumped a tooth or two. These engines are very critical on timing and a check should be made of crank to cam to pump timing to eliminate it from enquiries.