1998 Xantia 1.9TD Engine Runaway

acrowot · Post by **acrowot** » 10 Aug 2006, 13:14

Hi Jeromy, I did wonder what that was but I did replace the whole assembly and clear pipe to the injection pump and filter and filter seals but the air was still present, it did dissappear on bleeding but returned after starting the engine and running for a few minutes. After taking the car for a run I can no longer see these bubbles and the engine really is sweet, started first time this morning no problems no smoke. The reason for the "runaway" though is still unclear, will it return?.

acrowot · Post by **acrowot** » 10 Aug 2006, 13:22

acrowot · Post by **acrowot** » 10 Aug 2006, 13:23

acrowot wrote:[From what you said no/few bubbles before filter and lots after sounds as if the filter is sucking in air causing the problems you have experienced. Dont quote me but i think there are 2 types of fuel filter for this car. One filter is a screw in canister with a plunger on top which rarely sucks air. The other fuel filter is mounted on top of the thermostat, it has 4 allen screws holding the top down and a water drain tap. This second type are known for sucking air.
The 3 main places it sucks from are the drain tap, the lid as either the seal on the filter is rubbish or not done up correctly or the seal between the filter houseing itself and the metal underneath can go and let air in.
All fairly easy things to fix though the last one requires a coolant drain.

hth Simon

Hi Caveman, mine is the second type but I did replace the whole thing, I did not drain the coolant to do this and there was no coolant leak, do you say there should have been, if so I may have another problem.

jeremy · Post by **jeremy** » 10 Aug 2006, 14:35

These may be of interest:

http://www.frenchcarforum.co.uk/forum/v ... hp?t=17179

http://www.frenchcarforum.co.uk/forum/v ... hp?t=17271

It won't necessarily leak fuel to the outside but can still let air in.

weety · Post by **weety** » 10 Aug 2006, 15:39

jeremy wrote:These may be of interest:

http://www.frenchcarforum.co.uk/forum/v ... hp?t=17179

http://www.frenchcarforum.co.uk/forum/v ... hp?t=17271

It won't necessarily leak fuel to the outside but can still let air in.

as a detection method (and a good way to start diesels reluctant to start) you can disconnect fuel feed lines at various points and connect them to a funnel filled with diesel.....that way you should be able to work out where air is getting into the system.....

i have never used this technique to find an air leak but it works every time if you are having trouble getting diesel up from the tank (after its run out of fuel etc etc)