XM 2.1 TD fuel running back to the tank

[red_dwarfers]

I've had an issue with the XM for a good year now where if I park pointing up an incline, the fuel in the line appears to run back to the tank overnight. My current workaround is to park the car nose down.

Until a couple of months ago, if I started the car after leaving it overnight it caught and fired up immediately for about a second then stalled. If I then turned the ignition off/on and turned the starter I sat there for about 5-10 seconds and nothing happened. If I then used the priming bulb it caught and fired up immediately.

A couple of months ago I changed the fuel filter, leak off pipes and the rubber part of the priming bulb. The fuel pipe on my XM is larger than the Xantia so I couldn't swap the whole priming bulb over. Starting was noticeably easier, it would fire up for a second and stall but after turning the ignition off/on I would wait around 5 seconds and it would catch.

A couple of days ago I replaced the bit of pipe between the fuel filter housing (I have the later housing which looks identical to to 1.9 Xantia, also takes the same filter) and the fuel line that goes to the EPIC pump with a longer transparent flexible hose. I made sure the car would fire up and run then stopped it and used a G clamp to squash the flexible pipe and left it overnight. When I took the clamp off and started the car, it caught immediately which in my mind points to something between the flexible hose up to and including the pump. I'm going to do that test again today and tomorrow to see if I get the same results.

I have noticed a few small air bubbles running along the pipe between the fuel filter housing and the pump. I'd say on average about 1 every 30 seconds.

Shouldn't the one way valve in the priming bulb stop fuel running back, maybe I need to get a known working one to answer that.

I have a spare fuel filter/thermostat housing from a 1.9 Xantia which I'm assuming is sweet but I can't be sure. I also have the fuel filter housing on WOR which I know works. How much of a job is it to take off, will I have to interfere with the coolant side of things?

Does anyone have any thoughts?

[kenhall1202]

Hi Kev

I would double check the leak off pipes for a tight fit on the injector nipples, including the blanking plug and section where the leak offs return to the pump connection. I was caught out by using dubious quality leak off pipe which swelled and split. AFAIK the only other place where air could get into the EPIC pump is via the drive shaft seal.

Ken

[Peter.N.]

Sounds as though you have done nearly everything Kev, one thing though, check the plastic fuel pipe where it connects to the metal pipe behind the engine near where the heater pipes go through the bulkhead, they can crack at that joint and cause air ingress.

Peter

[Peter.N.]

Another case of slow typing

[red_dwarfers]

Thanks both, I picked up a length of fuel pipe today and I'll starting replacing the pipes one by one. I've just replaced the one between the fuel filter housing and the pump, we'll see how well it starts up tomorrow!