X7 fuel supply problem

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Peter.N.
Donor 2020
Posts: 10550
Joined: 02 Apr 2005, 16:11
x 481

X7 fuel supply problem

Post by Peter.N. »

I couldn't find my original post so have started a new one. The red car has for sometime been cutting out on steep hills. It started a couple of years ago going up to Tan Hill in Yorkshire, it died on me but on releasing the throttle it came back to life again, a bit further up it did it again. Had no problems all the rest of the time we were up there so I forgot about it.

Some time later my wife borrowed it and it cut out on her going up a steep hill, doesn't happen when I drive it as I rarely if ever completely floor the throttle. I decided to change the fuel filter which seemed to make it worse, it was happening to me as well. The old filter was covered in what looked like some sort of fungus, so I removed the tank unit because I suspected it might be in there as well - but it wasn't.

After I put it back together it ran fine for sometime but then stopped half way up a hill in a very narrow lane when I was driving it, the primer bulb had gone soft so I pumped it up for some time before it started, I drove home which was also uphill keeping the revs up above 2000 and got home OK.

I closely examined the system for air bubbles and found a stream of very small ones coming up the feed pipe, you could only see them if you shone a light through the clear plastic section, the next time I used it all was fine, but I went up the hill through the forest a few days ago and it stopped, couldn't start it this time so I rolled back down the hill and swung hard round so I was actually facing down hill - it started.

Today as the weather was quite nice I had another look, it started OK on the level although it did stop after a few seconds but then started again, I drove the front up a ramp to try and reproduce the fault condition's, sure enough it stopped but no signs of any bubbles in the fuel line. I got it started again and kept the revs at about 2500 and it ran for a few seconds then attempted to cut out didn't make it and picked up again, from then on it ran perfectly.

The fact that you have to pump the primer to get it to start seems to indicate it must be air getting in, but where? There was no air in the feed pipe feed pipe as if the fuel was draining back to the tank. Any one got any ideas? :? :( :oops: 8-[

Peter

JohnD
Donor 2019
Posts: 2631
Joined: 15 Mar 2001, 00:41
x 60

Re: X7 fuel supply problem

Post by JohnD »

How full is the fuel tank? Our old Saxo tends to do the same when coming up a hill once the fuel gauge gets to only about a quarter full.

Peter.N.
Donor 2020
Posts: 10550
Joined: 02 Apr 2005, 16:11
x 481

Re: X7 fuel supply problem

Post by Peter.N. »

Doesn't make a lot of difference, I think it was about 3/4 full when it happened to me, although it is worse when the fuel is low. I'm pretty sure its air ingress, will do some more experimentation.

Peter