Fuel run back

[Razor]

When I have left he car for several hours I won’t start straight away, on investigation it would appear there is no fuel,I then have to crank the engine for several minutes this then flatterns the battery with a jump start it will eventually start.i think the fuel is running back.? Is there a none return valve in the system that would cause this? or am I missing something ?.New fuel filter is on order but don’t know if there is something I am missing.Once started it runs well and when I leave it for an hour or two it starts fine,.

[Bob]

Could it be petrol vaporising rather than running back?

Just a thought, and I don't know if you have that, or diesel.

[Razor]

Sorry should have said 1995diesel auto

[g8dhe]

Quite often on the diesels it can be the seals in the pump that are letting air in and the fuel to run back. Some people overcome the problem for a while by putting a non-return valve in the fuel line, others just replace the seals and cure the problem.

[Northern Bongolow]

See if it's better with the fuel cap loose or off.

The following is usually after running for a while then stopped but it
may be the fuel cap needs washing out, or the one way valve on the fuel tank breather blocked. These can cause a vac in the tank so it sucks back towards the tank when stopped previously.

[mikeonb4c]

When I have left he car for several hours I won’t start straight away, on investigation it would appear there is no fuel,I then have to crank the engine for several minutes this then flatterns the battery with a jump start it will eventually start.i think the fuel is running back.? Is there a none return valve in the system that would cause this? or am I missing something ?.New fuel filter is on order but don’t know if there is something I am missing.Once started it runs well and when I leave it for an hour or two it starts fine,.

As Geoff has said, fuel pumps seals could be the cause. I seem to recall an owner once saying theirs was fine if parked facing down a hill but wouldnt start after being left parked facing uphill. That could maybe be used as a test for cause. Also check Ady's filler cap suggestion. Good luck and keep us posted.

[Russell Jupp]

Does it have 'leak back pipes' from each injector? Little rubber pipes that return unused fuel to the pump.
My zafira had a split in one of these. It would only start if left facing downhill.

[g8dhe]

Yes not sure rubber looks more like a steel tube! 13-6702
http://www.lushprojects.com/bongopartsm ... no=.html#8

[teenmal]

Does it have 'leak back pipes' from each injector? Little rubber pipes that return unused fuel to the pump.
My zafira had a split in one of these. It would only start if left facing downhill.

This is the hose from the l/o rail to the pump.


https://www.ebay.co.uk/itm/GENUINE-MAZD ... 2611799332