Forum:
Friend of mine has a 2.8 turbo Fieldman, same as mine, but is having fuel problems. When the engine is revved up for a while, the plunger on the primer pump above the filter begins to drop down, and he gets problems trying to get fuel power/high revs whilst driving.
It isn't a vacuum in the tank that's causing it, because we took the fuel cap off and it made no difference. He's put a new filter on (the old one was quite mucky), but that hasn't helped either.
Finally, we took the whole filter/bracket/primer pump assembly off mine and swapped onto his. Then it worked perfectly. So he got a replacement assembly from the scrappers, but now has the original problems again. Do you think he's just unlucky to get another filter bracket/pump that has the same problem as his original (is there something which happens to these over time), or is there something else going on here?
Any ideas gratefully received. Thanks.
These have a non return valve
These have a non return valve fitted into them to prevent fuel running back, or being syphoned back to tank, these often leak, but if stood for some time without diesel in them, or are cleaned and stored without being lubricated, sieze up and severely restrict fuel flow.
One other possibility is the fuel pick up pipe in the fuel tank, these have a filter on the end to prevent tank debris entering the main filter, sometimes they degrade and act like a flap, the bottom is sucked over the end of the pick up pipe and severely restricts fuel flow from the tank.
Also check the fuel shut off valve on the fuel pump, over time they go weak and severely restrict the fuel flow as they don't open fully, but close properly under the return spring pressure.
Thanks very much for the
Thanks very much for the pointers. Whereabouts is the non return valve? I'll check it out.
I think the pick up in the tank is probably ok because we tried sucking the pipe and the diesel came through very easily. Also when we changed the filter assembly for the one from my car, it ran perfectly. As far as I can tell, it is most probably something to do with the filter assembly, but I can't really see what can go wrong with these as long as a good clean filter is fited.
The non return valve is
The non return valve is located inside the filter housing, and nigh on impossible to remove without damaging the finter head unit, try for one off a breaker with the engine in it, and still running. That way you know it is fine and lubricated.
Filter, not finter.
Filter, not finter.