Club 80-90 Forums

After 10 months still having trouble with my electric petrol pump failing. I have tried checking everything in the elecric system and after 7 replacements faililing am ready to give up. After cleaning out the tank several times whilst draning it every time I change pumps 6 by the way I had it running again and started it every day for a week but yesterday no start again. It seems possibly after rainfall perhaps, anyway after several auto electrician and mechs I am at the same position. When its parked surely there is no voltage going to the pump unless I have loom short somewhere or alternator problem? Any suggestions ?

Which pump make/model are you fitting and what sort of mileage between each failure?

I have used several makes including bosch,Jp and copies The engine is a 2.1 DJ 

I forgot to add no milage except 1mile to garage for MOT between pump failures. Passed MOT though!. The pumps have failed just standing on the driveway and occasinal starting just to see if ir was still working.

relays and all that OK?

Relays checked and now OK but have failed a few times during the period thus thinking there must be a short circuit somewhere. I intend to check behind the fuse box as it gets damp with a leak when raining and according to the wiring diagram a double connector is there somewhere.

Are you saying there's constant 12 volts going to fuel pump, even with ignition switched off?

Have you verified the pump is faulty, by jumping a new 12v line straight to the pump from The battery? Or even a different battery. You can safely run the pump from a different battery(or same battery with fly leads), It will just circulate fuel through the lines and back to the tank.

ground or connection problem maybe?

No live at pump when ignition switched off. Took live direct to pump and pump is dead each time it happened. Each time a new pump was fitted it ran OK I even took it for MOT and drove it back. But after standing for a few days or more its gone again. This started last december and during lockdown I have been trying with others to get it going, I have tried changing everything including rebuilt hall dissy, new ignition conttrol unit, new ignition switch, new plug and leads , new coil, changed petrol pipes, even tried another ecu which I had but with no effect. If the pump keeps going I must be getting a live down the earth so maybe the loom is suspect? My expensive auto electrician was baffled.

Looking at your reply above - you have run a live direct and the pump is still dead, have you run a fresh ground??? If your ground is dodgy this would explain it.

I haven't yet but that is my plan also this week in a final push to try and get it on the road at last. 

Also, consider fitting a battery isolator switch beneath the driver's seat. I use mine even when stopping for refuelling. Just a habit now.

If all the wiring checks, Earth, 12v supply via ignition only are found to be good then I would dismantle one of the faulty pumps and try to establish why the pump has failed. The pump is an electro mechanical device and it is unlikely that both sections of the pump have failed. You should also take a resistance reading across the positive and negative pump terminals before dismantling to establish if the fuel pump has gone open circuit.

The pump failing when the van has been stood idle suggests it may be operating all the time or that is just a coincidence and it fails to function for some other reason but you could replace the pump, take it for a drive then park and disconnect the feed to the pump. A few days later, connect the pump and see if the pump functions.