Fuel pump problem ?

[Yellowfever138]

Hi - I have a dodge ram srt10 which has never skipped a beat until the other day - as I'm not auto electrically inclined I'm hoping some of you guys might have a few pointers
Engine is modified and is running a paxton blower so has triple walbro in-tank fuel pumps.
Tootling along at 30mph with no load on engine - then nothing no coughing or spluttering just like turning ignition off.
Went to turn engine over -cranking but not firing.
One of the fused links from the pumps had blown.
Replaced fuse and it blew again
I also have a fuel pressure gauge which normally sits at around 43psi before cranking - now after hearing pumps prime the pressure starts dropping off.
Any pointers or how to approach finding fault would be greatly appreciated. Thanks.

[Sardonicus]

Well either the pump as failed something jammed in the rollers or wiring failure (short circuit etc) this is an easy one to diagnose the blowing fuse is directing you to the fault

[stevieturbo]

Yellowfever138 said:

Hi - I have a dodge ram srt10 which has never skipped a beat until the other day - as I'm not auto electrically inclined I'm hoping some of you guys might have a few pointers
Engine is modified and is running a paxton blower so has triple walbro in-tank fuel pumps.
Tootling along at 30mph with no load on engine - then nothing no coughing or spluttering just like turning ignition off.
Went to turn engine over -cranking but not firing.
One of the fused links from the pumps had blown.
Replaced fuse and it blew again
I also have a fuel pressure gauge which normally sits at around 43psi before cranking - now after hearing pumps prime the pressure starts dropping off.
Any pointers or how to approach finding fault would be greatly appreciated. Thanks.

If it is repeatedly blowing fuses that is a big problem. Could be a pump, pumps, wiring anywhere from source to pumps.

Time to do some testing. You could isolate each pump up and apply power from a fused source to try and see if one single pump is the problem.

But without knowing how it is all configured and wired....you'll have to do that investigating. Some people wire stuff in very strange ways.

[GreenV8S]

Disconnect the pump. If the fuse still blows, it's a wiring fault.

If not a wiring fault, see how much current the pump is taking. Then you can find out whether the supply is properly specced for the pump, or the pump is taking more current than it is supposed to.

[Yellowfever138]

Thanks for the info guys - pumps were already wired when I bought vehicle so cant vouch for wiring but ive just been underneath to check for any physical damage to the loom and it all checks out ok.
Sounds like next job is dropping the tank to access those pumps - thanks again.

[stevieturbo]

Try unplugging the pumps first, there should be some sort of connection at the top of the tank whether a plug or bolted connection if there is some sort of aftermarket hanger there with more pumps
Although even with the biggest Paxton available unless you're using ethanol or something, unlikely there's any need for 3 pumps in there.

But until you're inside, really could be anything in there.

[Little Pete]

It’s also worth checking to see if anything else is powered by the fuse.