How much amperage should twin fuel pumps pull?

**4seasons69** · 02-18-2013

I got my car running yesterday and it's popping the 40amp maxi fuse for the fuel pumps. We put a 50amp in that we had laying around and it ran fine.

The pumps are twin walbro 310lph pumps (Ford gt pumps) with a single power feed. The things I changed this winter is I rewired the sending unit with 10 gauge wire and replaced the strainers on the pumps. I did not use the same strainers that were on there. I used ones that a lot of people on the Ford forums say work well with these pumps and they were in Stock at a local parts store.

Are the new strainers just making the pumps work harder, is it the bigger wiring?

Should I just rock a 50amp fuse or figure out why these pumps are now blowing the fuse. Any input and advice is greatly appreciated!

**Halon** · 02-18-2013

http://www.autoperformanceengineerin...l/fpspecs.html

Are they wired in series or parallel?

That link above doesn't show your pump, but it shows their smaller pumps expected amperage draw to at least give you a little bit of an idea.

**4seasons69** · 02-18-2013

Should be parallel. They have one power feed that splits into two wires. One for each pump. Then they each have their own ground

**JET** · 02-18-2013

10 gauge wire is pretty small for 2 pumps to run off of. It is fine for a single pump. I would double check all the connections and also put a volt meter on them to see what the voltage is at the pump. Something must be messed up in the wiring to pop a 40 amp fuse, especially at idle.

**Halon** · 02-18-2013

So according to my link, a 255hp at 13.5V at a base pressure around 45psi, you'd expect about an 8A draw. If you have them wired in parallel, then I'd expect around 16A total draw.

Your pump is different, but still I don't think you should be popping a 40A fuse.

**4seasons69** · 02-18-2013

10 gauge is small? They were running on 14gauge before and never blew fuses. I will double check all connections. And will double check the voltage at the pumps.

95talonracer · 02-18-2013

Do you have the pumps clamped side by side or do you have a spacer between them?

**4seasons69** · 02-18-2013

Yeah I agree 40 seems excessive. The alternator was putting out about 14.2 v yesterday

**4seasons69** · 02-18-2013

Quote:

Originally Posted by 95talonracer

Do you have the pumps clamped side by side or do you have a spacer between them?

You know what I'm pretty sure they are side by side with no spacer between them

Edit: I just checked a picture I took of the sending unit when it was out and the pumps are touching. You think that could be the culprit?

95talonracer · 02-19-2013

I have heard of thr electrical current or whatever of 2 pumps right next to eachother fighting eachother so some people have added a simple spacer of some sort beteeen the two. Im not sure if you would just use a rubber or aluminum or what but i think it obly nrrds to be a quarter to half incg thich piece.

**4seasons69** · 02-19-2013

I guess that kind of makes sense. Next time I'm working on the car ill figure something out for a spacer and see if that helps

blackawdtsi · 02-19-2013

Don't use rubber if you run e85.

**4seasons69** · 02-19-2013

Why not? Even if it's fuel line? There are already rubber hoses in the tank that connect the pumps to the sending unit

**Shane@DBPerformance** · 02-19-2013

Fuel lines are not made of real rubber.

**4seasons69** · 02-19-2013

Quote:

Originally Posted by Shane@DBPerformance

Fuel lines are not made of real rubber.

Okay cool.

**goodhart** · 02-19-2013

I would just use a small piece of fuel line and slice it open, slide it in between the pumps, then tighten the clamp back up.

**Shane@DBPerformance** · 02-19-2013

There is special submersible fuel line for inside fuel tanks. Most fuel lines can not tolerate fuel on the outside of them and will break down.

**4seasons69** · 02-19-2013

Quote:

Originally Posted by goodhart

I would just use a small piece of fuel line and slice it open, slide it in between the pumps, then tighten the clamp back up.

This is the plan right now. Hopefully this will take care of the problem.

Quote:

Originally Posted by Shane@DBPerformance

There is special submersible fuel line for inside fuel tanks. Most fuel lines can not tolerate fuel on the outside of them and will break down.

I forgot about this. I will make sure I get some that is submersible