Anyone good with fuel pumps??

[Speed_Freak]

Ive got a problem thats starting to p*** me off and wondering if any of you guys have any ideas.

I took the fuel tank out to get it repaired cause it was leaking, so I got that done, hooked the fuel pump (VL) back on turned the key on and donk, nothing.
I then got a bosch 350HP pump, fitted it mint started ran fine but had a funny noise all the time like a wee electric motor with a 9V hooked up to it It then gave up after about 5hours of driving (the second time I drove it).
So I thought F it, Get another VL one. Fitted it up today and thought that having no filter between the pickup and fuel pump may have blocked the pump, but it didnt, it primed up the relay switched off and then it never worked again.
Now I checked the voltage going to the pump at the terminals and its about 12.10 volts when you first key-on then ticks off (0V)after 3 seconds, then when you try start the car it regains 12~Volts, so the relays working fine no voltage spikes. Now im beginning to wonder if the fuel pressure regulator/filter is blocked which is not releasing the pressure and therefore overheating the pump?? Does that make sense? Does anyone have any other ideas on why it would do this?

Any help would be appreciated before I shoot it

[brocky41]

Make sure its not blocked before the pump aye - if youve had the tank repaired could be sumething jamned up the outlets if they filled it with water - cloth or the like.
check the return line to maybe??? - hope this helps

[Speed_Freak]

Its definately not blocked before the pump or the pickup. You can blow thru it with ease Im guessing it has to be something to do with that return huh

[Bartman]

That's the next place to check. If you dead-head a high pressure efi pump, the pump will die most quickly. Perhaps see if you can blow down the return line, or if your fuel reg is allowing the surplus to bypass or not.

[Speed_Freak]

I had a quick fiddle round tonight
*Fuel filter was full of silicon shit, replaced
*Blew thru the return line, returning to the tank as normal
*Back blew thru the supply, a bit of crap came out, but still normal
*Manually hooked up ANOTHER fuel pump (got for free yay) to a 12v battery returning into a fuel can, pump worked mint. (not going to install it until I check FPR
*Priming voltage 12.4 volts, cranking 11.3volts from the + and - of the fuel pump terminals

So the pump cant be getting too much voltage, or have blocked lines, it has to be either something to do with the fuel pressure regulator (stuffed?) or the pickup?

[Lulu]

*Manually hooked up ANOTHER fuel pump (got for free yay) to a 12v battery returning into a fuel can, pump worked mint.

Free Fuel pump for the win...the only silver lining to my rusted Datsun

Sorry this isn't a helpful comment Matto... Fix it fast so I can annoy you about giving me a seat for the cruise

[Dattochriswagon]

Yeah dude you gotta come on the cruise and fill up with your datto girls!

[Speed_Freak]

Wont be going anywhere fast at this rate

[Speed_Freak]

Got some work done on it tonight finally.
Hooked up the fuel pump in a can with a 12v battery, worked mint.
Tested flow thru the pickup, mint
Hooked the fuel pump 12v battery onto the pickup and plumbed it back into the return line, worked mint
Hooked up the power from the coupes electrics.. fingers crossed, and it worked !!

Now all I have to do is put the new filter on and hope like hell it was just a clogged up fuel filter and not the regulator and we'll be rockin again!!

[Dattochriswagon]

Woo hoo! Stoked dude!