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Hey guys,

First of all just wanted to say I have done a search but couldn't find anything on how to do this in an R34, don't know how similar they are to R32/R33's...

I just wanted to find out how hard it is to install a Walbro 550hp intank fuel pump in an R34? And how to go about it? I was meant to be getting it installed by a workshop here in Perth when they serviced it today, but when I got there they told me that my fuel tank needs to be empty to do it so they can't do it today, I would need to bring it back. I am seriously over their bullshit so I don't want to take it back there, which is why I wanted to find out how to do this myself?

I have read that you need to rewire aftermarket fuel pumps in order for them to work properly, is this accurate?

Thanks in advance for any help,

Martin.

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So does nobody know, or is this just such a stupid question that everyone is ignoring me? :D

When the workshop installed my walbro fuel pump a few weeks back they did I with fuel in my tank :(

its so mucch easier and less messy with less fuel in the tank.. it doesnt need to be empty it just needs to be low.. say 1/4 tank.

DIY... its quite easy.

remove the cap, unplug the wires and fuel lines. mark them so you know where they go back on. remove the pump assy.

put it on a bench and basically copy the location and sock height in relation to the cradle with the new pump.

take ya time and use quality fittings and wiring and you cant go wrong

you will need to solder on the plug that comes with the walbro.. cut the terminals off the stock pump and solder on the wire for plug... use heatshrink as elect tape will come off in the fuel.

by fittings i mean hose clamps and fuel hose should you choose to replace them.. i would. get some fuel proof hose and run new length from the top cap to the pump with efi hose clamps either end.

Awesome, too easy :blush: where can I get some good quality fuel hose from?

So I don't need to rewire the pump to give it a more direct voltage like you do with the bosche 040's and 044's?

You do need to rewire the pump - factory wiring is not acceptable half the time. Sometimes its ok, rarely though.

Just read the FI guide and apply the same stuff as the Bosch install, wiring part is the same for all intents and purposes

Shouldnt take long at all, 45mins if you fart around as a first timer would easily have it done :wub:

Given it's winter, emptier tank wont matter otherwise id do it with a full tank personally.

Far less fumes that way, not that anyone would be playing with a ciggie around a fuel tank...

Total bullshit about the tank needing to be empty, whatever workshop said that is retarded IMO.

I've done two pumps, both full tanks. Just remove the pump slowly and there is no mess to speak of really... Just dont drop anything in there :blush:

dont think R34's have variable pump voltage like the 32's do. Someone can correct me on this but if thats the case i would just leave it as it is.

as for fuel hose... most parts shops should have it.. ask for fuel proof EFI hose in 8mm ID

dont think R34's have variable pump voltage like the 32's do. Someone can correct me on this but if thats the case i would just leave it as it is.

as for fuel hose... most parts shops should have it.. ask for fuel proof EFI hose in 8mm ID

Correct, the hose needs to be coated on the outside or it will expand like a balloon causing it to fail. There is proper in tank efi hose but it is $40 a meter, Autobarn could source it but is there a cheaper option?

When I replaced my pump with a walbro it did not give the full pressure, I had to rewire using the stock wires as the feed for the relay and after that was done my walbro would sing as the voltage was was where ti should be. My fuel pressure was spot on after that. Before that my pressure was around 20psi so I am sure there is some sort of varying voltage causing this.

  • 2 weeks later...

Ok well I haven't been on the forums in a while, but I got this installed really easily. Only problem I had was my logic for soldering the new harness onto the wiring was wrong and it swapped the polarities, so initially the pump was sucking instead of pumping :) But I swapped the wires and sorted that out.

Now I just wanted to ask why you need to rewire the pump. The guides I have found don't answer the question, they only tell you how to do it. I have left the stock wiring as is for now because I don't understand why you would need to rewire. Can someone elaborate?

Yeah, but Martin's question is, how does one re-wire the pump to provide moar power?

i.e. 'rewiring' could just mean replacing the wires that feed the current to the pump, or changing the voltage source to a constant 12v, using a voltage amplifier, adding resistors etc...

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