walbro 255 retrofit doesnt work

[Kozworth]

I got the walbro 255z gs340 thye one for mustangs and what everyone uses. My old pump was whining so decided to try it out. My old wires from the pump housing to oem pump fit perfectly on the walbro. When I turn key on I can't hear it prime. Whyen cranking it won't start, but when I turn it off I hear the pump buzz a little.

The fpump fuse is in, harness is correctly connected. Do ni need to use the thicker wired harness for the pump (the one that came into the kit). Please let me know thankls.

Car is an 88 325is with the intank pump

[jrobie79]

I used everything in the kit aside from the flexible clear hose. I soldered the new harness onto the existing leads. This was for a 91 318is so YMMV

[Kozworth]

I will try to solder the new harness to existing leads.. any other input

[AndrewBird]

If stock connector fits, there is no need to attach the harness that came with it.

I would double check the polarity of the pump. You may need to switch the stock wires around if the pump is opposite of stock. Also make sure you are getting power to the pump.

It's possible as well that you got a bad pump, even though it is new. Try bench testing it by hooking power to it directly.

[Kozworth]

I'll double check polarities but testing a pump not submerged is bad. Gasoline cools and lubricates the pump

[Fusion]

I don't think you need to worry about running it "dry" for a couple seconds.
I soldered mine in also.

[uberCerealkiller]

If you are worried about running it dry, get a small "dish" or "bowl" put some gas or fuel cleaner or something like that and bench test it.... just make sure you don't allow any sparks....could be bad.

But yeah, i've bench tested a million fuel pumps dry, doesn't hurt them as long as its just for a second.