Hi. I have a 1973 Corvette that I have done an LS7 swap on. I’ve just had my 3rd Walbro 255 pump die on me, each of them only lasting about 100 miles. I’m going crazy trying to figure out what’s causing the issue. Maybe I’m just unlucky and keep getting duds but after 3 pumps I find that unlikely.

The setup I’m using is the in-tank fuel pump kit from Tanks Inc. (link to kit: https://www.brphotrods.com/p/325-6680-04/68-74-corvette-efi-fuel-tank-kit-255-lph-pump.html) I am buying these replacement pumps from a reputable source and can confirm they’re genuine pumps. I have a clean ground and 12v power running through a relay running on a 15a fuse. I never let the gas tank go below half full, ever. I’m using the corvette returnless fuel filter setup. I’m using 12AWG wiring. My gas tank and fuel filters are all clean, no debris.

When the pumps die, it’s sudden. No odd fuel pressure, no odd noises, no odd voltages, nothing. They just stop working and never come back to life.

Is there something else I should be looking at? Or perhaps there’s another fuel pump alternative I should switch to instead? I’d like to be able to enjoy my ride and not tow it every 100 miles. Thanks in advance.

 

Might be helpful to do a quick bench test on the pumps. Just hook up power and see if it works and how it sounds. Measure resistance of the motor windings. Visually check if there are any cracks around terminals. Check that the inlet is not plugged up. And then do a full tear down to find what might have gone wrong.

If you can find a failed part then you might be able to better speculate why it failed and hopefully address the cause.

 

This might seem like overkill, but have you considered running a cheep digital AMPERE indicator ( gauge ) . Install a shunt in fuel pump negative lead, between Pump and your ground point. connect low power gauge wires from shunt to meter ( any chinese 3 digit voltmeter will work, as long as it has millivolt or so resolution.
Keeping an eye on actual running fuel pump current could give you some indication of impending failure..... other than that- maybe try a different brand: AEM 340 ?
please keep this thread going what steps you take, and what final resolution.

 

Just as information here, Walbro pumps are owned by TI Automotive and now (for several years now) say TI Automotive on the box. If your buying pumps that say Walbro on the box, they could be imitation. Walbro has been around for 70ish years and have been counterfeited a lot. I’m sure there could still be TI pumps out there in Walbro boxes, because they made a zillion of them. I’m only raising caution here on what’s out there. I’ve bought a few TI pumps and never had an issue. I got a Walbro through TanksInc and is also been a good pump.
Grounding…stranded copper wiring is 30 times more conductive than mild steel. If your grounding the pump to a frame member…run a 12 gauge isolated stranded copper ground wire exclusively for the pump, to the battery ground, or maybe a ground block up front (or rear, if your battery is in the rear) that’s close to the battery. There’s not a lot of steel in a Corvette, so shoot for a quality ground with copper wire at the battery.
In the world of NASCAR Cup racing, we determined over 30 years ago that the cars picked up substantial peak RPM’s, by running a dedicated 1/0 copper ground cable from the battery in the rear, to the engine block…VS. grounding the battery to the chassis back by the battery. The distributor and ignition boxes were grounded to the block…major improvement in ignition spark amperage. Added 4 pounds of weight, but found performance. Definitely worth the trade off.
Maybe this will help your situation here, in a vehicle never designed for an in-tank electric pump.

 

Thank you for the replies. I'll investigate the old pump and see what I can find. I'm planning to replace with an AEM 340, as well as running a dedicated grounding block from the negative battery terminal to see if that helps resolve it, unless I find something else from my investigation of the old pump. Will keep ya'll posted.

 

I am in the market for a 255lph pump and threads like his are so frustrating.

I hate to spend money on fake trash.

 

Only buy from a known genuine dealer. Never trust the eBay's or Amazon's

 

When I go to the Tanks Incorporated website the don't list any "3 series" walbro pumps anywhere. Even tried using their search bar.

Best as I can tell from my research I need a GSS342 configuration to do a drop in installation in my Ford Ranger tank module.


EDIT, nevermind, I found it. The 255 pump is listed as a 4 series pump for whatever reason.

Thanks guys!