Write-Up: Walbro 255 lph Fuel Pump - Series I

Mine was out at 83,000 (fuel level sensor). I bet it had been out by a long time by then.

I don't recall AA mentioning a pump failure. Or many others for that matter. Unless anyone objects I'm going to treat it as a reliable part and just do the fuel level sensor. Wouldn't mind getting a couple spare strainers though just for the heck of it. I'm sure they're too cheap not to have a couple sitting around.

For what its worth Jack, mine failed at 210,000K. The symptom I encountered just before it failed, was that the engine would cut out while coasting, but putting the car in neutral and re-starting got me back in drive. It did that two times before it failed the third time. I attributed the first two times to the weather as the stalls occured in the winter. I was planning to replace the fuel pump at the beginning of the spring, just before it died on me, but I didn't get around to it in time. Even though yours might have some life in it, I would replace it at the same time.

If they weren't so bloody expensive I'd be inclined to agree with BMD and do it for preventive maintenance.
But if it's not showing any signs of failure I would give it some more miles.
But hell if you got the cash put in a new one while your there. I wouldn't want to be the reason you got stranded on a cold dark night sometime this winter.
I wouldn't bother with extra strainers either. Do you really think you'll pull the pump sometime in the near future to replace just a strainer. I don't think so.
The next time your in there will be to put in a new fuel pump and strainer hopefully before it completely fails on you.
As has already been mentioned they usually give you some notice before complete failure. Not always though.!!!!!!!

It's getting to be new computer time again, so I don't want to replace the fuel pump unless it's going to die within 20,000 miles. Seems unlikely based on what I'm reading. Thanks everyone.

I got around to replacing my Walbro pump with the Racetronix pump today so here's a write-up supplement. After having to do a lot of research and comparison without being able to look at the inside of my stock pump assembly, I made sure to take lots of pictures of it this time.



there's the complete internal harness after I pinned in a new level sensor and the new Racetronix fuel pump harness (it comes with a connector that fits the W-bodies so you can't use it on a riv)


there's the bucket off my stock assembly (obviously removed from the top)

there's the piece that the venturi line feeds. This part sits directly atop the strainer sock on the bottom of the bucket...

...which is pictured below





there's the top part of the assembly pretty much naked


that's how the pump itself looks fully seated at the bottom


there's the racetronix getting put in


That's the barbed fitting that the main corrugated feed hose slips onto. Reusing this corrugated hose is not an option unless you want to hack it up with clamps. It can be bought from the vendors. My racetronix pump came with it.




That's how it'll look plummed, just like stock.
The plastic venturi feed line didn't fit tightly onto the new pump fitting after it had been beat up from being twice removed and unfortunately It's not as easily replacable as the main hose so I nipped off the end of it and with a fresh end, it fit tightly onto the pump fitting and there is more than enough length on it to cut that ~3/4" of it off.






and there it is reassembled and ready to go back in

Getting the locking ring off was a piece of cake after doing this already several months ago so I'll definitely say it was a very good idea to use antiseize or something on the locking ring. I used petrolium jelly.

btw I used the level sensor off a new 98-00 gtp pump assembly (Delphi part) and it looks and works fine. Use your original float obviously.

I did test this afterwards to make sure my fuel pressure issue was corrected. The pump does, in fact, retain fuel pressure when it's not running now. I hooked up my fuel pressure gauge at the rail fitting and turned the igition on, watched the fuel pressure come, then once the pump ended its prime cycle and shut off, pressure stayed, instead of immediately bleeding off like it was with the walbro and its rigged venturi setup.

That bleeding off of fuel pressure is not harmful in any way except that it makes starts a little less natural and effortless. This is a bigger problem for me than most people because I wait until after the prime cycle to start the engine so my electronic boost gauge can calibrate itsself. If you have a walbro and start the car while its still in its prime cycle, which is what most people naturally do rather than wait, it's not really too noticable.

Thanks for the extra photos and advice about the corrugated hose. Do all walbros do this? Is that why you switched to the racetronix pump?

deekster_caddy wrote:

Do all walbros do this? Is that why you switched to the racetronix pump?

yes and yes

bouth pictures of the bumps still don't look the same as i had in my 96 :S....did they all have diferent bumps??

Neither one of these write ups pertain to the series 1. I dont know how Palermo cory ever got it to work but the pumps are not even close.I ordered the exact same pump that palermo ordered and It cannot fit and will not fit.in any way.
maybe I'm missing something but the new pump has nowhere to moore inside the pump housing.it will just knock about and bash the inside of the housing.
If any one with a series one has managed to get this to work,please let me know how its done.por favor!

... I made a Delrin sleeve for mine to fit....I also ordered the venturi specific one from intense, but then discovered I dint need a venturi, and had to plug it. did I ever post pics? if not I'll have to look for them.

a delrin sleeve? this I gotta see...
How did you modify the walbro to adapt to the oem housing bottom feed hole? I dont see any other way to modify it?If I put my ear to the grindstone I would come up with something but...I'm looking for a quick forMuLA!!!!!!!!!1

Here are a few pics of what I see as a Good mod.I got this one from Intense,$99 bucks.After seeing the oem set up,there is no doubt in my mind that the only fuel set up is a race one.The oem peripherals only make servicing the fuel system harder than it has to be.and pretty weak too!
everyone knows how to remove the oem pump so I wont cover that.

side by side

I cut a slit onto the bottom of the pump.I dont want the filter scruntched up in the bottom of the sump like the oem.It was the point of failure with the original filter.--

Walbro pump --

pump in sump--

side view of pump in sump--

cut 2 slits in side of sump for a circle clamp--

pump in sump all snugged up.not to tight or you will distort the housing.it is necessary to tap lightly with a hammer the circle clamp to flatten it against the outside of the sump.otherwise you will have difficulty inserting into tank.--

how pump looks from inside


Lop the top off the housing to make room for the walbro-


view of the level sensor thingie--


and here she is all snugged up and ready to pump--



after taking her for a test ride,I noticed a huge increase in throttle response.She gained a few HPs for sure.there was a big lull going hard round a corner.this told me that maybe the bottom slit that I cut for the walbro filter was a little too large and fuel sloshed out the bottom leaving the pump starved momentarily.but I am at less than a 1/4 tank so....
electrical hook up was a snap.the pump came with a pigtail that hooked right up the the oem connections.
its a real hassle working with a system that is designed by GM not to be fucked with.a good reason why a race tank is in order.I'll be converting the oem tank into a race tank with AE fitting in the future.I'll have access to the oem service locations but with the conveniance and serviceability of a race set up.

the reason why I did not use the original pump location in the sump for the walbro is because moving the walbro over a little,I cleared a couple of protrusions on the bottom of the sump that would have the walbro sitting higher in the sump than I would have liked.sitting lower the pump sits in more fuel for those low fuel situations.
For the series 1 folks,when ordering the L67 pump from intense,specify a "Non Venturi" type pump.the venturi style pump has a little brass tit on top of the pump that for the series 1 is unessecary

Right I found my pics. Not all of them as some were corrupt.

Pump with new Delrin Sleeve compared to stock pump:


Sleeve slid on: (I haven't plugged the venturi port yet in this pic. SERIES ONE DON'T BUY A VENTURI SPECIFIC ONE!)


More of the sleeve:


I made a tool to pull the new hose onto the barb since it was REALLY REALLY tight:


Attachments with fuel clamps:



Whole assembly:



Thats all I got. As I said a bunch of pics were corrupted. Mine does sit right at the bottom of the container with no issues. The Delrin sleeve slides right against the stock location, and inside that the new pump sits inside its rubber sleeve to absorb vibration. I've run the tank practically dry with this setup with no issues. It performs as stock but with the Walbro pump.


Robo, your cornering prob might be because I *think* the fuel feed on ours also sends some down the 3 rods that have springs around them to keep the canister full. Its our version of the venturi that keeps the canister full on later models. (but I might be wrong, it was ages ago I took this thing apart.)

oohh! I like youre idea better.wished ya woulda posted that before?!
I have three options. one.allways run the tank no less than a 1/4 full. two. close up the slit I made at the bottom and stuff the filter in the sump. I dont like bending up the filter. three.make a t-shirt outa my pump.a face only a mother could love.

YESTERDAY MY FUEL PMP DIE SO I THOUGHT ......I BOUGHT A NEW FUEL PUMP & TRY TO GET INSTALLED COME TO FIND OUT THE PUMP HOLD DOWN HAS RUSTED AWAY & THE CONNECTER IS BAD SO THE PUMPS NOT BAD THE MECHANIC SAY I NEED A NEW TANK OR CAN I BUY THOSE PARTS SOMEBODY HELP ME

WHAT IT IS THE Fuel Sender Cam & WHAT THE Fuel Sender Cam LOCKS INTO ON THE TANK IS RUSTED OUT TRYING TO GET PICTURES

If he's talking about the steel tabs molded into the tank opening,then maybe yeah.a new tank is needed. it is possible to drill a bunch of holes around the circumference of the hole and into the steel ring that holds down the pump,and bolt down the pump.but that would take fabrication and patience 2 things the average mechanic dont have.

waiting for the pics..............

Everythink On Top Is Rusted Out ( Gone )

Oh good God! new tank time.call morads and see if they have a good used one.

What You Think One May $$ Cost $$( About )

Ok Sometime Else Remember I said I Thought The Pump Was Bad Its The Connector To The pump Should Try To Find One With The Pump Or Buy A New One With New Connectors

A used one should cost anywhere between $50 and $75 bucks. You can negotiate cost plus shipping.worth a shot.these things happen.17 year old car.east coast salt.GM should have isolated that area from road debris.But they didnt.gee..big surprise.