I've got a walbro fuel pump that I installed, I reused the factory fuel bucket with no problems. Everything is sealed up nice and tight just like the factory pump was.

Problem is that the car runs great until I get to about a 1/4 of a tank of gas and then the car will die at random. I might just be sitting at a light or crusing down the road and the car will die due to the pump. I can sit on the side of the road with the car off and then restart it after sitting for about 5 mins and then the car will run fine again for a little while longer (less than 5 min) and then it will die again. BUT if I got put more gas in my car the pump works flawlessly! So I am thinking overheating? It's got to be overheating because it only does it when there is a low amount of gas in the car which means the pump is recirculating the hot gas over and over again. But when there is a lot of gas in the car it's not recycling hot gas anymore as bad.

Any ideas on how I can fix this? I am thinking about removing the pump from the bucket to see if that helps. This is my SECOND fuel pump that has done this. I sent back my other walbro that I just got a month again and the company sent me a new one. I just installed this brand new one today and it's doing the same exact thing as the other one did.

 

I would say it is not the pump then, if two were doing the same thing. I think you have something put together wrong, like the bucket. I run mine without the bucket, but I never let my tank get down to a 1/4.

 

Sounds like you are using a universal pump without the venturi & you are leaving it inside the bucket. When fuel level is low, the bucket does not always fill fast enough to keep the pump covered.

I would recommend a pump kit made specifically for your vehicle.

 

Well whats weird is that I hooked a fuel pressure gauge up to the car and let the car sit and idle in my driveway, and while its sitting there idling the fuel pressure will be at a steady 44psi, then after idling for about 5 mins the pressure will drop down to about 20psi and then slowly keep going down after that until the car just dies. I keep thinking it's got to be some sort of overheating issue because why is it that when the car dies I have to let it sit for like 5 min before I can restart?

I am probably going to try running it without the bucket today and see if that helps but I would still like some more opinions because the stock pump works just fine while in the bucket so why not this pump?

I agree with you about it not being the pump because this is pump #2. How might you suggest I have the bucket put together wrong?

What exactly do you mean about the venturi? Can I tell what kind it is by looking at the pump? Like if a posted a picture or something?

 

I guess I should ask..... what year car are you working on? On the '99 up cars, there is a second small tube connected to the factory pump. Does yours have 2 hoses on it or just 1? If you have an LT1, we have other issues....

 

Oh ok yeah the car I am currently working on is a 97 LT1

 

You have no Venturi..... sorry for the confusion. Most people here are LS1 guys.

On the LT1, did you put the return line back into the bucket? This keeps the bucket full of fuel & cools the pump.

If you get any pictures, please post them.

 

Well the LT1 is just a buddies car, but I wasn't aware of the venturi on my LS1 either so now I know Also yes the return line has been put back on. What would you like me to take pics of and I will get them up asap.

 

I have been fighting the exact same problem for over 3 months now.

https://ls1tech.com/forums/fueling-injection/701761-overheated-fuel-pump.html

I had similar results with the Walbro pump. It would die at idle or any low RPM application. I would let it sit and it would operate normally for a period of time. I also filled up with gas and it would work again. So I also assumed that it was overheated gas. But later on it would do it when then tank was 3/4 full as well.

So what i've done, I bought a hotwire kit from Nasty. It is a direct line from the battery that guarantees that the pump is getting the proper voltage. It is a nice kit, it plugs right in to the factory wiring. It alone did not work. It still behaved the same way.

I figured that the pump may have been damaged, possibly from overheating. So yesterday I dropped the tank again and replaced the Walbro unit. It ran fine for one run. I will report in in a few days and let you know if the problem has been fixed. I need to get a few consecutive hours on the car in the 90 deg heat before I consider cured.

 

Yeah I just received a brand new granatelli fuel pump kit today that I am going to try out and see if it works better. It has the walbro pump and I actually just found out that the pump I had bought was some cheap imitation pump that someone seller told me was a GENUINE Walbro on ebay So I hopefully having a genuine walbro pump will now cure the problem. I will post back in a few days and let you guys know the results.

Also this pump I got is definitely a new design from the walbro pump that I bought 4 years ago. It looks like they changed it so that the inlet tube is offest now instead of in the center of the pump so now the ribs dont have to be cut out of the bucket. Mine installed without any issues at all. Hopefully this one will run right.

 

Well the new pump works perfect. Got a genuine Walbro installed and I drove the car around all day and drove it well below the EMPTY line on my gas gauge and it ran with no problems. Didn't die on me once. So anyone else having these issues, make sure you got yourself a GENUINE walbro pump, not a cheap knock off like some douche bag sold me.

 

Who was the Ebay seller so nobody else falls for the same crap.

 

bump for more info.

 

I would be wary of buying one on ebay. I have heard that there is now a Chinese knockoff being sold that is of the usual low quality of most Chinese products. I would buy one from a reputable company, preferably a sponsor.

 

Sorry for the delay. The username of the person that I bought it from is now actually saying that he is no longer a registered user. So it looks like he has had a lot of complaints and got shut down. He got me pretty good because his listing said walbro pump in the title and in the description but then I later found out it was a "LIKE WALBRO" pump

The one I ended up getting was the granatelli one from summit racing. This one fits PERFECT in the factory bucket because it looks like Walbro changed their pump design and they now have the inlet offset rather than in the middle like the old style. In any case this pump is working FLAWLESSLY.

Only problem that I was having after install was that the fuel pressure wasn't holding after prime and it would drop off all the way to zero psi. Turned out that the plastic tube that goes from the pump outlet to the quick connect fitting on the sender was garbage. I had a clamp on there tight as can be but some how pressure was still leaking out. There were no cracks in the hose itself so appearantly it was leaking out where the clamp was. In any case I ended up just getting some 5/16" rubber fuel hose and clamped it down on both ends now the pressure holds stronger than ever. I would definitely recommend that ANYONE having a fuel pressure not holding problem that they check that hose and replace it no matter HOW good it looks because mine looked like it was perfect but it turned out to be the problem after all.

 

DSMkilla,
Thanks for the feedback concerning the pump brand. I see far too many threads of "Walbro" failures that actually are inferior junk. Unfortunately, few actually come back to set the record straight.

As for your rubber hose replacement, I hope you used one intended for intank use..... this hose is different than fuel injection hose.

To be fair, I'm not claiming Walbro to be perfect either, but I have yet to have a failure from one of my customers.

Koolaid_kid,
I appreciate your suggestion to use the sponsors here. Far too often, I get calls from people asking for pump tech suport help AFTER they spent their money elsewhere. Sometimes saving $5 can cause 5 hours grief.... you often get what you pay for.

 

You are welcome. Most sponsors spend time here solving problems; you should receive the reward. I may have to contact you soon; I am having fuel pressure issues myself. If it is not the filter (fingers crossed) then it is the 255lph fuel pump.
I hope not, because I just filled the tank up right before I discovered the problem this afternoon.

 

Well it looks more durable than the crap rubber hoses that are already in the tank for the return line and vent tube etc. It was goodyear fuel injection hose, black with the white threads going thru it. I don't see how it would matter, it's obviously designed to hold fuel hence the reason calling it fuel hose so I don't think they would design a fuel hose that was meant to deterorate. Oh well it's becoming a monthly ritual to remove the tank anyways so I will just keep an eye on it.

 

It does matter because regular fuel injection hose is rated for constant fuel contact on the inside of the hose only. You now have fuel on the outside of the hose when it is in the tank. This constant submersion can result in the outside part of the hose swelling & turning to goo. At that point the braiding no longer supports the hose & the internal hose ruptures.

The vent & return lines & are of lesser quality as they do not support any pressure.

Good intank hose can cost $20-25/ft. & is special order at most parts stores. I use it anywhere I have to run rubber internally. I now build every kit possible with teflon hoses for durability reasons as the latest fuel additives tend to harden even the good rubber hoses after a while.

 

Great info, should sticky it! I'll atleast save it to word. Thanks for the info!