So I am running a Walbro 255 with the 12v mod done, and the pump is LOUD. I mean no louder than other Walbros I have heard, but the interesting thing is that if I do some side to side fuel sloshing by sawing the wheel on the highway, the thing gets almost dead quiet. This is with just over 1/4 tank, so maybe I am uncovering the pickup? I would not think so, but what else would explain it getting quiet? I think I'm going to get a Denso, this pump just kills the whole luxury interior feel with its incessant whining.

 

Walbro's are just loud. You can't escape that. I'd rather do an inline pump over putting in a Walbro for a daily + power car.

 

Walbros have metal gears, OEM's are plastic. Keep your tank full if you don't want to hear it. Or maybe wrap the gas tank in dynamat, I bet that would help.

 

If you google it, you'll find lots of reports about the excess noise from Walbros. I was able to muffle it substantially with just an old moving blanket stuffed back in/around/over the gas tank. I can still hear it if I listen for it, but it's totally livable now.

 

Thanks guys. The point was not that it was loud. I have run Walbros before and I know they whine, but this one actually gets quiet when the fuel sloshes in the tank. I dont know why, but it does. That is all I was saying. Just an interesting observation I guess you could call it.

I think I notice this one whining more since it is right behind the back seat as opposed to under the car way at the back like my Mustangs were.

 

I have yet to run a full tank. I will try that and see if it makes a difference.

 

My walbro does the same thing. Makes noise but when I make a hard turn and the fuel moves around, you hear it get quiet and gets back loud when it settles.

 

Isn't that strange? I wonder why it does that?

 

Probably has nothing to do with your concern but I found that my Walbro's pressure relief valve was leaking ALL THE TIME.

Key on engine off (12volt mod) it was leaking. Engine running, which is actually less pressure than with the engine off, it was leaking.

Put a small srew in the hole and it has held so far. Have checked it a few times. Still just as noisy though.

KC

 

Thats why I chose the Denso, I have yet to install it though.

 

Where is the valve you are talking about on the pump, and how did you figure out it was leaking?

 

you guys think the walbro intank is loud , you should hear my bosch 044 inline after driving for say 30 mins or so .. sounds like a muted coffee grinder and thats after its wrapped with insulation

 

mines doesn't bothers me at all and i don't even have a radio.

 

It is the small hole right next to the outlet of the pump, where the hose connects. You can see the spring.

I took out the back seat, removed the access cover for the pump and turned on the key. Gas was shooting out of the hole, about a 2 inch fountain. When I pinched the small rubber hose to simulate a pressure increase, the fountain grew to about 8 inches or so.

KC

 

I would bet that the pump gets quieter when turning because fuel sloshes around and fills up the sump where the pump is sitting and covers it. Then driving straight the pump may flow enough to keep the sump level low. That would be my best guess.