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-   -   Fuel pump loud (https://67-72chevytrucks.com/vboard/showthread.php?t=577682)

BR3W CITY 04-27-2013 06:43 PM

Fuel pump loud
 
So I took the truck back out on the road for the first time this year today, and all went well, tho I did notice some noise from the fuel pump at one point.

My fuel setup used to be a 255 and earls filter, and has always seemed fine. At this point it was a combination of -8 and -6 coming to some 3/8 hard lime.

Just this year, I switched the -6 out for -8 from tank to hard line, and changed out the fuel pump bracket to sit about 3/4" higher and be a bit more out of site.

On the drive, we heard a loud mechanical wine, much harsher than the usual "fish tank" motor sound the pump usually makes. The pump was not hot to the touch, and the noise only changed slightly when revving or idling. We checked our tank, which was about 1/2 full, maybe a tad less.

We drove to the nearest gas station about 1.5 miles away, and when we pulled in, the noise had gone completely back to normal (no fuel added yet).
Put more gas in it, just to have a fresh tank, and have heard to noise since...

So what do you think? A fluke one the first run, or maybe just some air in the line....or something more nefarious? I'd hate to think the fuel pump was dying already. The pump is a few inches above the sump, but it's worked fine and I was told by the rep' that the draw was not too much for the pump. Hmmmm

Kim57 04-28-2013 12:33 AM

Re: Fuel pump loud
 
This is just me thinking out loud but liquid likes to find level. If the pump was above the level in the tank I would think it has to work harder to pull the fuel up and then push it forward. Once you filled up the fuel was probably above the pump so it didn't have to work as hard. Have no idea why it got quiet before the fill up though.
Kim

BR3W CITY 04-29-2013 12:39 AM

Re: Fuel pump loud
 
That was my initial though, but I've run essentially the same setup for over a year and 6-8k miles without a hiccup. When I was choosing my pump I found a large question and answer list from a Walborough rep on a rally car build; the said that their pumps could handle about 6-10" of vertical lead and up to about 24" of run before the pump (max).

I took it out again last night and did a 20 minute cross town run in the cooler weather, no signs of extra noise and the performance seems fine.

Wasted Income 04-29-2013 11:02 AM

Re: Fuel pump loud
 
With a Walbro 255, it's just a matter of time until it pukes. They are junk.

A few years ago mine got real loud, and it would barely idle at a stop light. Done. Only had 2-3 years on it.

Went to a Bosch 044 and never looked back.

BR3W CITY 04-29-2013 12:45 PM

Re: Fuel pump loud
 
Was there something about your setup that put strain on it (i.e. a little bit of a rise like I have), or did it just kinda die?

I guess my concern would be, would the same thing happen with another (read, more expensive) pump?

Wasted Income 04-29-2013 01:49 PM

Re: Fuel pump loud
 
Strain?....other than the fact it was feeding ~500 rwhp thru a -6 feed line? lol.

It was frame rail mounted, that's about all I can think of.

HOWEVER, the Bosch I replaced it with was feeding the same engine, thru the same fuel system, and mounted in the same location and lived quite a bit longer.

Mine is not an isolated case...I know a handful of guys with swaps around me who've had Walbro's bite it.

ChevyCruizer 04-29-2013 02:58 PM

Re: Fuel pump loud
 
1 Attachment(s)
good thread here, if you dont mind the fact that its in a miata, and the language.

look at the size differance

Wasted Income 04-29-2013 03:05 PM

Re: Fuel pump loud
 
LOL, I've never met a miata guy with a mouth like that....wait...wut?

He's right though...the 044 is a bad mo-fo, but it is quite a bit louder than the Walbro. I think it's even louder than my Fuelab pump, lol

BR3W CITY 04-29-2013 07:01 PM

Re: Fuel pump loud
 
Do you have a pic of how/where your is mounted in relation to the sump/pickup?
For reference, mine looks to be about 7.5" above the sump, I might be able to jack the tank up 2 or so inches if it comes to that.
http://i112.photobucket.com/albums/n...ps19594336.jpg

Clyde65 04-30-2013 08:34 AM

Re: Fuel pump loud
 
BR3wCity,

Sorry to hear your troubles, here is what I have, I have a Pierburg pump and I dont think it is loud at all. I hear it when I first turn the key, then nothing. although I only have a stock motor basically, this will drive a 500HP motor.

Good luck brother

http://www.turnkeyenginesupply.com/c...l-System-Kits/

yes it is expensive, but your truck is worth it!

Wasted Income 04-30-2013 10:11 AM

Re: Fuel pump loud
 
My Walbro/Bosch were at a similar height in relation to the tank (in the frame rail).

My fuelab is mounted to the side of my fuel tank. I don't have a measurement, but you can get a feel for it in these pics.

http://i235.photobucket.com/albums/e...ps8d2b1bcf.jpg

http://i235.photobucket.com/albums/e...ps93ccd351.jpg

ChevyCruizer 04-30-2013 03:18 PM

Re: Fuel pump loud
 
I like the height of WastedIncome's pump in his pictures above. Just figure the lower the better, without having it ripped off my those pesky reflective lane dividers, in my case at least. LOL

Mine is still coming together but I took the standard rear mounted aluminum tank that is usually mounted to the bottom frame rail and set the tank down on the top, raising it several inches. Still have to run the fuel system but I will try and keep the pump as low as possible.

BR3W CITY 04-30-2013 07:36 PM

Re: Fuel pump loud
 
Thanks guys. Its been good the past few days on small cruises, tho I'm still over 1/2 tank of gas, we'll see if it comes back when it gets a bit lower.

I might be able to switch out a couple fittings and put my pump directly off a 90* on the sump, pointing the pump vertical, but putting the lowest point about even with the sump.


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