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-   -   Repeatedly blown fuel pump? (https://6066gmcclub.com/showthread.php?t=51806)

Ed Snyder March 25th, 2025 01:50 AM

Re: Repeatedly blown fuel pump?
 
I like to rely on the original mechanical style pumps on my trucks. But I also install an electric pump inline as a backup. It saved my bacon one time in heavy interstate traffic near Seattle. When the mechanical pump failed, fortunately I had the presence of mind to reach down right away and turn the electric pump on. Nobody even honked at me during my slow-down!

lizziemeister'sV6 March 25th, 2025 11:58 AM

Re: Repeatedly blown fuel pump?
 
Ed, do (or did) you have your electric pump plumbed in direct series (same line from tank) with your original mechanical fuel pump or is it fitted into a by-pass line along your frame rail? Thinking - just thinking (I get into a lot of trouble over-thinking) -if you pull fuel thru both pumps constantly do you over-burden both of them? Using the electric pump for back-up is a great idea. :welldone:

sclor March 25th, 2025 10:14 PM

Re: Repeatedly blown fuel pump?
 
Lizzie:
My experience when I was going through the same thing came from disassembling a pump. Found it stopped working from getting rust stuck in the reed valves in the pump. Once the rust was cleaned out, pump resumed working as normal. I ended up changing the steel fuel line from tank to carb. No longer have mechanical pump issues ( and I use ethanol).

Hope that helps.
Regards
Steve
New Orleans

Ed Snyder March 26th, 2025 01:57 AM

Re: Repeatedly blown fuel pump?
 
Quote:

Originally Posted by lizziemeister'sV6 (Post 78741)
Ed, do (or did) you have your electric pump plumbed in direct series (same line from tank) with your original mechanical fuel pump or is it fitted into a by-pass line along your frame rail? Thinking - just thinking (I get into a lot of trouble over-thinking) -if you pull fuel thru both pumps constantly do you over-burden both of them? Using the electric pump for back-up is a great idea. :welldone:

I installed the electric pump in series with the mechanical pump, and never had any issues with premature failures. That particular truck is owned by forum member Clyde in South Carolina now.

jerrspud March 28th, 2025 05:09 PM

Re: Repeatedly blown fuel pump?
 
Quote:

Originally Posted by lizziemeister'sV6 (Post 78741)
Ed, do (or did) you have your electric pump plumbed in direct series (same line from tank) with your original mechanical fuel pump or is it fitted into a by-pass line along your frame rail? Thinking - just thinking (I get into a lot of trouble over-thinking) -if you pull fuel thru both pumps constantly do you over-burden both of them? Using the electric pump for back-up is a great idea. :welldone:

mine is hooked up like that as well. electric behind the seat near the bottom of the tank.

jbgroby March 29th, 2025 01:34 PM

Re: Repeatedly blown fuel pump?
 
Quote:

Originally Posted by kknotts (Post 78654)
Add some marvel mystery oil to the ethanol blend to tone it down and add lubricant for fuel pump and carb parts. Helps motor internals as well.


Would you have a ratio mix, how much MMO to a tank and how often? Thanks
Jake

jbgroby March 29th, 2025 01:38 PM

Re: Repeatedly blown fuel pump?
 
I've went through 3 mechanical pumps in 10 years, I drive her bi-monthly normally either to a show, a cruise in or just to stretch her legs and burn a cigar. I only use Ethanol free (about $4.00 a gallon. The last time I did the swap out about 3 years back I also bought an electric pump, because when this one goes out, I'll make the switch.

kknotts March 29th, 2025 05:05 PM

Re: Repeatedly blown fuel pump?
 
Lizzie meister post here reports 4 oz mmo and 4 oz of sea foam per tank. Sounds about right for ethical blends however I use non ethonal exclusively. Since I am never at or near empty I really only use a “splash” or small pour of each at each fill up. Less when driven regularly during car show season and more in off season when it’s sits and is cranked to keep battery up and fluids brought to temperature and circulated. Don’t always add at every fill up but the last time I changed over to an electric pump I also replaced entire fuel system with new parts including new tank, fuel lines, inline filter and carb kit. She’s a happy girl now!!

James March 29th, 2025 11:04 PM

Re: Repeatedly blown fuel pump?
 
This is what I use: https://www.holley.com/products/fuel...hmMEWTb67-AveV

Oldygoody March 30th, 2025 04:18 PM

Re: Repeatedly blown fuel pump?
 
Thanks for the reply. I got a Mr. Gasket 12s before checking out the reviews which were mostly bad and am reluctant to install it. The Carter mechanical is delivering too much pressure for the Holley 2300 to handle. The float inlet valve has been adjusted to the max but still floods the bowl. Perhaps the older, original and repairable version is the answer.


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