electric fuel pump question
 

no, not my race car... back to my suburban. i am going to put a fuel pickup in the bottom of the tank, and plumb it like my race car with an electric pump and regulator. plan is to put both in rear of vehicle...
here are my questions...
1. with say 7lbs of pressure should i still go through my mechanical pump ?
2. what pump would you guys recommend, remember flow is not as important as a pump that will survive 10-12 hours of continious running (i am going to belle rose straight thru!)

thanks,
captain jack

p.s. if this does not fix it i will have a 1991 suburban with less than 100,000 mile on it, brand new motor, brand new fuel system and absolutley no rust anywhere for sale ... DAMN CHEAP

Re: electric fuel pump question
 

if it were me, i'd use an OEM/Delphi pump in the tank...notice the "oem" part of this, not airtex or another aftermarket piece of...
you ARE still running the stock throttle body efi for the truck, i'm assuming..?

Re: electric fuel pump question
 

I wouldn't use any aftermarket, or parts store replacement pump. Only genuine AC Delco. Btw, 7 psi is way low. 1991 TBI system needs 10 to 14 psi to run well. 12 to 14 preferred, especially for towing.

Re: electric fuel pump question
 

Be careful with the A/C delco stuff.Not the same old A/Cdelco we are used to.Take a look at Walbro or Ractronics they might have something for you

Kevin

Re: electric fuel pump question
 

actually, NAPA sells delphi pumps nowadays...i THINK Car Quest does too..

Re: electric fuel pump question
 

failed to mention for those who did not get in the post back in october converted to carb motor ... q jet 454, th400

thanks... wish i had left pump in tank and added a regulator 5 years ago.

jack

Re: electric fuel pump question
 

Don't know if you have a shop, or not. I made the mistake of installing too many Walbro pumps. Had to pay too many wrecker bills over failed Walbro pumps. I stopped buying that crap, and out of my pocket bought AC Delco pumps to replace them. I have had no comebacks with OEM plumps. Walbro was OEM for Chrysler, don't know if they still are. Chrysler had way too many pump failures also. From past experiences at my shop, I would never trust or recommend a Walbro pump.

Re: electric fuel pump question
 

Delco doesn't make their own pumps,actually Delco makes very few of their own parts. They contract out to suppliers such as Carter,Raybestos,National, BCA etc for many parts and get a lot of "mileage" out of marketing them under the AC Delco name. I have been in the parts business for more than 25 years and had managed an AC Delco distributorship for almost 10 years,before moving to NAPA.

Re: electric fuel pump question
 

I didn't buy AC pumps from parts stores, I ordered pumps from the GM dealer. Ford pumps from the Ford dealer. I avoided that kind of work on Chrysler products, since the local Chrysler dealership's parts departments did not deliver and their discounts weren't deep enough to make it worth the trouble of someone having to drive across town to pick them up. Ditto International Trucks. Haven't done that kind of work at all for a few years now.

Last pump I bought from NAPA said Walbro right on it. Forget now who's name was on the box. Bendix, Borg Warner, and non-GM AC Delco pumps were re-boxed Walbro also.

Re: electric fuel pump question
 

Yes Walbro had some issues but offered warranty on even out of date products.It was only on a few # s.I have also noticed A/C Delco from the dealer can be different than parts stores??Good info here.I have Walbro pumps in both my cars with no issues.Racetronics also makes some nice stuff.

Kevin

Kevin

Re: electric fuel pump question
 

Warranty doesn't do much to make a customer happy when they call because the car they paid you to fix stops running. I know too many other shop owners with the same experiences and opinions about fuel pumps as I. At least four a month (very busy shop) will give a lot more examples than ownning a couple of vehicles. Hold an original Ford in-tank pump (used to be Bosch) in one hand, and the Walbro replacement in the other. You will see what I mean. The original Ford pump will weigh about twice the Walbro. Plastic is lighter than metal. Don't know who makes Racetronic. Hope it's not Walbro. LOL

Re: electric fuel pump question
 

Ed, was that back in the day when Shell Oil had to admit that one of their gasoline additives was eating up Chrysler pumps? I believe up here it became a warranty issue covered by Shell Oil via Chrysler.

Re: electric fuel pump question
 

Peter, it was a problem up until I stopped doing that kind of work around 2005 or so. Didn't hear anything about Shell. Not many Shell stations here. Sinclair and Sun refineries within 2 miles of my shop. Pretty much all gas sold here locally came out of one of those two refineries.

Re: electric fuel pump question
 

Capt'n Jack -

I seem to remember you having fuel delivery problems with this Suburban before, just not sure how you tried to fix it! Not sure why you'd want to run an in-tank pump with your 454 that's been converted to a Q-jet. You can get a 40 gallon replacement tank and fuel sender/pickup for an 1986 Suburban, which was the last year that the factory used a carb on the light duty trucks. If your block was fitted with a fuel-pump mounting flange, an AC Delco or Holley H/D mechanical pump should work just fine. All the big-block trucks had the 3/8 inch fuel line running down the passenger-side inner frame rail. I've never converted an '87 or newer Suburban to a carb from the TBI, but I've owned a few of each and tried to stay away from most of the non-OEM replacement fuel system parts. The cheaper pumps usually don't give you too much notice when they fail!

Re: electric fuel pump question
 

thanks lew... you actually read my question.
without going back to the october 6 page thread i have tried most every imaginable fix for this... at no apparent issue the truck will go from 8lbs to 2lbs and presents itself like vapor lock. i have rerouted all lines including a new line into tank, had tank off 3 times, 3 mechanical pumps including current holley hi volume with an inline carter booster pump. this issue has been going on for 5 years and ive reached a tipping point... its fixed or sold.

my conclusion was to make a fuel cell out of tank by adding an outlet in bottom of tank and plumb it like a race car with pump & regulator...

i was wondering what aftermarket fuel pump was suggested, of course need one that will see 10-15 hours of continous duty on long tows... flow not as important as durability. also wondered about yes no to go thru mechanical pump.

anyway i almost wished i left tank pump in and just stuck a regulator on it

captain jack

Re: electric fuel pump question
 

I can only imagine how frustrating this has been! I had an '87 Suburban with a 350 and TBI which used to do the same thing. Every so often it would stumble and set the CEL, until I shut the ignition off and then it would be OK until the next time! When I was dropping the tank for the 3rd time, I noticed that the fuel pump holder/pick-up and been modified by some previous owner to use an assembly from a pick-up truck, which at the time must have been easier than spending the $200+ the correct one cost me. After that I had no more problems, at least FUEL problems anyway!

One other "weird" thought - does this fuel pressure/vapor lock happen more frequently in hot weather? I remember reading that some of the folks who used the Suburban to tow the Airstream trailers complained about that same problem. Their solution was to paint the bottom of the fuel tank white to keep road heat away from the fuel! It worked for them!!

Wish I could be more help! My only Suburban problem is the terrible gas mileage @ $3.50 a gallon means I don't go out a lot!:(

Lew

Re: electric fuel pump question
 

Remembering the "rules"
1. all electrical and/or mechanical stuff fails eventually
2. failure occurs at the worst possible moment

So, I would place an electric pump like the Holley Red (etc.--whatever brand you like) down low in the back, and carry a spare already set up for quick replacement. In-tank pumps have been pretty reliable, but the reputation was made in years past when their quality was more certain. I would delete the mechanical pump; it is just in the way. Fabricate a steel line so there is a minimum length of rubber hose down low in the engine compartment.

I had vapor lock problems a long time ago that was caused by proximity of the line to the exhaust system. I re-routed the line from rear to front to cure the problem.

Re: electric fuel pump question
 

There is nothing worse than a problem that cant be figured out. Im frustrated just reading this thread...but I dont think hanging a holley red under the truck is the answer and I wouldnt trust those pumps on a tow vehicle. Obviously if its loosing pressure there is something that is causing it. Is it possible that the gas cap isnt vented and or the vent is plugged? Try removing the gas cap and see if the pressure still drops. I had this problem on my station wagon and it was the gas cap not allowing any air by. It was actually sucking the tank and the lines inside out. I could do a burnout.....stop and lanch it. By the time I got into second it would loose all fuel pressure and run out of gas. Let it sit for 5 minutes and it would fire right back up and run perfect. Just a thought. Any rubber line in the fuel system that is old should be changed as well that way there is no chance that the pump can colapse it.

Re: electric fuel pump question
 

let you guys know next week... longtime racer who had a suburban just gave me a tip and it sounds like a winner...

thanks
captain jack

p.s. bob mulry... happens with cap in glove box :)

Re: electric fuel pump question
 

well here are results...
the tip i thought was winner wasnt, gasline sucking shut at frame at pump was the tip.

i replaced ALL fuel lines including in tank with new line, and new triple reinforced hose with no gap larger than 1/2 inch between lines. i installed a big end red (holley) fuel pump in rear by axle. i headed to belle rose...

i DID need the elcectric pump at most times, but went there and home under power.
not sure why i need all the overkill pump setup, but it works.

thanks to those who chimed in
jack

Re: electric fuel pump question
 

Nothing succeeds like success! I'll file this tip away, who knows, I may need it!:D

Lew

Re: electric fuel pump question
 

Jack, i had a old Ford truck that I towed a lot with here in AZ, in warm weather it gave me all kinds of hot weather driving problems, same deal, I installed larger fuel line, bigger race mechanical fuel pump, put a Holley red pump, and I finally got it to run some what better in AZ weather (110' to 115' weather) The problem ended up being.....the factory air cleaner...I had modified the engine with headers, cam....bla bla....but left the stock air cleaner including the fresh air tube.

Well a friend gave me a much larger air cleaner of a 460 that included all the fresh air system.....problem solved.....I took all the race pumps of and put a stock fuel pump back on it and never had another problem, oh yeah the engine I was using was a 400.