Pay Dues or become a Site Supporter |
|
GMC V6 and V12 Engines Engine repair and rebuilding |
|
Thread Tools |
#21
|
|||
|
|||
Re: 1966 And Later Fuel Pumps
Quote:
The first several that went bad on me, I took apart and they had a small tear in the rubber diaphragm towards the outer edge just inside the body flange. I’m assuming this due to having a hard point/edge that the diaphragm is repeatally flexing against? The pumps still worked with tear, but leaks oil from weep hole and I’m assuming you risk getting gas in the crankcase if you continue driving. Luckily, none have left me stranded. Thanks for sharing. |
#22
|
||||
|
||||
Re: 1966 And Later Fuel Pumps
lost power going up a long hill, pulled the hose off of carb, would still squirt a little gas out. i thought gas gauge was wrong and ran out of gas. a farmer stopped to help, and went and got 5 gal gas. put 4.5 gal in tank, same thing. filled holley carb float bowl from vent hole, got truck running i was able to drive it home. started to run out of fuel in carb again on next hill. backed off of throttle, ran about 1/4 to 1/3 throttle up hill, made it over top of hill. was able to nurse it back, just kept rpm's up and throttle light. i was expecting to have crankcase full of gas but it was ok. changed oil just to make sure and replaced fuel pump.
|
#23
|
|||
|
|||
Re: 1966 And Later Fuel Pumps
Which fuel pumps are rebuildable? I have been getting the NAPA and they seem rebuildable but I am told there is no rebuild kit. The ethanol gas seems to destroy these pumps.
|
#24
|
|||
|
|||
Re: 1966 And Later Fuel Pumps
Quote:
In short, the pump arm stroke (travel) is too great for the (smaller) diameter of the pump. I have proven this by using and hauling non-Ethanol gas on many road trips, and by the type of driving. These pumps last a lot longer when cruising around town at low to mid RPM range. Constant higher RPM is what kills these pumps quicker. I have proven this multiple times by replacing the pump twice within a few hundred miles, running constant highway speed at 3200-3400 RPM while burning non-Ethanol gas (versus driving the same miles back and forth to work through town over a longer period while burning Ethanol gas). My experience is based putting approx 15,000 miles over the last ten years on my ‘62 305. |
#25
|
||||
|
||||
Re: 1966 And Later Fuel Pumps
Another big killer is drying out. If you use your truck then don't use it for extended periods you can get dry cracks in the diaphragm that keep your pump from being able to generate any pull - or push.
__________________
Step by steps: To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. Some people are like slinkys. Not worth much but funny as heck when pushed down stairs. __________________ If the women don't find you handsome, they should at least find you handy. |
#26
|
||||
|
||||
Re: 1966 And Later Fuel Pumps
GMC V6 Fuel Pumps comparison, rebuilding kit and swapping
Quote:
Reading this it got me thinking about rebuilding my old fuel pump from a 1962. It has the straight lever and not the bent lever and secured with 10 bolts. I believe Clarke is correct, that the bent levers were an update to reduce premature fuel pump failure. His thoughts on Ethanol fuel not necessarily being the culprit, but excessive, extended RPMs, made sense. Trying to find a rebuild kit for the GMC unit that could be rebuilt, was a discovery. I found a kit from a company called, Then and Now, #FPA-225, which is for a GMC V6, but it doesn’t have the pressure spring. Cost is $52.50 plus about $12 for the spring. Top Flight also has a kit that with the Pressure Spring that look’s more correct for my pump and runs $100. It’s listed for a 55-66 Corvette so maybe that’s the reason for the high price. Still cheaper to buy a new one but wait… I researched and found the Corvette style pump, with the ten bolts, and it looks like a regular pump for a six cylinder Bel Air. It was cheap, about $30 and it weighed less, but it matched up, so I swapped the lower bowl and changed out the upper Diaphragm and reassembled. I could have just swapped the lever, but chose not to do that. I also purchased the Carter M3955 for comparison. It has the straight lever and is much small and lighter with smaller inlet and outlet holes. Also purchased a Carter crimped style, bent lever, fuel pump M4548 mentioned in the above thread. Lots of tutorials online on how to rebuild a fuel pump and it’s a fun project. But as an alternative to the kit, I just decided to swap out parts from a newer unit. The Carter Electric fuel pump (4070?) I used for many years, is now manufactured overseas. I have been reading about premature failures for these units, and it was suggested to buy NOS with “Made in the U.S.A.” stamped on them.
__________________
1961 GMC Suburban 305A Overdrive 1962 GMC Utility 305D |
The Following 4 Users Say Thank You to Funky61 For This Useful Post: | ||
(August 16th, 2024), jerrspud (September 18th, 2024), Phil (August 17th, 2024), steve pappy (July 6th, 2024) |
#27
|
||||
|
||||
Re: 1966 And Later Fuel Pumps
I will be using this Made in the USA Facet model FAC-40007 in line with the mechanical pump, along with a primer button as mentioned by Ed Synder.
Facet Cylindrical 12v Fuel Pump, 1/4 NPT, 4-5.5 psi Brand: Facet-Purolator For higher fuel volume requirements of engines above about 150 horsepower, the high-performance Facet Cylindrical pumps can deliver. Pumps can also be combined in series or parallel to achieve any required pressure or flow. Facet fuel pumps have low power requirements (about 1 amp at 12 volts) and operate without troublesome seals or diaphragms. Built-in pressure relief means no flooding after shutting down a hot engine. Facet pumps are compatible with gasoline, alcohol blends (up to and including E85), diesel, biodiesel, and fuel additives. Maximum fuel delivery 36 gallons per hour. Maximum pressure 4 to 5.5 psi. Typical flow 23 gallons per hour at 2 psi. 1/4 NPT female ports. Negative ground (12v) only. This pump features an internal 74 micron filter. This pump does not have an anti-siphon valve, so fuel can flow through when the pump is turned off. Facet part number 40007(E)*. This pump can also replace Facet pump numbers 40134 and 40220.
__________________
1961 GMC Suburban 305A Overdrive 1962 GMC Utility 305D |
#28
|
|||
|
|||
Re: 1966 And Later Fuel Pumps
Plan to order this for backup. Looks right for 305E. 1968 Chevy C60 listed with 305E V6 on O'reilly. Truck sat 10 years w/ 6 gal regular 10% ethanol. No fuel flow. 10+ year old pump tested good on bench. Fuel line plugged. Cleared line. Adding inline fuel filter.
|
The Following User Says Thank You to Phil For This Useful Post: | ||
Funky61 (August 16th, 2024) |
#29
|
|||
|
|||
Re: 1966 And Later Fuel Pumps
10+ year old fuel pump works after clearing line. Installed 3/8" filter below pump.
|
Bookmarks |
Thread Tools | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
1966 351E GMC Fuel pumps that may interchange? | Archiver | Previous Forum Posts | 5 | February 7th, 2012 01:04 AM |
Re:637 Fuel Pumps | Archiver | Previous Forum Posts | 0 | January 6th, 2008 01:29 AM |
Re: Fuel pumps | Archiver | Previous Forum Posts | 0 | August 5th, 2007 03:04 AM |
Fuel pumps | Archiver | Previous Forum Posts | 0 | August 4th, 2007 03:09 PM |
Fuel pumps | Archiver | Previous Forum Posts | 0 | February 4th, 2006 09:46 AM |