Fuel Pump?

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Poodlehead

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The problem with an American made A/C Delco pump is it will have been made long before the rubber parts were made with ethanol compatible components. Not to mention A/C Delco today is a not the same as A/C Delco of 30 years ago.

I’m a believer in keeping your “GM vehicle all GM” but it’s not the same GM.

As far as I know, Airtex and Carter are still American. Maybe I’m wrong.
Good point about finding a NOS pump and the rubber being shot. I never thought about it, thanks!

I was reading other posts and people were bashing Airtex... I guess part of it might just be luck of the draw... Thanks again!
 

HotWheelsBurban

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Back in the day, the AC Delco pump number was 40987 for the two line, and 41216 for the three line. Sold enough of them to be able to remember those numbers all these years later.... Installed a few too! Once on the side of I-45 on the way to DFW for a swap meet. Used to keep the longer bolt for holding the pushrod up, in the top tray of the toolbox..... If you knew what you were doing, this fuel pump swap out could be done in less than an hour. Not any more... newer trucks, ya gotta drop the tank!
 

Poodlehead

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Thank you for the PNs. It is very easy to change.

The truck surges when accelerating so since it's is so old I'm thinking about dropping each tank, replacing the filter socks, and inline filters too. Any other suggestions are appreciated.
 

75gmck25

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I found that my rubber lines had exterior cracks and were breaking down inside, and it seemed that the pump might be sucking air instead of fuel. I replaced all the rubber lines with newer ones that are more ethanol resistant. There are a lot of short rubber lines on a squarebody with dual tanks.

For best results, use modern SAE J30R7 rubber fuel line for a carburetor, and J30R9 high pressure line if you have EFI. I bought it from an Amazon vendor because it was too expensive by the foot at the parts store.
 

Poodlehead

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Replacing all those little lines is an excellent idea, especially if I drop the tanks and replace the filter socks.

Do you know what size hose I need to order, 5/16" ? Also, would you know what size the line is that the filter sock goes on? I'd rather have parts lined up once I get started...

FWIW - I did replace the 2 filler and vent hoses on each side a year or two ago because they leaked when I filled up. Why I didn't do more is beyond me...

Thank you!
 

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Replacing all those little lines is an excellent idea, especially if I drop the tanks and replace the filter socks.

Do you know what size hose I need to order, 5/16" ? Also, would you know what size the line is that the filter sock goes on? I'd rather have parts lined up once I get started...

FWIW - I did replace the 2 filler and vent hoses on each side a year or two ago because they leaked when I filled up. Why I didn't do more is beyond me...

Thank you!
3/8" for the feed and 5/16" for the return. 1/4" for the vent
 

Matt69olds

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Good point about finding a NOS pump and the rubber being shot. I never thought about it, thanks!

I was reading other posts and people were bashing Airtex... I guess part of it might just be luck of the draw... Thanks again!

It’s been years since I bought a Airtex pump. It would not surprise me to learn they are outsourced and junk today.
 

texasmike

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Back in the day, the AC Delco pump number was 40987 for the two line, and 41216 for the three line. Sold enough of them to be able to remember those numbers all these years later.... Installed a few too! Once on the side of I-45 on the way to DFW for a swap meet. Used to keep the longer bolt for holding the pushrod up, in the top tray of the toolbox..... If you knew what you were doing, this fuel pump swap out could be done i
Back in the day, the AC Delco pump number was 40987 for the two line, and 41216 for the three line. Sold enough of them to be able to remember those numbers all these years later.... Installed a few too! Once on the side of I-45 on the way to DFW for a swap meet. Used to keep the longer bolt for holding the pushrod up, in the top tray of the toolbox..... If you knew what you were doing, this fuel pump swap out could be done in less than an hour. Not any more... newer trucks, ya gotta drop the tank!

I'm replacing my 2 line mechanical fuel pump on my 77 C10 stock truck. I'd like to use a US made AC Delco pump, but research shows they are no longer available. Would someone please tell me what the Delco P/N is in case I can find a NOS replacement? If I can't get a real Delco pump, research shows Carter brand would be a decent substitute. Would someone please confirm, recommend another mfg, and/or provide mfg part numbers?

I've owned my truck for 44 years so I'm thinking I should drop both tanks and replace the filter/sock in each tank before doing the pump. Rock Auto shows 5/16" and 3/8" size socks. Would anyone know which size filter sock I need?

I'd like to do this right the first time...
TIA,
Pat
I'm not sure if this thread is still working but I thought I would give it a try. Summit lists two pumps for my 3 line stock '84 305ci with Q-jet. The first one is a Carter Muscle Car Pump M6626 for $29.99 and the second one is a Delphi pump MF002-11B1 for $16.99. A close look at the Delphi shows the same number on it, M6626, as the Carter. My concern is not price but with the specs. The Carter shows 7.5-9 psi and the Delphi just shows (stock) for the pressure. What do you folks think? Even though replacing the pump is not a difficult job, I would still rather do it just once. Thanks.
 

Attachments

  • Screenshot 2024-02-20 at 17-12-03 1984 CHEVROLET C10 Carter M6626 Carter Muscle Car Mechanical...png
    Screenshot 2024-02-20 at 17-12-03 1984 CHEVROLET C10 Carter M6626 Carter Muscle Car Mechanical...png
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  • Screenshot 2024-02-20 at 17-12-53 1984 CHEVROLET C10 Delphi MF0002-11B1 Delphi Mechanical Fuel...png
    Screenshot 2024-02-20 at 17-12-53 1984 CHEVROLET C10 Delphi MF0002-11B1 Delphi Mechanical Fuel...png
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Octane

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I put two Napa MF 0002 fuelpumps on my truck.In December,then in February.Very low mile failure.Unless I drive truck almost every day,I crank it over for 20 seconds and pump it 20 times,estimated.Everyday drive? Fires right up.Changed pumps,lines.Rebuilt carb.Used fifferent filters.The truck as far as I know has always done this.I got it from original family.1977 K10,350cid and a qjet.I just run with it...
 

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I'm not sure if this thread is still working but I thought I would give it a try. Summit lists two pumps for my 3 line stock '84 305ci with Q-jet. The first one is a Carter Muscle Car Pump M6626 for $29.99 and the second one is a Delphi pump MF002-11B1 for $16.99. A close look at the Delphi shows the same number on it, M6626, as the Carter. My concern is not price but with the specs. The Carter shows 7.5-9 psi and the Delphi just shows (stock) for the pressure. What do you folks think? Even though replacing the pump is not a difficult job, I would still rather do it just once. Thanks.
the carter pump is going to be useful where you NEED increased pressure (maybe some double pumper holleys or something?) and the accompanying flow. stock means the pump will work to stock spec which was probably somewherre between 5 and 10.

An edelbrock pump is set to output at the ideal pressure for an edelbrock carb. They dont like too much pressure
 

Ricko1966

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I put two Napa MF 0002 fuelpumps on my truck.In December,then in February.Very low mile failure.Unless I drive truck almost every day,I crank it over for 20 seconds and pump it 20 times,estimated.Everyday drive? Fires right up.Changed pumps,lines.Rebuilt carb.Used fifferent filters.The truck as far as I know has always done this.I got it from original family.1977 K10,350cid and a qjet.I just run with it...
Put an original needle and seat back in the carbureator,if you don't have the original type fuel filter,get one. And make sure the plug wells don't leak here's the deal original needle and seat the fuel level had to be 1/2 Inch or so to siphon fuel back out of the bowl. 90 percent of replacement needle and seats have windows in them at the duel well floor,so they can siphon the bowl dry. 3 line pumps got a different fuel filter,with a check valve because a 3 line doesn't have a check valve on the third line so they will allow fuel to siphon from the float bowl. Drip free plug wells and no longer a path for fuel to siphon from the bowl your truck should start right up days after it was last run.
 

Ricko1966

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Not too sure a fuel pump will cause it. Yes, there should be check valves in both the fuel filter and pump however neither could drain the float bowl. If the truck started right away, then quit I would agree with that but do check the pressure and volume anyway. Never want to say never.

Before first start in the morning check the accelerator pump for fuel. There should be enough fuel in the bowl for 3-4 or so good squirts. If only 1, the bowl is draining or leaking.

edit..... could be 2 issues, carb leak and fuel delivery. Need to check both.
You forget about the all too common windowed needle and seat that comes in Damm near every kit or rebuilt q jet these days. With the windowed needle and seat the fuel inlet is at the fuel well bottom,instead of 1/2 an inch up,they will allow the fuel bowl to siphon dry if the needle even has a seep
 

Octane

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Put an original needle and seat back in the carbureator,if you don't have the original type fuel filter,get one. And make sure the plug wells don't leak here's the deal original needle and seat the fuel level had to be 1/2 Inch or so to siphon fuel back out of the bowl. 90 percent of replacement needle and seats have windows in them at the duel well floor,so they can siphon the bowl dry. 3 line pumps got a different fuel filter,with a check valve because a 3 line doesn't have a check valve on the third line so they will allow fuel to siphon from the float bowl. Drip free plug wells and no longer a path for fuel to siphon from the bowl your truck should start right up days after it was last run.
Thanks,I'll investigate it further,I used the needle seat window type once,and the original type.So still an issue.The inline carb filter has a rubber check valve.I've used both kinds,with and without.Maybe its seeping into intake just a drip atva time.But I never see a drip in the venturi leaking either.It seems to me it has to be a carb issue.I rebuilt it last time,and sometimes I smell raw fuel intermittently around truck.But only while driving,never while its parked.Sorry,didnt mean to hi jack the thread
 

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