C3 Fuel Pump Questions

[Michael C.]

I've removed the fuel pump from my 69 427/390 due to its leakage. Checking replacement sources I find different appearances. The online images at Zip and Paragon appear the same as the one I removed. These sources claim correct logo and numbers ($145 and $170 respectively). Eckler's image is a pump with an elongated "cylinder" with the tank hose connection. Additionally Eckler's doesn't claim correct logo or number. Their cost is $49.99.

I've included a photo of my pump with an insert of the Eckler version. Can anyone tell me if the short or long "cylinder" is correct?

Also, you'll notice my pump has double-stamped numbers (maybe more). It looks like the last stamping might have been the correct number (40659). It doesn't look like any stamping was of the complete and correct number of 6440659. I'm the original owner, but don't remember the pump being replaced in the past. Any chance this is the original pump? I understand these pumps can't be repaired, so I assume replacement is my only option - correct?

Any reason I should pay the additional $25 for the Paragon version? Actually only a $23 difference because Zip charges $2 for the gasket.

I plan to replace the two rubber hoses related to the pump. Any suggestions there?

Should I spring for the $40 to $45 for a new GF432 filter?

Thanks everyone.
Mike
FuelPump.jpg

[Edward J.]

Re: C3 Fuel Pump Questions

Mike, you should be able to source out a AC Delco pump from a Delco parts supplier. You may have to look up on line to find one near you. The Delco pumps you buy these days are re-boxed parts and likely are are not exactly as the factory pump. they do not stamp the no. on them.

The ones you see from the venders are likely original pumps that have been rebuilt and maybe stamped with the correct no.s that why there so expensive.

[Dick W.]

Re: C3 Fuel Pump Questions

Mike, you should be able to source out a AC Delco pump from a Delco parts supplier. You may have to look up on line to find one near you. The Delco pumps you buy these days are re-boxed parts and likely are are not exactly as the factory pump. they do not stamp the no. on them.

The ones you see from the venders are likely original pumps that have been rebuilt and maybe stamped with the correct no.s that why there so expensive.

The Airtex pumps have the Delco five digit number on them, but without the AC logo. Me for one has never been able to see the stamped number or the AC logo on a big block car, especially with AC. About all you can do from the top side is to verify that "yup, it has a fuel pump"

[Terry M.]

Re: C3 Fuel Pump Questions

Mike, the double stamp is not alarming -- remember they were building these by the thousands back when.

Typically fuel pumps are stamped with the last five numbers of the part number. There is also some letter combination that represents a date code, and David L can help you decode that. I am sure he will post as soon as he sees this. Having that date may help you decide if your pump is original to the car, and thus tell you which configuration to look for.

That style fuel pump can be rebuilt -- but the people who do that are few and far between. Right now my original fuel pump from my LT1 is out for rebuild on the east coast. I will have a report on the success or failure of that operation once I get it back, but I don't expect that will be soon. I am into that car for the long haul.

[Edward J.]

Re: C3 Fuel Pump Questions

Dick,I have never been a Airtex fan, They cannot seem to make a quality fuel pump these days, I would stay with a name you can at least trust. Delco maybe a reboxed part but have installed them on the corvettes I have worked on without problems.

[Joe L.]

Re: C3 Fuel Pump Questions

I've removed the fuel pump from my 69 427/390 due to its leakage. Checking replacement sources I find different appearances. The online images at Zip and Paragon appear the same as the one I removed. These sources claim correct logo and numbers ($145 and $170 respectively). Eckler's image is a pump with an elongated "cylinder" with the tank hose connection. Additionally Eckler's doesn't claim correct logo or number. Their cost is $49.99.

I've included a photo of my pump with an insert of the Eckler version. Can anyone tell me if the short or long "cylinder" is correct?

Also, you'll notice my pump has double-stamped numbers (maybe more). It looks like the last stamping might have been the correct number (40659). It doesn't look like any stamping was of the complete and correct number of 6440659. I'm the original owner, but don't remember the pump being replaced in the past. Any chance this is the original pump? I understand these pumps can't be repaired, so I assume replacement is my only option - correct?

Any reason I should pay the additional $25 for the Paragon version? Actually only a $23 difference because Zip charges $2 for the gasket.

I plan to replace the two rubber hoses related to the pump. Any suggestions there?

Should I spring for the $40 to $45 for a new GF432 filter?

Thanks everyone.
Mike
[ATTACH=CONFIG]45716[/ATTACH]

Mike------


The 40659 is the original fuel pump used for your application. This pump was not available from GM for very long so it's quite possible the one you have is original to the car. You are wise to replace it.

GM or Delco or DELPHI has not manufactured a mechanical type fuel pump for more than 30 years. Any Delco pump you buy today is manufactured by Airtex.

The long inlet valve chamber-type pump replaced the short chamber. Either style will function fine in your application.

If you wish to buy a Delco pump it will be a 40482, the long inlet chamber style.

[Dick W.]

Re: C3 Fuel Pump Questions

Mike------


The 40659 is the original fuel pump used for your application. This pump was not available from GM for very long so it's quite possible the one you have is original to the car. You are wise to replace it.

GM or Delco or DELPHI has not manufactured a mechanical type fuel pump for more than 30 years. Any Delco pump you buy today is manufactured by Airtex.

The long inlet valve chamber-type pump replaced the short chamber. Either style will function fine in your application.

If you wish to buy a Delco pump it will be a 40482, the long inlet chamber style.

I was told that Airtex is the ONLY manufacturer for these old pumps. There are some others but they are configured totally different from the AC's

[Timothy B.]

Re: C3 Fuel Pump Questions

That looks like a original pump to me, I would send it to the west coast to be rebuilt and insist on getting my original core back. The position of the vent holes are what I think make it period correct pump. Have it rebuilt.

[Michael C.]

Re: C3 Fuel Pump Questions

Thanks everyone for the information. I'll go for a low cost functional replacement to get back on the road for now. I'll hang onto the oldie and will appreciate any contact info on a rebuilder.

Any suggestions regarding the hoses and filter?

Mike

[Terry M.]

Re: C3 Fuel Pump Questions

You do need to get hoses that are compatible with modern fuels, unless you have a long term source of alcohol free fuel. There is ink stamp lettering on the hose that indicates it is compatible with modern fuels. I can't remember what it is though. Several people have posted it int he past. You can remove the lettering with a swipe of a rag with lacquer thinner on it. You want that modern hose for safety anyway. I believe it will have a thicker wall and not allow your original clamps to work on it, but that is the price one pays for being safe.

[David L.]

Re: C3 Fuel Pump Questions

A few years ago I started a thread on AC fuel pump date coding as shown in the link below.
I believe that an original 1969 Corvette 427 would be stamped with 7 digits, 2 letters (date code) and 5 numbers (partial AC part number).
What the date code digits on your 40659 pump?

Back in Jan. 1994 at the Cypress Gardens swap meet I bought 4 NOS 68-69 Corvette 327/350 AC fuel pumps ($5 each). There were all stamped "DI 40658" where "D"= April and "I" = 1969". The date code format changed about 1971.

The AC 40659 fuel pump is GM # 6417338.
GM # 6417338 was replaced with GM # 6470106 (AC 40718) in June 1971.

I believe that the 40659 pump has the short neck and the 40718 pump has the long neck.

Dave

https://www.forums.ncrs.org/showthread.php?84774-AC-fuel-pump-date-code-research-data&highlight=fuel+pump+date+code

[Dale C.]

Re: C3 Fuel Pump Questions

Mike, What IMG_1894.jpgdo you think the odds are that we have the same pump with same number? I wonder what the deal is ? Anything is possible I guess. I know it's an old post but I just got to it. Dale