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Are these OK? Fuel line adapters for Carter to Edelbrock fuel pump.

Nismobishi

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Hello,
I can not find a Carter 6903 pump in stock anywhere so I went with the Edelbrock 1723 which looks identical and has the same specs except that it is polished and has 3/8 NPT fittings instead of 1/4" NPT fittings.

I had to use a couple of adapters because I could not find the correct fittings that I needed and I was in a hurry to be able to move the car.

For inlet I have the 1/4" NPT barbed fitting adapted with a 1/4" NPT to 3/8" NPT adapter bushing.

For the outlet my fuel line is 5/16" inverted flare that already had an adapter to 1/4" NPT. On top of that I had to add a 1/4" NPT to 3/8" NPT adapter bushing.

So, long story short... 1 adapter on the inlet and 2 adapters on the outlet. All are sealed with Permatex thread sealant. No leaks at all and the car runs great.

On to the big question... Can I leave it like this or should I order the proper fittings so that there are no adapters being used in the long run?

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Your choice... It's functional.. It doesn't leak.. It will work... But if your gonna stress out over the potential for a problem you should probably get the right parts to fix it...

Then again the new "right" parts will probably come from China so are they really any better than the Rube Goldberg repair you currently have??
 
Also, how long are the fuel pump bolts supposed to be? The Edelbrock bolts that came with it are about 1.4" long and the ones that I took out are about 1" long. I went ahead and reused the ones that I took out because I was worried that the other ones might go in too deep. I could definitely feel the bolt coming through the inside when I put my finger through the fuel pump hole. The bolts that I used go into the block maybe about 1/2" by the time they pass through the fuel pump and the gasket. Which bolts sound correct?
 
Either is fine, the longer bolt might help getting things lined up, but since you had no issue getting the shorter bolts started I'd stick with them...

The rule is a 3/8" bolt needs 3/8" of thread engagement... It should have that and more...
 
Thats a bunch of fittings. You should be able to cut that back to one per hole and get what you need. Is the steel tube on the outlet and the hose on the inlet 5/16"? Like Randy said, it does work. One thing I look at is that every fitting in that equation is a restrictor. Yes the hose or tube are a given size but look inside those adaptors. It's a hole smaller than you expect. Its picking fly poo out of pepper, so it may not matter for what you do.
 
Hello ckessel,
Yes, they are both 5/16". 5/16" rubber inlet hose and 5/16" steel flare tube. Both holes on the pump are 3/8" NPT.
 
The only issue I see is the worm clamp on the inlet hose. A spring style clamp would be better. The rubber will relax under the worm style clamp and loosen. A spring style clamp will always maintain correct pressure on the connection.
Mike
 
Next time I'm in SLO, I'll stop by the store I used to work at and see if I can get you either a Weatherhead or Edelman number or two for your fittings. The inlet side to hose I've seen at the local hardware store. Inverted flare though is automotive and industrial.
 
Thanks for the help everyone!
I found the 5/16" inverted flare to 3/8" NPT adapter on Ebay. Its on the way:)

For the barbed fitting, the local ace hardware store has a brass fitting with a 3/8" barb and a 3/8" NPT. Its in a package marketed toward air tools or air hose. That's just a packaging gimmick right? I mean, its not like its made out of a different kind of brass or something. Is there something different about it that would make it not suitable for gasoline?

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Thanks for the help everyone!
I found the 5/16" inverted flare to 3/8" NPT adapter on Ebay. Its on the way:)

For the barbed fitting, the local ace hardware store has a brass fitting with a 3/8" barb and a 3/8" NPT. Its in a package marketed toward air tools or air hose. That's just a packaging gimmick right? I mean, its not like its made out of a different kind of brass or something. Is there something different about it that would make it not suitable for gasoline?

View attachment 1919985

Nope, would work fine.
 
Thanks for the help everyone!
I found the 5/16" inverted flare to 3/8" NPT adapter on Ebay. Its on the way:)

For the barbed fitting, the local ace hardware store has a brass fitting with a 3/8" barb and a 3/8" NPT. Its in a package marketed toward air tools or air hose. That's just a packaging gimmick right? I mean, its not like its made out of a different kind of brass or something. Is there something different about it that would make it not suitable for gasoline?

View attachment 1919985
What gives you that idea?
Mike
 
I need to get a better fuel pump myself.. would have had to find that eventually :) Mancini has a bolt together pump but looks cheaply made.. 5-6psi though instead of 8+, might try it
 
It looks like you put thread sealant on the adapters.
Shouldn't be necessary or recommended.
 
I need to get a better fuel pump myself.. would have had to find that eventually :) Mancini has a bolt together pump but looks cheaply made.. 5-6psi though instead of 8+, might try it
I called Mancinni and talked to him about his cheaper pumps when I was looking for a Carter 6903. He said they wouldn't really be that great for my 440 with a mild cam and 2 Edelbrock carbs and that if I couldn't find a Carter then I should get the Edelbrock or the Holly. I went with the Edelbrock 1723 as I believe it is that same as the Carter 6903. Just about the same specs but just has a polished housing and bigger inlet and outlet holes. The housing looks identical to the Carter housing. They are from the same mold number 12. The Edelbrock even has the flat recessed logo area where Carter puts their name.
 
I called Mancinni and talked to him about his cheaper pumps when I was looking for a Carter 6903. He said they wouldn't really be that great for my 440 with a mild cam and 2 Edelbrock carbs and that if I couldn't find a Carter then I should get the Edelbrock or the Holly. I went with the Edelbrock 1723 as I believe it is that same as the Carter 6903. Just about the same specs but just has a polished housing and bigger inlet and outlet holes. The housing looks identical to the Carter housing. They are from the same mold number 12. The Edelbrock even has the flat recessed logo area where Carter puts their name.

did you need a regulator with the 1723?
 
What gives you that idea?
Mike
Nothing really, LOL. Just that some are labeled as air compressor accessories and some are labeled as plumbing and some are labeled as fuel and chemicals... I'm not sure why they just don't list all of the uses on the same packages lol. The real kicker is that the ones packaged like this for air are usually around $3 and the ones in the plumbing department are usually around $6, LOL!
 
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