Finally changing the fuel pump

RocketFoot

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I am finally getting around to changing the fuel pump on the engine.  Had to take the oil filter and lower rad hose off to get to the damn bolts but it coming along nicely.  If this don't get her running, I guess a new carb is next.

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Mister 4x4

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Sweet!  Hope that gets it for ya! :thumb:

 

secluff

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Well, while I'm here I might as well........ :whistling:

 

IstoT

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Hmm..I should too...I'm sure that last owner didn't change that and he owned this car 22 years...so it could be real old...but still working..:D

 

RocketFoot

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Ok, so the pump is replaced but still no start.  I pulled the fuel line off the carb and bumped the engine...it squirted like a fire hose!  So there is fuel to the carb.  Engine will start and idle for a few seconds with a little fuel squirted into the carb...so there is spark.  I ain't no mechanic but it seem like I may need a new carb?  Also, when I pulled the line off the carb, it shot the whole way to the firewall like it was pressured up to the carb but couldn't get through!

 

droptop73

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What carb do you have? Is there a sintered bronze filter at the carb inlet? Maybe that's plugged.

 

jpaz

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Try to check the float level in the carb bowls, especially the front one. You could have a bad float or just some crap in there that’s preventing a proper level.

 

RocketFoot

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It's a Holley on there now...not sure what CFM but I can check these things out.  I did spray the shit outta it with carb cleaner and no change!

 

mjlan

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What type of Holley- single inlet with a transfer tube or dual feed?

As another person mentioned, dual feeds (a separate line going to each fuel bowl) originally had a bronze filter underneath the bowl fuel fitting. These can  get plugged up over time.

I can't remember if single feeds had something similar?

Another thing to check is the needle and seat. Its under the adjuster nut on the fuel bowl, if this is stuck it would act like you are describing. try tapping the outside of the bowl in this area with a screwdriver handle.

 

RocketFoot

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It's a single feed Holley.

 

71coop

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Do you have (or have access to) a spare carb you can swap out? Even if you have to fab up temporary fuel lines, you could at least validate if the carb is the issue. 

 

RocketFoot

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Do you have (or have access to) a spare carb you can swap out? Even if you have to fab up temporary fuel lines, you could at least validate if the carb is the issue. 
No, I don't...the symptoms and test results sure do point to a carb issue but like I said, I am not much of a mechanic, LOL!

 

mezell29

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Plugged line or incorrect float as others mentioned. On Holley many can be adjusted externally. Open the float bowl view screws and see if its filling with fuel. It should be right at the bottom of the inspection hole. That will tell you a whole lot. This Holley video may help.

https://www.youtube.com/watch?v=LKEonVeOXco

This will validate if fuel is getting into the carb.

 
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Just a suggestion. The last time I changed a fuel pump it was bad off the shelf. I could not get the engine to run without squirting gas into the carb would not take off. I pulled the pump and used my brake vacuum pump and it would not hold a vacuum so diaphragm was bad out of the box. So I took back to the parts house and took the pump with me to show them it was bad and checked the next one. The one I took off was a Holley that had also gone bad.

 
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