Cause of surging and loss of power?

[Geff McCarthy]

I asked for help with this problem; my 63 400 4bbl ran fine, but now periodically slows down, idles roughly, then recovers. I was advised to rrebuild the carb, which I have done for the 2nd time. I think my original hypothesis of blocked fuel inlet in the tank, or line, may be correct. When disassembling the Eddy, i found the filter screen at the inlet partly blocked by rubber-like debris. See photo.
So...should i remove and check the sending unit? Can I do this at home with a floor jack and stands?
Plus, the fuel gauge no longer works. However, the instruments were removed and reinstalled during a trans cable replacement. Confusing ,no?

 

[Bee1971]

Those needle and seat screens are part of either a Carter or Edelbrock carb - Bigger question is what are you using for an actual FUEL FILTER before your carb that all that crap is making it that far to your needle and seats ?

What type of rubber fuel hoses are you using also ? Brand of hoses

 

[Geff McCarthy]

Thanks!! standard fuel filter. I pulled it and blew through it and it seemed intact, or not blocked. The tank, sender, fuel pump are all new, but the hose may be original. I agree that the fuel filter is inadequate, tho' the debris might be from the line from the filter to the carb. I suspect the sender filter, or damage to the sender that resulted in the inop gauge, as the cause of low fuel feed. What think ye? Thanks again!

 

[Geff McCarthy]

yes its an Edelbrock 1407, old but very little mileage, and I installed the complete rebuild kit. Probably correctly...

 

[threewood]

Bad gas?

 

[BeepBeepRR]

Check your fuel pump pushrod make sure its not worn down. A short/worn pushrod will give you issues with fuel pressure loss.

Check this thread.

Post in thread 'Fuel Pump Slowly Dies'

Nov 18, 2025

Yep... I'd check the fuel pump push rod length. Think it should be just shy of 3.25"

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