My Setup:
1980, 350 sb
-I have a rubber hose coming out of the pre-existing metal fuel line running to a Holley electric fuel pump. The pump is mounted to the frame rail adjacent to where the mechanical fuel pump would be, it is vertical and pumping upward. The pump feeds a regulator that is mounted to the front top of the block. A plastic filter is between the regulator and the carburetor.
Pics: https://imgur.com/a/GQruKb3

Symptoms:
-If the car idles too long without moving, pressure is lost on the discharge side of the pump (indicated by the pressure gauge on the regulator) and the pump attempts to prime itself (evident by a loud clicking noise).
-The hose between the regulator and the pump is charred on the engine block side, I covered it with HVAC tape to see if it would help reject radiant heat.

Proposed new setup:
I'm going to mount the pump to the rear cross-member directly above the spare tire, can I just run rubber fuel lines down the fuel tank to connect it? Or is it better to bend the metal fuel feed line down? In the engine bay I want to mount the regulator where the blower motor relay is, bend the existing metal fuel line upward toward it and join the two with rubber hose. The regulator will discharge to the filter and an insulated fuel hose will run to the carburetor from the fire wall. Electrically, I plan on putting a regulator in the battery bay and running a wire from the IGN terminal at the fuse box(currently powering the pump), then another through the rear over the wheel well.

I don't want to get into it and have it be a waste, does this plan look sound? Also, are these pumps known to lose pressure like this? I imagine a safety feature to prevent over-pressurization on the discharge or recognize lack of fuel flow could cause it to disengage, but that's a stretch. The symptoms seem to pointing toward vapor lock on the suction end of the pump, since at idle the fuel is mostly sitting close to the block and there's a slightly upward bow in the hose before it dips down to the pump's suction. The fuel tank is gross and could have fouled the pump, but there are no issues when the car is moving or before the engine is sitting at temp. I have fiddled with the regulator, but it doesn't seem to do much.

The engine has been overheating. I'm flushing the cooling system once this is dealt with, but it could be contributing.

 

Why not go back to a stock mechanical pump?
Returning to the stock fan clutch set up would also be a good idea.

 

I'm running a electric pump as well. But to feed fuel injection. Also wondering why all of this when the stock mechanical pump works so well without all this complicated stuff.
unless you have a newer block without a fuel pump mount.
electric fuel pumps are pushers not pullers. Having it near the front of the car is a mistake.
Getting a 82 sending unit assembly with the intank pump and just changing out the pump for a newer one would be by far the best and easiest. Run the fuel lines over the top into the right quarter panel as per stock and well away from the exhaust.

 

You need to put the pump near the tank.......

Jebby

 

I have just finished installing a Holley Sniper Stealth EFI system on my 1968 C3 427 Convertible. To get the fuel system to work properly I was ready to buy a new tank with the pump assembly built into it. The salesman asked if my tank was in good shape or not. He then told me that Holley makes a Fuel Tank Module that replaces the original fuel tank level sender for my Corvette. It came with a new WalBro Pump and an in-tank regulator set to 58 psi so I have only one hose carrying fuel going to my EFI system.

With my Sniper system it primes the engine just like new cars do and you don't hear any pump sounds at all. On my 1968 Corvette the fuel sender is located on the bottom of the fuel tank which made installation easier yet. I drained the fuel out and installed the new module with the new sending unit and Pump/regulator all out of site inside the fuel tank. It took 20 minutes to do the actual swap-out and I have a perfect fuel system for going with the EFI system. One of the best parts is that the pump pickup screen was the new Holley Hydra-Mat which is nothing short of incredible the way it sucks up the fuel. The module with Pump, sending unit and regulator was less than $350 including a piece of Hydra-mat which makes it a deal in my book.
IF you are thinking of going EFI be sure to check out EFISystemPro.com and ask them what they can do for you. They really helped me out and offer outstanding service for years down the road!

 

I'm very new at this, my other car had no problems with just slapping in an electric pump, but the engine bay was much larger. This sat in a field since 03 before I bought it, everything rubber cracked or eroded. I was fixated on putting something in that would last longer than a rebuilt mechanical pump and was easier to control fuel flow, in hindsight the mechanical pump would've been better. If I wasn't on a shoestring I'd jump at EFI. The 82 sending unit sounds like a great option, thank you.

Is a direct connection fan a problem? It wasn't my addition, but I guess GM wouldn't put extra material into a clutch if they didn't have to.

 

Why would you install a rebuilt mechanical in an 81? A new one is the way to go.
Factory type fan clutch is thermostatic, less noise and drag ,adjusts speed for temperature changes.

 

An electric pump needs to be mounted near the tank, and below fuel tank level so the pump does not have to "suck" on the inlet fuel. Additionally, you need to be running a return fuel line from your engine compartment area near the carb so the electric pump is never dead-headed. The return line will solve your problem along with correct mounting/location of the pump.

Lars

 

And the line near the block that gets heat damaged. Relocate it. When idling, you lose airflow thru engine compartment from the car moving thru the air. The fan only does so much and that is focused on the radiator.