Electric fuel pump on a 76 merc 1500

[KG4]

I want to put an electric fuel pump on my 1500 L6 merc.How much fuel pressure do they take?Thanks Bob.

[MARINER RACING]

I think those carbs call for 3psi
not certain though
if no one comes up with a defenite answer
gimme a hollar at the shop and ill look it up for you
good luck....Jay @ SST Marine 561-687-3636

[TAXXIVADER]

kg4 . the tower of power stock fuel pump only had an output of 3-4 psi . so yes ya could replace this wit an after market leccy pump , just make sure it dont exxeed the pressure mentioned or you will just get a flooded carbys also good time to check your float levels whilst your at it......

[capnzee]

Literally, just about any 12v electric automotive fuel pump that will hold 3 to 5 lbs of pressure will work. One of the favorites is the Carter. Capnzee

[crazy horse]

I've been feeding my 76 XS with a red Holley and reg. for over 20 years. The reg. is set at 4 lbs. I've never had any problems with flooding at that pressure. ;)

[KG4]

Thanks guys.

[Jeff_G]

I use a Walbro, but the red Holly as posted is fine. When you set the regulator it can take as much as 5 or 6 lbs. usually. I set mine between 4 and 5 but after I do I test it for flooding.
Remove the engine cowl, back the boat into the water but don't take it off the trailer, just enough to totally cover the lower unit. After warming up the motor, shift into gear and slowly take it up to WOT. Watch for flooding particularly near WOT. If no flooding then you are good to go.

[capnzee]

Question: why would flooding occur when you rev the engine and not when you are at idle? The pump shouldn't know the difference and you are relieving pressure in the carburetor by sucking more fuel out of the fuel bowl by high revs. I learn something new every day so why not today? Capnzee ;)

[Jeff_G]

Actually it isn't really a flooding but a overfill from the float bowl cover vent. The motor is using so much fuel, and it is very aeriated going into the bowl that it overcomes the needle and seat, float tension and bubbles out all over the place. At lower Rpm's it is more regulated by the fuel flow through the carbs. This applies to inlines particularly. Different motors will act differently as will the carb settings and manufacturer of the needle and seats.

[capnzee]

Never thought of it that way, :rolleyes: thanks for the info! I've never had the problem with any of the pumps that I have used--but, I always buy 5 psi type automotive pumps. Capnzee :)