4.3 Fuel Problems (Electric Fuel Pump)

ichabod

Recruit
Joined
May 17, 2008
Messages
2
Hi everyone,
I have a 1996 Cobia with a 4.3 in it. Last year I replaced the starter but never had a chance to take it out and fire it up, I just made sure it cranked. When I pulled it out this year it won't run (so it's been sitting for about 2 years). I thought maybe I wired the starter wrong but I checked it and it looks ok.
When I crank it, I'm not getting any fuel in the carb. At first I wasn't hearing the fuel pump run, so I took off the connector to it and made sure it was getting power. It gets ~10.3 volts while cranking and then ~12.3 volts after cranking for a few seconds (I'm assuming while there's still some oil pressure). I put the connector back on and now at least I can hear the pump hum when I'm done cranking it....but still no fuel.
I pull the outlet steel tube off of the pump and put a rag in it to catch any gas and turned it over yet again, no gas comes out but the pump hums. Could the pump "hum" but still be defective?
The only other thing I've done is put a new fuel/water filter on it, and that is also still dry. I read on another post to fill it up and see if that helps things, I'll try that in the AM, but does anyone have any other suggestions? If I put fuel in the separator and it doesn't come out of the pump could there be any other reason for it not to do so other than a bad fuel pump?
Also, are there any tricks to getting the fuel lines off? I've only had the boat a few years and the nut on the fuel line at the carb is stuck and slightly rounded. Who knows when the carb fuel filter was changed. I put some WD-40 on it and tapped it with a hammer to try to loosen it up a bit but it doesn't seem to be helping.

Thanks guys for any help!

-Ich
 

capecodder116

Petty Officer 2nd Class
Joined
Jan 15, 2007
Messages
108
Re: 4.3 Fuel Problems (Electric Fuel Pump)

I'm assuming you have fuel in the tank. Have you checked pick up line in the tank, fuel lines leading to the fuel pump, screen, anti-sihpon valve,? Try taking a fresh 5 gallon jug of fuel, disconect the line at the fuel pump coming in from the tank and install line from remote fuel jug to the fuel pump and see what happens.
 

brunolund

Chief Petty Officer
Joined
Jan 26, 2008
Messages
439
Re: 4.3 Fuel Problems (Electric Fuel Pump)

filling the fuel filter should help. your fuel pump needs to be primed because they cannot pump air very well, if at all.once you get fuel in the line, it should work fine.
 

ichabod

Recruit
Joined
May 17, 2008
Messages
2
Re: 4.3 Fuel Problems (Electric Fuel Pump)

Thanks! I filled the separator and put some gas in the fuel pump, put a little in the carb, and she fired right up! Thanks guys!
 
Top