I've tried searching a variety of ways, but haven't found anything that fixes my problem.
The boat is a 1991 Eliminator with a 350 Mercruiser and Alpha One drive.
When I got the boat, it had been sitting for an extended period of time with fuel in the tanks. The fuel had turned into gunk, so I replaced all the fuel system components and pressure washed the inside of the tanks. I installed new lines, fabricated new pickups, installed a new tank selector valve, a new Edelbrock carburetor, and a mechanical fuel pump from Sierra.
After that, I had an ongoing issue with fuel pump failures. I finally gave up and took it to a local boat shop. They suggested that remaining varnish from the tanks was causing the fuel pump failures and installed filters between the tanks and the fuel pump.
I recently figured out that the fuel pumps I was getting from Sierra were faulty, hence the high rate of failure. They provided me with two of their new style pumps which they say don't have the same problems.
Even after all this, I am only getting 1-2psi reading on a pressure guage installed between the fuel pump and carburetor. This is at idle with the boat on the trailer getting water from the hose. I tried to put it in the water but I can't get more than 1500-2000 rpm before the engine starves and dies.
I feared that some obstruction was causing this so I tried a couple of things:
-I ran a line from a gas can directly to the fuel pump, bypassing the boat fuel supply. The mechanical fuel pump only output 1-2 psi.
-I tried both fuel pumps. No change.
-I pulled the push rod and check for bends or kinks. It's straight and smooth.
-I installed an automotive electric fuel pump and it produced 4-7 psi on my guage. I fed it from both the fuel can and the boat fuel tanks and got the same pressure, 4-7 psi.
My current theory is that there is some failure in the fuel pump actuating that is giving me reduced output. I'm not sure what may be causing it except for a camshaft problem. When the boat runs on the electric fuel pump, it runs fine. No indication of a camshaft failure.
Based on my success with the electric fuel pump, my idea is to convert to a marine electric fuel pump with appropriate switches and wiring (oil pressure, starter).
Any suggestions or solutions are greatly appreciated! My dad and I having been beating our head against this one for more than a couple of hours and are ready to be done with it!
The boat is a 1991 Eliminator with a 350 Mercruiser and Alpha One drive.
When I got the boat, it had been sitting for an extended period of time with fuel in the tanks. The fuel had turned into gunk, so I replaced all the fuel system components and pressure washed the inside of the tanks. I installed new lines, fabricated new pickups, installed a new tank selector valve, a new Edelbrock carburetor, and a mechanical fuel pump from Sierra.
After that, I had an ongoing issue with fuel pump failures. I finally gave up and took it to a local boat shop. They suggested that remaining varnish from the tanks was causing the fuel pump failures and installed filters between the tanks and the fuel pump.
I recently figured out that the fuel pumps I was getting from Sierra were faulty, hence the high rate of failure. They provided me with two of their new style pumps which they say don't have the same problems.
Even after all this, I am only getting 1-2psi reading on a pressure guage installed between the fuel pump and carburetor. This is at idle with the boat on the trailer getting water from the hose. I tried to put it in the water but I can't get more than 1500-2000 rpm before the engine starves and dies.
I feared that some obstruction was causing this so I tried a couple of things:
-I ran a line from a gas can directly to the fuel pump, bypassing the boat fuel supply. The mechanical fuel pump only output 1-2 psi.
-I tried both fuel pumps. No change.
-I pulled the push rod and check for bends or kinks. It's straight and smooth.
-I installed an automotive electric fuel pump and it produced 4-7 psi on my guage. I fed it from both the fuel can and the boat fuel tanks and got the same pressure, 4-7 psi.
My current theory is that there is some failure in the fuel pump actuating that is giving me reduced output. I'm not sure what may be causing it except for a camshaft problem. When the boat runs on the electric fuel pump, it runs fine. No indication of a camshaft failure.
Based on my success with the electric fuel pump, my idea is to convert to a marine electric fuel pump with appropriate switches and wiring (oil pressure, starter).
Any suggestions or solutions are greatly appreciated! My dad and I having been beating our head against this one for more than a couple of hours and are ready to be done with it!
