This seems like a good subject to start with, maybe it will solve a few problems, hope so. On the forums I have seen that some wonder why electric fuel pumps are not on the older rngines. I also see a few saying it is not safe -- but they obviously have not tried to do the conversion. I have done two so far with good success on both, one on a triumph Spitfire 1500, the other on a 1987 Evinrude 50 twin. The car to check a basic install where leaks are not as dangerous, blocked off the old pump.
Ok, here goes! Why would I want to convert to 12V. First you can get rid of that squeeze bulb primer, forever!! Next is changing tanks easier without stopping the motor, if you have a crossover valve set up. You can regulate the fuel flow for trolling to full speed operation more precisely. More power is available at top end, at a slight cost in fuel, if you will control the fuel pressure a bit more. No more dead diaphragms, or rebuilding the pump due to poor fuel. Safety is having two pumps in the system like the new outboards often have. You can transfer fuel from a main tank to a portable with a switch, no hand pumping. Clean out old fuel in the hose by removing the end barb, and pumping through new fuel.
First, is replacing all fuel lines, for safety. Get the best factory line for inside the motor cowling, a new one, and redo all the hose clamps, as you will have more pressure so you need fool proof lines.
I bought transparent, kevlar reinforced fuel lines for the outside tank to cowling plug-ins from a local dealer in automotive and commercial hoses. You can see the fuel when moving, air pockets if its not, and check fuel flow through the lines by eye.
The pump is a "Mr Gasket #42S for smaller car engines, so you have to add a regulator to reduce the pressure down to about what the Evinrude book says, most motors will vary by carb settings. I found that a max. pressure is 4 to 5psi running at cruise, and reduced to 1.5 to 2.0psi around idle speeds works for mine. I used an EMPI variable pressure regulator, after the pump, and before the fuel filter. The water/fuel filter in the lines - after the pump,- smooths out the fuel flow a bit, I believe. The pump puts out a full 42 lbs, and will not work without a variable flow regulator !! My car was very sensitive, had to be adjusted for exact pressure to the Stromberg carbs, the Evinrude was a lot easier, I went by a touch over the Clymer outboard repair book pressure. Yes, too much pressure will flood the carbs, but the fuel filter, and old "but good" original pump in the line will help even out the flow. That can be adjusted out on dock trials.
So, installing an electric pump is not hard if you read the notes. The pump is installed at a 45 degree angle, at the level of the lowest tank base, a shut off valve can be installed here to stop fuel from siphoning during storage. I put the pump 45deg. base on the deck where I can see it at all times, Just in case. The pump makes a small humm when running, so I can remember to shut it off. On the car, with more cubic inches, I removed the stock fuel pump, in the boat I rebuilt the stock diaphragm fuel pump so both would work. There is a new fuel diaphragm material thet is more ethanol resistant than before, on a Sierra 18-7352 pump anyhow. The diaphragm is Sierra #18-7800, but I haven't gotten that one in yet, and I hope it will be the right material. One I got was A GLM, that one had the old non-reinforced material, so not all are the new stuff yet.
The factory says they are working to redo the old rubber ones, but many dealers, or on line, may have old stock non-ethanol diaphragms on their shelves to sell first. The new material is a "satiny" looking stuff with probably a woven core, as it seems a bit thicker, maybe glossier is another word. I used both pumps so I will have both on line and working, just in case. Do not forget the screw clamps on every connection.
I can hear the pump running, but I also chose to wire it to a dash switch, fused, with a red ON light. I can pump fuel to other containers at will, or to clean old fuel out of the lines. Having control of the fuel makes it easier to clear overchoking, but we don't ever do that ?? Some want the gas to stop if the motor does, so it can be wired through the ignition switch, thats ok too -- my car does that. On the boat, I want a bit more control of fuel pressure, cruising at different loads or speeds, when and which, tank it comes from. I installed an on-off rocker switch, with a bright light by the wheel, so I know the pumps status at any time, and I check the pressure, which mostly is set at 3psi on the regulators rotary dial, and varied a bit to fit what I'm doing, trolling, sunset harbour cruise, or max river speeds.
I hope this helps some of us who want better fuel delivery, without the antique vacuum flapper type gas pump. I also got a slight increase in speed when I switch to the electric pump, now that I have had time to work with it. I can't predict what your results might be with your equipment and it's condition, so go slowly, check everything twice, be sure you have no fuel leaks, check your plug indications for too lean or overly rich mixtures. This is my second season with my setup, wouldn't go back for sure.
There will be comments, so Thanks to all, Cal
Ok, here goes! Why would I want to convert to 12V. First you can get rid of that squeeze bulb primer, forever!! Next is changing tanks easier without stopping the motor, if you have a crossover valve set up. You can regulate the fuel flow for trolling to full speed operation more precisely. More power is available at top end, at a slight cost in fuel, if you will control the fuel pressure a bit more. No more dead diaphragms, or rebuilding the pump due to poor fuel. Safety is having two pumps in the system like the new outboards often have. You can transfer fuel from a main tank to a portable with a switch, no hand pumping. Clean out old fuel in the hose by removing the end barb, and pumping through new fuel.
First, is replacing all fuel lines, for safety. Get the best factory line for inside the motor cowling, a new one, and redo all the hose clamps, as you will have more pressure so you need fool proof lines.
I bought transparent, kevlar reinforced fuel lines for the outside tank to cowling plug-ins from a local dealer in automotive and commercial hoses. You can see the fuel when moving, air pockets if its not, and check fuel flow through the lines by eye.
The pump is a "Mr Gasket #42S for smaller car engines, so you have to add a regulator to reduce the pressure down to about what the Evinrude book says, most motors will vary by carb settings. I found that a max. pressure is 4 to 5psi running at cruise, and reduced to 1.5 to 2.0psi around idle speeds works for mine. I used an EMPI variable pressure regulator, after the pump, and before the fuel filter. The water/fuel filter in the lines - after the pump,- smooths out the fuel flow a bit, I believe. The pump puts out a full 42 lbs, and will not work without a variable flow regulator !! My car was very sensitive, had to be adjusted for exact pressure to the Stromberg carbs, the Evinrude was a lot easier, I went by a touch over the Clymer outboard repair book pressure. Yes, too much pressure will flood the carbs, but the fuel filter, and old "but good" original pump in the line will help even out the flow. That can be adjusted out on dock trials.
So, installing an electric pump is not hard if you read the notes. The pump is installed at a 45 degree angle, at the level of the lowest tank base, a shut off valve can be installed here to stop fuel from siphoning during storage. I put the pump 45deg. base on the deck where I can see it at all times, Just in case. The pump makes a small humm when running, so I can remember to shut it off. On the car, with more cubic inches, I removed the stock fuel pump, in the boat I rebuilt the stock diaphragm fuel pump so both would work. There is a new fuel diaphragm material thet is more ethanol resistant than before, on a Sierra 18-7352 pump anyhow. The diaphragm is Sierra #18-7800, but I haven't gotten that one in yet, and I hope it will be the right material. One I got was A GLM, that one had the old non-reinforced material, so not all are the new stuff yet.
The factory says they are working to redo the old rubber ones, but many dealers, or on line, may have old stock non-ethanol diaphragms on their shelves to sell first. The new material is a "satiny" looking stuff with probably a woven core, as it seems a bit thicker, maybe glossier is another word. I used both pumps so I will have both on line and working, just in case. Do not forget the screw clamps on every connection.
I can hear the pump running, but I also chose to wire it to a dash switch, fused, with a red ON light. I can pump fuel to other containers at will, or to clean old fuel out of the lines. Having control of the fuel makes it easier to clear overchoking, but we don't ever do that ?? Some want the gas to stop if the motor does, so it can be wired through the ignition switch, thats ok too -- my car does that. On the boat, I want a bit more control of fuel pressure, cruising at different loads or speeds, when and which, tank it comes from. I installed an on-off rocker switch, with a bright light by the wheel, so I know the pumps status at any time, and I check the pressure, which mostly is set at 3psi on the regulators rotary dial, and varied a bit to fit what I'm doing, trolling, sunset harbour cruise, or max river speeds.
I hope this helps some of us who want better fuel delivery, without the antique vacuum flapper type gas pump. I also got a slight increase in speed when I switch to the electric pump, now that I have had time to work with it. I can't predict what your results might be with your equipment and it's condition, so go slowly, check everything twice, be sure you have no fuel leaks, check your plug indications for too lean or overly rich mixtures. This is my second season with my setup, wouldn't go back for sure.
There will be comments, so Thanks to all, Cal
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