Boat runs great for under a minute, and dies....( I'm lost )
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Originally Posted by RogerBacon
Could it be a vent issue on the tanks. If air can not get in, fuel can not get out.
This is my vote...the vents allowing air back into the tank are plugged. Try leaving the gas cap off and see if the problem is resolved.
Could it be a vent issue on the tanks. If air can not get in, fuel can not get out.
This is my vote...the vents allowing air back into the tank are plugged. Try leaving the gas cap off and see if the problem is resolved.
Fiddled with the fuel pump today.
Removed the regulator I put in ( just in case ) and went from 30 gph to 40 gph via stop watch and gallon jug.
I'm going to remove the electric fuel pump that I put by the selector valve and see how much I gain.
I still don't understand why it died at idle.
Removed the regulator I put in ( just in case ) and went from 30 gph to 40 gph via stop watch and gallon jug.
I'm going to remove the electric fuel pump that I put by the selector valve and see how much I gain.
I still don't understand why it died at idle.
is it backfiring at all? carbon buildup causing predet? octane too low? are you using marina fuel or highway fuel?
I've seen 12V ignition wires do this if there is an internal break, such as the wire leaving the dizzy to the coil, or leaving the electronic module in the bottom of the dizzy.
I've seen 12V ignition wires do this if there is an internal break, such as the wire leaving the dizzy to the coil, or leaving the electronic module in the bottom of the dizzy.
Like others have stated, it acts like it is running out of gas. Your mentioning that it surges before it dies is a dead giveaway. Also, just because the fuel pump is new doesn't mean that it isn't defective. Can you hear it running after the engine dies? After it dies, have you ever removed the spark arrestor and looked down into the carb throat while operating the throttle to see if the carb has any gas in it? It still could be an electrical issue (power supply to the fuel pump), just not an ignition issue IMO.
I think I figured out a big issue.
I removed the electric primer pump that I had at the selector valve. Went from 40 gph to 50.
So yesterday, we were running the boat at 30 gph.
Removed the pressure regulator, went to 40 gph.
And removed the" back up " pump I've had on it for all these years, it now flows 50 gph.
I'm sure that is a huge difference in my situation
Now I need to wet test it....
I removed the electric primer pump that I had at the selector valve. Went from 40 gph to 50.
So yesterday, we were running the boat at 30 gph.
Removed the pressure regulator, went to 40 gph.
And removed the" back up " pump I've had on it for all these years, it now flows 50 gph.
I'm sure that is a huge difference in my situation
Now I need to wet test it....
You should be using a pump designed for carb applications that is inherently low pressure. Thus no need for a regulator.
One pump is all you need. If you are concerned about failure on the water you could fit some tees and valves to have a "hot spare" pump in parallel. Don't put them in series.
One pump is all you need. If you are concerned about failure on the water you could fit some tees and valves to have a "hot spare" pump in parallel. Don't put them in series.
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the float is probably not operating properly, when surging the engine is probably very lead and running on vapor. take the bowl off and clean out the float system, make sure its operating properly, try pumping the ball really well when its running to keep the fuel flowing as a check before it starts surging. been down this road before.
The boat probably had a mechanical fuel pump when it was made. Why go to an electric fuel pump? What method are you using to stop the fuel pump if the engine stalls? You need to have some method? Big safety issue.
I had some work done on my boat and they installed an electric fuel pump. But did a poor job of wiring it. The boat now has a mechanical fuel pump. I did not view any way of powering the electric pump and stopping it if the engine stalled to be very reliable from a electric perspective.
The carb probably has a small inline filter inline with the fuel inlet.
I still would suggest to try the boat with the fuel coming from a 5 gallon fuel container.
I had some work done on my boat and they installed an electric fuel pump. But did a poor job of wiring it. The boat now has a mechanical fuel pump. I did not view any way of powering the electric pump and stopping it if the engine stalled to be very reliable from a electric perspective.
The carb probably has a small inline filter inline with the fuel inlet.
I still would suggest to try the boat with the fuel coming from a 5 gallon fuel container.
One more spark problem to check for is a loose connection in the lead that goes up under the distributor to the points. The distributor plate moves and can cause the symptoms you describe. It`s happened to me and the lead is a fine wire that will handle movement. This problem acts similar to a bad condenser.
The mechanical fuel pump pivot rod worked it's way out. We decided to put this electric pump in because we can run the carb dry after an outing.
I bought a mechanical pump for it, it was special compared to the typical clockable small block Chevy pumps probably because it's Swedish. The m22010 pumps don't clock correctly on the bottom of the pump.
I'm probably going to put the mechanical pump on there.
The fact the electrical pump was limited to 30 gph with all the crap I had restricting it makes me want to do a test run with the electrical one.
I bought a cap, rotor and wires today. Going to change all that out before the next wet test.
This morning the pump filled a gallon of gas in 70 seconds
I bought a mechanical pump for it, it was special compared to the typical clockable small block Chevy pumps probably because it's Swedish. The m22010 pumps don't clock correctly on the bottom of the pump.
I'm probably going to put the mechanical pump on there.
The fact the electrical pump was limited to 30 gph with all the crap I had restricting it makes me want to do a test run with the electrical one.
I bought a cap, rotor and wires today. Going to change all that out before the next wet test.
This morning the pump filled a gallon of gas in 70 seconds
Is your electric pump wired through an oil pressure switch? If so, is the switch any good? Does your oil pressure go up as the RPMs climb?
Another thing to think about, does the electric pump have an idle mode like a mechanical pump? I guess since the boat starts right back up it probably is not flooding.
Maybe a real reach but in 1985 gas didn't have alcohol in it. I have a friend who recently built a 1969 irebird with a stroked Pontiac big block in it. He first put a 950 cfm Holley Quick Fuel on it and I was able to get it dialed in and run nice but it would cut out when it got hot. We tried all sorts of things and found it ran longer when we insulated the fuel line. I ended up solving the problem by putting a return line on it. Car ran great but then it stunk up his garage when it was parked inside and his central air would suck it up and make his whole house smell like gas. We ended up installing a Fast fuel injection system and some ungodly expensive fuel system vent. But anyway it seems like his fuel was boiling in the line.
Another thing to think about, does the electric pump have an idle mode like a mechanical pump? I guess since the boat starts right back up it probably is not flooding.
Maybe a real reach but in 1985 gas didn't have alcohol in it. I have a friend who recently built a 1969 irebird with a stroked Pontiac big block in it. He first put a 950 cfm Holley Quick Fuel on it and I was able to get it dialed in and run nice but it would cut out when it got hot. We tried all sorts of things and found it ran longer when we insulated the fuel line. I ended up solving the problem by putting a return line on it. Car ran great but then it stunk up his garage when it was parked inside and his central air would suck it up and make his whole house smell like gas. We ended up installing a Fast fuel injection system and some ungodly expensive fuel system vent. But anyway it seems like his fuel was boiling in the line.
Lower your fuel pressure. You need a regulator to not let pressure get over 7 psi if I remember correctly.
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The mechanical pump needs to be designed for marine use and have an outlet that goes to a clear tube that pushes gas into the carb if the fuel pump diaphragm breaks. At least the ones I am familiar with had that.
Jury rigging an electric fuel pump with any non marine sensor, switch or relay is not a great idea. Either they could spark or fail due to corrosion. The engine bay is a tough environment.
Jury rigging an electric fuel pump with any non marine sensor, switch or relay is not a great idea. Either they could spark or fail due to corrosion. The engine bay is a tough environment.
Donald, I've seen exactly the mechanical pumps you're talking about on speed boats. That was done so if the diaphragm was leaking, it would blow the excess gas into the carb and make it run badly so you would notice it and pay immediate attention to it. Without it, it would fill the engine's oil pan with gasoline.
Oddly, I never saw it on every day run of the mill marine engines which didn't get the constant attention of the big blocks found in Cigarettes and other go fasts.
The ONLY time I ever installed an electric pump on a boat was when we were building a new V6 for a friend's bowrider and used a block we bought at the junk yard. We already had it all machined and cleaned and after we installed the crank, rods and pistons, I noticed it wasn't machined for a fuel pump pushrod. Kinda late at that point so we installed a Stewart Warner marine fuel pump with a regulator and oil pressure switch. Worked great for about fifteen years.
Oddly, I never saw it on every day run of the mill marine engines which didn't get the constant attention of the big blocks found in Cigarettes and other go fasts.
The ONLY time I ever installed an electric pump on a boat was when we were building a new V6 for a friend's bowrider and used a block we bought at the junk yard. We already had it all machined and cleaned and after we installed the crank, rods and pistons, I noticed it wasn't machined for a fuel pump pushrod. Kinda late at that point so we installed a Stewart Warner marine fuel pump with a regulator and oil pressure switch. Worked great for about fifteen years.
Originally Posted by NYEngineer
Donald, I've seen exactly the mechanical pumps you're talking about on speed boats. That was done so if the diaphragm was leaking, it would blow the excess gas into the carb and make it run badly so you would notice it and pay immediate attention to it. Without it, it would fill the engine's oil pan with gasoline.
Oddly, I never saw it on every day run of the mill marine engines which didn't get the constant attention of the big blocks found in Cigarettes and other go fasts.
The ONLY time I ever installed an electric pump on a boat was when we were building a new V6 for a friend's bowrider and used a block we bought at the junk yard. We already had it all machined and cleaned and after we installed the crank, rods and pistons, I noticed it wasn't machined for a fuel pump pushrod. Kinda late at that point so we installed a Stewart Warner marine fuel pump with a regulator and oil pressure switch. Worked great for about fifteen years.
My boat has the fuel pump with the extra line line to handle a diaphragm failure. My boat has a GM 350 in a 24' sport cruiser.
Donald, I've seen exactly the mechanical pumps you're talking about on speed boats. That was done so if the diaphragm was leaking, it would blow the excess gas into the carb and make it run badly so you would notice it and pay immediate attention to it. Without it, it would fill the engine's oil pan with gasoline.
Oddly, I never saw it on every day run of the mill marine engines which didn't get the constant attention of the big blocks found in Cigarettes and other go fasts.
The ONLY time I ever installed an electric pump on a boat was when we were building a new V6 for a friend's bowrider and used a block we bought at the junk yard. We already had it all machined and cleaned and after we installed the crank, rods and pistons, I noticed it wasn't machined for a fuel pump pushrod. Kinda late at that point so we installed a Stewart Warner marine fuel pump with a regulator and oil pressure switch. Worked great for about fifteen years.
My boat has the fuel pump with the extra line line to handle a diaphragm failure. My boat has a GM 350 in a 24' sport cruiser.
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