climbing19861234
Recruit
- Joined
- Jul 26, 2011
- Messages
- 2
Hello,
I have a 1971 Evinrude 100hp electric shift outboard on a boat that I bought about a year ago. I don't know the history of the motor or the boat. When I first got it, it would run for maybe 30 seconds, then shut off. I first replaced the stock fuel pump with an electric fuel pump. The problem was still there, so I rebuilt both carburetors and discovered they were very clogged, keeping the float valve almost shut. After replacing the carbs the motor started running great (on land with earmuffs). Yesterday, I took the boat out to the lake (with new gas) and it started (reluctantly) and I was able to drive at low and high speeds for 2-5 minutes or so. When I slowed then engine down, it died (it didn't seem to cough or miss or anything, it was almost as though someone just turned it off). I was able to get it to start again after a few minutes but it would die as soon as I shifted into forward. At this point, I drained the carb bowls and the gas coming out seemed especially clear for an oil-gas mix (or maybe I am imagining this).
After being towed back to shore, I took the boat home and hooked it up to the earmuffs again and was able to start the motor (again it was more reluctant to start than I am used to). Once running out of water at just above idle speed, the motor didn't seem to care if it was in gear or neutral, but after running just above idle for a few minutes, the motor slowly lost RPM then died (again it didn't seem to misfire our cough or anything, it just slowly lost RPM until it died). The motor seems to be running cool (I can touch the heads and they are just warm, not hot and I did put in a new water pump and impeller a few months ago so I don't think that it is overheating).
At this point I am not sure what to do. It seems natural to first attack the fuel system by draining the tank and replacing the fuel lines and checking the pump and filter. I will probably also pull the carbs off again and do a quick clean on them as well (though I have probably run the motor less than an hour after the full rebuild). I will also pull and clean the spark plugs (although they are nearly brand new as well). If this doesn't work I will be at a loss. Perhaps the issue is in the ignition system. Maybe the coil or distributor or amplifier is malfunctioning when hot? I don't really know anything about the electrical system on the motor so if this sounds like a reasonable place to look next please let me know and any advice would be appreciated. I should also mention that the amplifier looks almost brand new (based on the condition of the wiring and insulation) and I have tried running with two different, newer, fully charged batteries.
Also, any advice on how to test my repairs without getting halfway across the lake before it breaks down? I think that I should test it under loaded conditions as it seems to run better with no load.
Thank you very much for your help.
PS - I won't be able to do any work on the boat until this weekend, so I may not be able to approach any advice or answer any questions I get until then.
I have a 1971 Evinrude 100hp electric shift outboard on a boat that I bought about a year ago. I don't know the history of the motor or the boat. When I first got it, it would run for maybe 30 seconds, then shut off. I first replaced the stock fuel pump with an electric fuel pump. The problem was still there, so I rebuilt both carburetors and discovered they were very clogged, keeping the float valve almost shut. After replacing the carbs the motor started running great (on land with earmuffs). Yesterday, I took the boat out to the lake (with new gas) and it started (reluctantly) and I was able to drive at low and high speeds for 2-5 minutes or so. When I slowed then engine down, it died (it didn't seem to cough or miss or anything, it was almost as though someone just turned it off). I was able to get it to start again after a few minutes but it would die as soon as I shifted into forward. At this point, I drained the carb bowls and the gas coming out seemed especially clear for an oil-gas mix (or maybe I am imagining this).
After being towed back to shore, I took the boat home and hooked it up to the earmuffs again and was able to start the motor (again it was more reluctant to start than I am used to). Once running out of water at just above idle speed, the motor didn't seem to care if it was in gear or neutral, but after running just above idle for a few minutes, the motor slowly lost RPM then died (again it didn't seem to misfire our cough or anything, it just slowly lost RPM until it died). The motor seems to be running cool (I can touch the heads and they are just warm, not hot and I did put in a new water pump and impeller a few months ago so I don't think that it is overheating).
At this point I am not sure what to do. It seems natural to first attack the fuel system by draining the tank and replacing the fuel lines and checking the pump and filter. I will probably also pull the carbs off again and do a quick clean on them as well (though I have probably run the motor less than an hour after the full rebuild). I will also pull and clean the spark plugs (although they are nearly brand new as well). If this doesn't work I will be at a loss. Perhaps the issue is in the ignition system. Maybe the coil or distributor or amplifier is malfunctioning when hot? I don't really know anything about the electrical system on the motor so if this sounds like a reasonable place to look next please let me know and any advice would be appreciated. I should also mention that the amplifier looks almost brand new (based on the condition of the wiring and insulation) and I have tried running with two different, newer, fully charged batteries.
Also, any advice on how to test my repairs without getting halfway across the lake before it breaks down? I think that I should test it under loaded conditions as it seems to run better with no load.
Thank you very much for your help.
PS - I won't be able to do any work on the boat until this weekend, so I may not be able to approach any advice or answer any questions I get until then.