I can start and run my Nissan 3.5, 2 stroke, at low rpm's but as soon as I increase to more than approx. 20% throttle it dies. I am assuming some sort of carb issue. The reason I say this is because I let the engine sit in my garage all summer and when I recently used it I discovered no fuel in the tank. I am assuming fuel dried up in the carb also and gunked up a passageway/jet/float valve or whatever. I was hoping that just running it would clean it out but after running 1/2 hour or so this did not work. Is there some sort of additive I can use to fix this problem or do I have to take the carb off and clean? Thanks.
Outboard engine dies
- Thread starter Pat T
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Pat:
I would suggest that you just try running some carb cleaner (spray) through the air intake first. This MAY take care of the problem. If it doesn't you may want to consider removing the carb and checking the jets.
We just had a similar issue with our Nissan/Tohatsu 18. We actually put a carb kit in it, but found a spider nest in one of the high speed jets.
Go figure!
I would suggest that you just try running some carb cleaner (spray) through the air intake first. This MAY take care of the problem. If it doesn't you may want to consider removing the carb and checking the jets.
We just had a similar issue with our Nissan/Tohatsu 18. We actually put a carb kit in it, but found a spider nest in one of the high speed jets.
Go figure!
I have the same engine myself. I would recommend putting a small amount of fresh gas with some liquid carb cleaner in the tank and running it. When running, goose the throttle so that gas is drawn thru the high speed passages as well as the low speed. I use 5-10x the amount of carb cleaner than is specified- so if it says to use 1 oz per quart, I use 1 oz per 5-6 oz of gas. I really just want a high concentration of cleaner to dissolve any deposits. You might add a small amount of additional 2-cycle oil to account for the volume of cleaner.
Another 'trick' is to back out the needle jets and spray into them with carb cleaner. Unlike Steve Dion, I have found that spraying into the air intake just cleans the air intake passages. What I usually need is to clean the internal fuel passages, hence I use the liquid carb cleaner in the fuel. For sticky throttle or choke plates, carb spray in the air intake works well.
If the action above doesn't work, the I have always had to dissemble the carb and use a spray cleaner to force thru all of the passages- or soak the parts overnight in the liquid cleaner.
The only other running problem that I have had is that the engine will start and run fine for 1-2 minutes and then die. It will then restart and die again. I have tracked that failure mode to a bad plug.
Another 'trick' is to back out the needle jets and spray into them with carb cleaner. Unlike Steve Dion, I have found that spraying into the air intake just cleans the air intake passages. What I usually need is to clean the internal fuel passages, hence I use the liquid carb cleaner in the fuel. For sticky throttle or choke plates, carb spray in the air intake works well.
If the action above doesn't work, the I have always had to dissemble the carb and use a spray cleaner to force thru all of the passages- or soak the parts overnight in the liquid cleaner.
The only other running problem that I have had is that the engine will start and run fine for 1-2 minutes and then die. It will then restart and die again. I have tracked that failure mode to a bad plug.
Second kloudie1's post .... as the hose/tube used with pre-ethanolated fuels isnt compatible with the 'new' fuels and is easily 'attacked' & falls apart .... also check the tank cap vent to be SURE that its not obstructed.
The best thing you can do when you are done using your outboard for the day is to pull the fuel line off of the engine and run the carburetor and fuel system out of gas. That way it doesn't sit there fouling everything up. The 2nd best thing you can do is always put Sea Foam in your fuel tank, which is a fuel cleaner and conditioner and it will help keep your carb clean. But, always run it out of fuel by pulling the fuel hose when done. This will eliminate most of your fuel troubles. So simple, yet no one does it.
I've battled some "bad gas" issues in my Tohatsu. I've debated disconnecting the fuel line as Barnacle Bill suggested but I've found that this still leaves a small amount of fuel in the bowl, even if I choke it to keep the motor running as the fuel supply runs out. I can drain this residual fuel from the carb but it's a pain. For the moment I've not unplugged the fuel line. I figure that it's better to leave the bowl full versus just leaving a small residual amount of fuel is better. In my mind it's similar to the keeping the gas tank full. Less headspace, less moisture to absorb and degrade the gas.
I may be completely off base with my thinking here, so take this with a grain of salt. I'm open to any opinions too!
I may be completely off base with my thinking here, so take this with a grain of salt. I'm open to any opinions too!
drain the carb
Try draining the carb. Most carbs have a screw on the bottom that make this an easy task. Then take all the external jets and needle adjustments ( be sure to count the number of turn that it takes to seat the screws so you can put them back correctly ) out and spray the passages with carb spray. This works about 40% of the time for me. If that doesn't work take the carb off and take it home. Take it apart and clean it with carb spray and compressed air ( as in 100psi, not air from a can ). If you are careful you will not need to replace any gaskets.
Good luck
Try draining the carb. Most carbs have a screw on the bottom that make this an easy task. Then take all the external jets and needle adjustments ( be sure to count the number of turn that it takes to seat the screws so you can put them back correctly ) out and spray the passages with carb spray. This works about 40% of the time for me. If that doesn't work take the carb off and take it home. Take it apart and clean it with carb spray and compressed air ( as in 100psi, not air from a can ). If you are careful you will not need to replace any gaskets.
Good luck
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Pull the bowl off the carb, most likely your mainjet is clogged. You can use a small piece of wire to clean it out, along with carb cleaner. The mainjet controls from around 1/4-full throttle.
Either that or it isn't getting enough fuel period, which would be the filter.
If it starts, it isn't the plug. Hope this helps.
Either that or it isn't getting enough fuel period, which would be the filter.
If it starts, it isn't the plug. Hope this helps.
Re: Outboard Engine
Thanks for all the suggestions guys. I will try to tackle this issue over the weekend.
Thanks for all the suggestions guys. I will try to tackle this issue over the weekend.
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