Could be one of three things: 1. Check fuel pressure from fuel pump to carbs. 2. Dirty or partial clog in low speed jet 3. If its got good fuel pressure and the low speed jet does not have a clog.....you may want to try turning the low speed idle screw clockwise until it LIGHTLY seats. Then turn it out 1 1/2 turns counter clockwise. This will give you a good starting point for adjustments from there. If it continues to sneeze like its doing now....turn the low speed idle screw 1/4 turn counter clockwise and wait 15 seconds for the motor to take to the adjustment. If it continues to sneeze give it another 1/4 turn counter clockwise until it stops sneezing. If you get to a point where you hear the motor start to idle down during these adjustments turn the low speed idle screw clockwise 1/4 turn and leave it there. If there is no other problems with the motor it should idle and not cut off.
Sounds like you have a air leak in your fuel lines and it’s lean sneezing and running out of fuel , replace all your fuel lines or may even be your fuel pump
fuel line leak 100%. i have that exact same motor. was sneezing cuz of a pinhole leak. theres alot of pressure from the fuel pump which sucks air from any hole it has before the pump.
Make sure the throttle plate is totally closed at Idle or no matter what you do you wont get rid of that lean sneeze . Even though the suggestions here are helpful ,what I'm telling you is your problem. Evinrude tech 45 yr's
Not specific enough Mr.45. You didn't mention the mechanical issue. The problem here is the missing linkage bar between the white "lean/rich knob" and the throttle plate just north of the knob. It's a small stainless steel linkage post, like a tiny bike pedal arm. 4 or 5 inches long. Without this part, the air/gas mix can't be adjusted. Can probably order another from Evinrude or makeshift something out of stiff coathanger until you can do something else. I know because I had to fix mine. Pretty simple fix.
Sounds like it is dropping a cylinder, have you tried new plugs? These engines have a pretty funky idle due to eviromental recirculation designs...The engine has to get up to temperature also, or it won't idle worth a damn...
@@samsvintageoutboards6847 Yeah, I guess you are right, seems like the usual lean spit. Can't ever adjust these engines properly, they will lean spit when dialed in so you have to leave them slightly rich. This one doesn't seem to respond even to the extreme rich settings.
Lean sneeze. Carb rebuild, blow out jets. Start at 1.5 turns out and keep adjusting the air/fuel like you are in the video til it idles high. Should be good
lightly seat it back back out 1 1/2 turn crank it out it in gear and keep backing it out till it idles then Reve it up 3 or4 times and it should idle buy it's self now you fuel and timing is set for a certain rpm you done
If you look at your lean - rich adjustment knob (center knob by choke) it's turning by itself when engine is running. That needs to stay put where you adjust it.
The problem here is the missing linkage bar between the white "lean/rich knob" and the throttle plate behind the white plastic rotator just north of the knob. You can see the holes that would hold the linkage bar in both white "free spinning" plastic pieces. The plastic ages, and those holes crack or bore out and you lose the bar through vibrations. If you're lucky, it might be sitting somewhere in the engine housing. These white plastic pieces shouldn't turn freely. It's like a hot/cold water sink or bath faucet knob. The bar is a small stainless steel linkage post, like a tiny bike pedal arm. 4 or 5 inches long. Without this part, the air/gas mix can't be adjusted. Can probably order another from Evinrude/Johnson or makeshift something out of stiff coathanger until you can do something else. I know because I had to fix mine. Pretty simple fix.
That is not his issue, the linkage is merely a convenience piece so you can make minor fuel ratio adjustments on the fly without removing the cover. He is adjusting the fuel screw in the video manually and it is not moving freely on its own.
Could be one of three things:
1. Check fuel pressure from fuel pump to carbs.
2. Dirty or partial clog in low speed jet
3. If its got good fuel pressure and the low speed jet does not have a clog.....you may want to try turning the low speed idle screw clockwise until it LIGHTLY seats. Then turn it out 1 1/2 turns counter clockwise. This will give you a good starting point for adjustments from there. If it continues to sneeze like its doing now....turn the low speed idle screw 1/4 turn counter clockwise and wait 15 seconds for the motor to take to the adjustment. If it continues to sneeze give it another 1/4 turn counter clockwise until it stops sneezing. If you get to a point where you hear the motor start to idle down during these adjustments turn the low speed idle screw clockwise 1/4 turn and leave it there. If there is no other problems with the motor it should idle and not cut off.
Wesley Warren hmm
Thanks for posting the video and thanks for the comment. This helped me sort my 74 Evinrude rough idle problem. 👍
Sounds like you have a air leak in your fuel lines and it’s lean sneezing and running out of fuel , replace all your fuel lines or may even be your fuel pump
dá medo esses motores é muito caro as peças
fuel line leak 100%. i have that exact same motor. was sneezing cuz of a pinhole leak. theres alot of pressure from the fuel pump which sucks air from any hole it has before the pump.
Make sure the throttle plate is totally closed at Idle or no matter what you do you wont get rid of that lean sneeze . Even though the suggestions here are helpful ,what I'm telling you is your problem. Evinrude tech 45 yr's
What is the throttle plate? I can't get mine to start unless I have the throttle wide open. If I let off the throttle it dies.
Not specific enough Mr.45. You didn't mention the mechanical issue. The problem here is the missing linkage bar between the white "lean/rich knob" and the throttle plate just north of the knob. It's a small stainless steel linkage post, like a tiny bike pedal arm. 4 or 5 inches long. Without this part, the air/gas mix can't be adjusted. Can probably order another from Evinrude or makeshift something out of stiff coathanger until you can do something else. I know because I had to fix mine. Pretty simple fix.
Sounds like it is dropping a cylinder, have you tried new plugs? These engines have a pretty funky idle due to eviromental recirculation designs...The engine has to get up to temperature also, or it won't idle worth a damn...
Sounds more like a lean miss to me like he isn’t getting enough fuel
@@samsvintageoutboards6847 Yeah, I guess you are right, seems like the usual lean spit. Can't ever adjust these engines properly, they will lean spit when dialed in so you have to leave them slightly rich. This one doesn't seem to respond even to the extreme rich settings.
@@fleetwin1 lol yea i had mine at like 10 turns out and it still ran. ran like shit but still ran.
Have you tried venting your gas tank had that problem with mine
Lean sneeze. Carb rebuild, blow out jets. Start at 1.5 turns out and keep adjusting the air/fuel like you are in the video til it idles high. Should be good
these 1972 evinrudes dont run at 1.5 turns. it immediately sneezes at that. its more like 3 or 4 turns out.
I have same engine same problem. Did you diagnose it yet by chance?
See my comment
Sounds like the carb bowl is full of water.
lightly seat it back back out 1 1/2 turn crank it out it in gear and keep backing it out till it idles then Reve it up 3 or4 times and it should idle buy it's self now you fuel and timing is set for a certain rpm you done
Is the rich lean unhooked or is adjusting as the motor runs. Could be a issue. Jw if you got it figured out.
If you look at your lean - rich adjustment knob (center knob by choke) it's turning by itself when engine is running. That needs to stay put where you adjust it.
K H the rod isint hooked up.... The low jet is not moving in the carburetor...
@@niceguynnc1 well there’s ur problem🤦🏼♂️ u need to have that hooked up, some people should just stay away from old outboards and buy a brand new one
Este es un motor fuera borda 40 ebinrude
I have a 1972 does the same thing you figure out the reason?
Had the same problem my fuel line was too long and problems solved itself
So you got a shorter fuel line and it's ok now ?
@@SoleAdventuresNZ yes the fuel pump was working to hard I needed my to be long to be my weight up front
How far is your tank
You might need a new crank shaft seal they are common for those motors becuSe of the age.
@@outboardidiots3622 it's close but the line might be around 1 and a half meters long
The problem here is the missing linkage bar between the white "lean/rich knob" and the throttle plate behind the white plastic rotator just north of the knob. You can see the holes that would hold the linkage bar in both white "free spinning" plastic pieces. The plastic ages, and those holes crack or bore out and you lose the bar through vibrations. If you're lucky, it might be sitting somewhere in the engine housing. These white plastic pieces shouldn't turn freely. It's like a hot/cold water sink or bath faucet knob. The bar is a small stainless steel linkage post, like a tiny bike pedal arm. 4 or 5 inches long. Without this part, the air/gas mix can't be adjusted. Can probably order another from Evinrude/Johnson or makeshift something out of stiff coathanger until you can do something else. I know because I had to fix mine. Pretty simple fix.
I'm missing the same part on mine. Do you know what it's called so I can order one?
That is not his issue, the linkage is merely a convenience piece so you can make minor fuel ratio adjustments on the fly without removing the cover. He is adjusting the fuel screw in the video manually and it is not moving freely on its own.
@@Rootin-Tootin-Shootin whatever you say 👍
Clean the carby and change fuel pump diaphragm & fresh fuel, booooom buddy
Em yeah. And the fix?
Ultimately I gave up and bought a new boat 😂