Engine bogges down on acceleration

[panasonic]

Yes it has a control box on it now. The tech said tank had a leak letting rain in. When I got it back, it ran great for an hour or so. We stopped to let the grandkids fish for an hour or two. Started right up and ran great again for 5 minutes and then it bogged down and died. It started back up but would only run at low rpm. I took it out of the water and rebuilt the carburetor. Put it back in the water and it was great for about an hour or so. Stopped to fish and then headed back. After we headed back, it started to bog down and die. Idle speed only back to the house.

What kind of control box do you have? And is there a alarm buzzer on it.

I am not sure about the one you have... but if you pull the safety lanyard off and crank the engine, the alarm should sound....if it is working.

Also do you have a tach? If so what kind?

Please answer all the questions so we can try and help you figure out what may be wrong

[Thelureman]

It has a Yamaha control box, and an alarm. The boat don't have a tact.

[panasonic]

Does the alarm work? Pull the safety lanyard off the control box and crank the engine over....the alarm should sound.

[Thelureman]

Yes it works.

[panasonic]

I don't have a problem starting it. Its just when I try to excellerate that it bogs down.

Next time it happens, the engine won't accelerate this is, have someone pump the primer bulb quickly, and see if this makes a difference.Have you tried this?

[Thelureman]

Hi, yes I have. Do you think it could be the fuel pump?

[panasonic]

Yes possibly...It seems strange that it runs good for around 30 minutes or so and then starts to run crappy AFTER it gets hot and sits a bit. To me that seems like a heat problem....some component failing when heat soaked.

Rebuilding the fuel pump is a easy process and pretty cheap as well, it would not be a waste of money to do it anyway... due to the age of your engine.



Do you have a spark tester? Can you check that all cylinder's are firing when this happens again. That is what I would do. You need to check things out when the problem is occurring.

[Thelureman]

If it was in the firing order, would it not start right up. After it Boggs down and dies, it will fire right back up. It just won't let me accelerate.

[panasonic]

If it was in the firing order, would it not start right up. After it Boggs down and dies, it will fire right back up. It just won't let me accelerate.

It will most likely fire up and idle on only one cylinder ,probably rough but I think it would run, but not well at all.

I would rebuild the fuel pump as already stated. Cheap and easy.

And check for spark on both cylinders when this happens again.... this will eliminate that part of the equation. Checking for spark is the easiest trouble shooting you can do.

Check all the wiring and connections for chafing and loose connections...again cheap and easy.

I am not there to see and hear the engine and it is very difficult sometimes to find these problems. We can only offer suggestions...its up to you if you want to take these suggestions and try to help yourself.

[Thelureman]

Ok, I'll try this and let you know. Thanks

[calif-victim]

Is the fuel tank ventilated?? if there is not enough air to replace fuel being used then the tank will develop a vacuum and fight the fuel being pulled to the motor.

[Thelureman]

Hi, yes it's vented and open. Found out that if I hold my hand over the carburetor intake, it will run like a banshee! Not getting enough fuel. How do I fix this?

[99yam40]

carbs need cleaning if the motor has carbs