Dies at idle, runs fine at WOT.

[pensacola]

I have a Yamaha 60 HP outboard. When I am at slow speeds or idle it wants to die. I have to flip the emergency fuel enrichment switch to get it to run at slow or idle speeds. But once I get it running I can switch the enrichment switch back to normal and give it gas and it will run fine at WOT. Is this a fuel filter problem or a carburator problem?

 

[triumph190]

Re: Dies at idle, runs fine at WOT.

It could be both. Replace the fuel filter(s) and rebuild the carb(s) then see how it performs. Fuel filters and carb kits are pennies a day compared to a engine rebuild because of a lean fuel mixture...guessing that it's 2-stroke...

 

[pensacola]

Re: Dies at idle, runs fine at WOT.

yes I am sorry its a 2-stroke. I have a good feeling its in the low speed part of the carb. If it was the fuel filter wouldn't it have problems at WOT also. The only time it acts funny is in really low speed or idle. It almost acts like it is idling too low. I think I got some water in the gas tank and in went through the motor. I emptied the tank and have ran a full tank of fresh gas through it.

 

[triumph190]

Re: Dies at idle, runs fine at WOT.

If you have a fuel restriction, like a dirty fuel filter, the fuel pump at WOT can pump hard enough to force fuel past the restriction, where as at idle the pump isn't pumping as hard so fuel can't pass through.

 

[pensacola]

Re: Dies at idle, runs fine at WOT.

Aww thank you. That makes sense. I just got another fuel filter so I am gonna try that.

 

[pensacola]

Re: Dies at idle, runs fine at WOT.

Well I took out the fuel filter and it had all kinds of garbage in it. So I replaced it and it didn't seem to help. But when I turned the idle up a little it stayed running. I am gonna have my mechanic come look at it tomorrow.

 

[TommyA]

Re: Dies at idle, runs fine at WOT.

Is this something that just happened all of a sudden or did it occur over a long period? If it happened overnight it might be your stator has lost the low side. This will reduce the spark you have at a slow idle but will operate fine at higher throttle. It is a simple check and would eliminate a simple repair.

 

[Yamajoe]

Re: Dies at idle, runs fine at WOT.

check you retart timing and link and sinc

 

[pensacola]

Re: Dies at idle, runs fine at WOT.

Is this something that just happened all of a sudden or did it occur over a long period? If it happened overnight it might be your stator has lost the low side. This will reduce the spark you have at a slow idle but will operate fine at higher throttle. It is a simple check and would eliminate a simple repair.

No this is a all of a sudden thing. Ran fine then know this.
How do I check the stator?
Also retart timing and link and sinc?
Please explain a little more.
I bought one of the engine manuals off of here and all it does is tell me how things work but not how to fix it.

 

[TommyA]

Re: Dies at idle, runs fine at WOT.

Not being familiar with the Yamaha engines it would be best for someone who has more experiance than me with your particular engine. I found I was having the same problem with my Mercury outboard and the stator was what I found to be the problem.

 

[pensacola]

Re: Dies at idle, runs fine at WOT.

We took the carbs off and there was water sitting in the bottom of each one. So we are rebuilding all three and hopefully it will be all good.