| Author |
Message |
    
chris roper
New member
Username: croper
Post Number: 1
Registered: 07-2009
| | Posted on Tuesday, July 28, 2009 - 10:28 pm: | 
|
i have a mid 90's yamaha 9.9 4 stroke that has been giving me some trouble. It starts beautifully and will rev perfectly but in about 20 seconds it idles a bit rougfh and if you try to give it some throttle it craps out and almost stalls. If ytou turn it down it will idle but a bit rough. I have changed plugs, removed and cleaned out t5he carb jets, and used most of a can of combustuion chamber cleaner and I still have the same problem. The odd thing is that every time I start it it runs great for that 20 msec and then it does the same thing. Maybe a fuel pump? |
Daniel Seliger
New member
Username: dansel
Post Number: 1
Registered: 10-2009
| | Posted on Saturday, October 10, 2009 - 06:21 pm: |
|
I have the same problem. I appear to have overcome it dying completely by adjusting the idle screw to a satisfying position, but the engine still wanders at idle and even when in gear at low RPMs. Have you found a solution yet? |
brian guse
Member
Username: mtcooler
Post Number: 5
Registered: 07-2009
| | Posted on Sunday, October 11, 2009 - 12:00 am: |
|
had the same problem with my 94 9.9 4 stroke found the problem to be the intake gasket had a small crack in it. |
jamie campbell
Advanced Member
Username: outboard_doctor
Post Number: 652
Registered: 02-2009
| | Posted on Monday, October 12, 2009 - 03:46 am: |
|
ou have a fuel pump problem once you prime up the carbys it will run great untill the fuel level in the bowl drops. Replace the fuel pump |
