Hi,
I have a 91 Mariner 150 hp outboard that has developed a high idle. Ser# ODO32093. The last time on the water it was running fine but at the end of the day when I slowed to an idle when entering the marina. it wouldn't idle down. It was around 1500 rpm which made it hard to shift to neutral. The next day the idle increase to around 2000 rpm. It ran fine once you accelerated and ran well at high speeds. I was advised to check the shift and throttle cables which I did and can find no kinks. The idle adjsment screw is tight and at idle sits against the stop. I disconnected the throttle cable and started the started the motor which immediately revved to over 2000 rpm. I checked all hoses for breaks on holes, including to the thermal valve and enricher. Everything is good. The carb butterflies are closed and stay closed through the entire throttle range. The trigger linkage is connected and moves freely. Can anyone help point me to what I should be checking next? Would a ad thrermal valve or enricher cause my high idle? Is there an easy way to test if they are good?
Thanks for any advice you can give.
I have a 91 Mariner 150 hp outboard that has developed a high idle. Ser# ODO32093. The last time on the water it was running fine but at the end of the day when I slowed to an idle when entering the marina. it wouldn't idle down. It was around 1500 rpm which made it hard to shift to neutral. The next day the idle increase to around 2000 rpm. It ran fine once you accelerated and ran well at high speeds. I was advised to check the shift and throttle cables which I did and can find no kinks. The idle adjsment screw is tight and at idle sits against the stop. I disconnected the throttle cable and started the started the motor which immediately revved to over 2000 rpm. I checked all hoses for breaks on holes, including to the thermal valve and enricher. Everything is good. The carb butterflies are closed and stay closed through the entire throttle range. The trigger linkage is connected and moves freely. Can anyone help point me to what I should be checking next? Would a ad thrermal valve or enricher cause my high idle? Is there an easy way to test if they are good?
Thanks for any advice you can give.
