89 Merc 100 coughing at idle (video)

[sawblade723]

Please watch the video below, the motor starts smooth but at 1:00 minute into the video it starts to cough. Does anyone know what would cause this?

 

[CharlieB]

Re: 89 Merc 100 coughing at idle (video)

Lean idle mixture.

If this is a recent change then it is time to clean your carbs as the idle circuits have lost a little flow due to the accumulation of mineral/crud.

 

[jigmister]

Re: 89 Merc 100 coughing at idle (video)

mine smokes alot more than that. Dose your always smoke that little?
mine sneezes at a few times when cold at idle.

 

[sawblade723]

Re: 89 Merc 100 coughing at idle (video)

Lean idle mixture.

If this is a recent change then it is time to clean your carbs as the idle circuits have lost a little flow due to the accumulation of mineral/crud.

Carb rebuilding is next on the list.

 

[sawblade723]

Re: 89 Merc 100 coughing at idle (video)

mine smokes alot more than that. Dose your always smoke that little?
mine sneezes at a few times when cold at idle.

Actually it is smoking a little more than it appears, It just doesn't show up well in the video.