86 Blackmax 150 hp bad idling.

[Iceman66]

Hi
My Blackmax has started to shoot when idling , appr. every 4-5 second.
It also hesitate a bit during acceleration, and runs a bit uneven at cruising speed.
Runs fine at 3/4 to full throttle.

There is no idle mix screw at the carbs.

Carb clean next or?

Other things I should check?

 

[Iceman66]

Re: 86 Blackmax 150 hp bad idling.

Added some omega 992 fuel injector cleaner in my fuel tank, ran the engine at 2000 rpm in neutreal in 10 minutes,then 5 minutes
at almost WOT, the engine is now idling very smooth , and no hesitating when throttle.

Some additivies does really the job they says!