To mr ghost

"ghost i have same idle proble

"ghost i have same idle problem.this time i disconnected the throttle linkage,and reved the motor up slightly, and it is still fluxuating.thanks,larry."

Carbed or EFI? Choke coil spr

Carbed or EFI? Choke coil spring connected properly?

"Larry

if you cant maintai

"Larry

if you cant maintain a steady idle then there could be many resons.

there could be a vacuum leak or the carb may be old and in need of rebiuld, weak fuel pump not supplying enoygh fuel, bad air/fuel mixture screw settings.

Give us more info on the motor,

year of boat/motor
point ignition or electronic
when it was last tuned up and by who

we need more info....."

"OK i just reread your origina

"OK i just reread your original post

Best to keep your questions with your original so we do not have to go back and forth to get info

1988 350 4bbl so this has the merc electronic ignition thunderbolt IV

Idle surging is typically a vacuum leak and the question is from where!

Also when was the boat tuned up, new cap rotor and plugs?

20 + years you may just need a carb rebiuld with fresh gaskets

If you know someone who can help trace a vacuum leak that would be good to start. A can of carb cleaner and spray small amounts around carb and see if the idle changes........

My best guess at this point."

"thank's,guy's.i will

"thank's,guy's.i will do more test's,and repost.i took the carb off,and found some loose screws that hold the 2-flange's together.seem's a little better.will replace pump next.thank's again."