Logo
FULL SITE MENU

1978 85hp johnson with idle problems

D

dannyvan

Member
"Here it goes, out of the wate

"Here it goes, out of the water the motor runs fine at idle, put it in the lake it did fine at idle and top end. Took it back out the same day and it would not idle unless I tilted the motor up a good ways (top end still good) The next morning motor would not idle at all and would run rough when I had the warm up lever up and then cut off. Got a tow and well you can imagine how our camping trip went. I rebuilt the carbs and my inline filter is clean. The part about idling good and then poor is an ongoing thing. The control box cables are stiff and 30 yrs old, wondering if they are putting the throttle back in the right position or something else. Please help!"
 
"well,first,..if the cables r

"well,first,..if the cables r 30 yrs old,..repl them........
second,...do a thorough,eng tunup..
what is the compression?
how is the ign system,and spark intensity?
are the plugs in good shape?
are the ign coils cracked and arcing to the coil bracket...or coiling brackets..happens.."
 
"with just one,of the idle jet

"with just one,of the idle jets stopped up--number 6 in pic,will cause idle prob--
251524.png"" alt=""
 
"OK, I will start with the cab

"OK, I will start with the cables - In the mean time I checked the compression, 112 to 114psi on all, new plugs were already in, ignition coils look good, not sure how to check spark intensity?
do you reccomend cleaning the carbs again? Thanks for the diagram."
 
"it depends on how thorough ,u

"it depends on how thorough ,u were,to begin with,and if,u can narrow it down,to fuel,or ign problem,at idle...compression,sounds great.ur eng,may just be idling too slow,...try speeding it up a bit,before anything drastic."
 
"Every time I adjust the idle

"Every time I adjust the idle it runs fine. It might last for an hour or all day, then it won't idle at all. I guess I'm looking for somthing obvious and hoping nothing major. Fixing to order the control cables since their so old and debating on looking into the carbs. Any more suggestions?"
 
--get a de-carb solution...brp

--get a de-carb solution...brp's eng tuner
merc power tune
yamaha ring free
auto parts sea foam..
do it 2-3 times..
 
Back
Top