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Spitting out the idle air bleed jet

S

scottg

New member
while trying to track down wh

while trying to track down why my '86 120HP Johnson is running rich at idle i noticed that while idleing the motor with the airbox off it was spitting out of the idle air bleed jets - about one spit every 3-4 seconds out of each carbs air idle jet. what would cause this?
 
Bad O-rings around the mixtur

Bad O-rings around the mixture screw.
 
where do I find this o-ring?

where do I find this o-ring? i know there is no o-ring under the idle and intermediate air bleed orifices.
 
"Scott,

You may have a floo

"Scott,

You may have a flooding condition due to faulty needle valves or sticky floats.

You should also check the intake reeds. Some may be bent or broken.

"
 
" floats and/or needle valves

" floats and/or needle valves or seats has been suggested before but i question wether it is possible that all 4 carbs would have the same problem at the same time? Or is it possible that 1 carb can foul all 4 plugs?

As far as the intake reeds go, from what I've read
popping sounds out of the carb throts is an indication of a lean condition caused by bent or broken reeds unless i misunderstood something? "
 
"Scottg.... If by "airbox&

"Scottg.... If by "airbox", you're speaking of the heavy duty carburetor intake face plate assy, the engine will do all sorts of weird things if you attempt to run it without that assy attached. It acts as sort of a air restrictor, and that thick gasket that presses up against the carburetors absolutely must be there.

I realize, as probably you do, that it must be removed to do certain tests. I just wanted to state the engine requires it for those that might not know that.

To cure the running rich at an idle, I could only suggest that you change the idle air bleeds to a larger jet. I did encounter one V/4 looper whereas I had to experimant with the idle and intermediate jets to obtain a ideal idle with no hesitation when applying throttle. Good Luck.

Joe
"
 
" Joe, I was considering this

" Joe, I was considering this but wanted to be sure
that I eliminated all other possible causes for running rich at idle. Ok now the question is do I go up one size orifice at a time or can I make larger jumps. I have #16 in this 120HP now for idle air bleeds. Also should I touch the intermediate orifices or not? what RPM's is considered mid range?

please check out my posting in rec.boats for some detailed history on this motor and more info about my problem - I posted a few days ago. Do a search for "air bleed" and you find it.

thanks again Joe "
 
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