Johnson Evinrude 9.5 missing during idle

[Chris in Indiana]

OK, I've spent hours and hours tryingto get my 1967 9.5 to idle properly and am exasperated. It bucks and kicks for a while and then dies. The mixture adjustment has no effect whatsoever which is strange. Just the slightest bit throttle advance and it runs just fine though.
When I bought it the previous owner claimed he had just put in a carb kit and all new electricals (Coils, point, condensors.) I don't have any reason to doubt him given the appearances. I added a new water pump kit and thermostat. Any help would be apreciated! Incidentally it is only running 70 psi on both cylinders but that shouldn't effect idle performance right?

 

[F_R]

Re: Johnson Evinrude 9.5 missing during idle

Low compression will affect the idle. But going at this from a different approach, how are your motor mounts? Those motors are notorious for breaking mounts, and then it won't idle slow. Grab hold of the flywheel (not running, duh) and see if you can move the powerhead fore and aft. It should have some "rubbery" movement, but not flop around. If it flops the mounts are broken. Also, there are two vibration dampers, one on each side of the powerhead. They stabilize the motor and, again,it won't idle if they are missing or faulty.

 

[Chris in Indiana]

Re: Johnson Evinrude 9.5 missing during idle

Interesting reply, I wouldn't have thought about the mounts. When I got the outboard it was filthy so I took it completely apart and degreased everything. There was 1 broken rubber mount but I replaced it (Found a parts motor.) However, are the stabilizers you refer to the thin pieces of sheet metal floating on springs on the sides of the power head? If so they now have absolutely no lubrication and that may be causing trouble.

 

[mchin]

Re: Johnson Evinrude 9.5 missing during idle

My 69 evinrude 9.5 had similar symptoms and oddly after a carb re-build and all it still did it. what was missing was the little plastic cover over the carb opening. which i guess limits the amount of air going in, odd but it does. as the way i discovered this was by holding my thumb partially over the opening while the motor was idling. With my thumb covering it, it ran and idled perfectly, without, it ran rough and would hiccup and shudder. Of course ya can't go totally by my experience as the previous owner of my motor had the lower bellows gasket fully sealed off with silicone and tcut a 5 inch hole cut in the top of cover. He then added a computer fan grate to cover the user from the flywheel. it's butt ugly, but it runs like a champ.

 

[F_R]

Re: Johnson Evinrude 9.5 missing during idle

Interesting reply, I wouldn't have thought about the mounts. When I got the outboard it was filthy so I took it completely apart and degreased everything. There was 1 broken rubber mount but I replaced it (Found a parts motor.) However, are the stabilizers you refer to the thin pieces of sheet metal floating on springs on the sides of the power head? If so they now have absolutely no lubrication and that may be causing trouble.

That is what I was referring to. There should be friction pads in them that slide on the slots. NO lubrication, as that would destroy the friction qualities.

 

[Chris in Indiana]

Re: Johnson Evinrude 9.5 missing during idle

I'll have a look at them tonight, I do not recall anything non-metallic in that mechanism but wasn't looking to closely before either. I also want to double check and make sure I did put all of the rubber isolators back during reassembly.

My motor does have the plastic cover over the carb air intake. I have tried putting my hand over it but there is little effect on the problem. The engine will usually sputter and die, same reaction if I engage the choke. One strange thing, adjusting the mixture screw has absolutly no effect on how the engine runs except it is possible to get it so rich that it sputters at higher rpms. Perhaps it is not yet able to idle low enough to where that adjustment makes a difference. I have also suspected the plug wires and kill switch wires of faulty insulation and will replace both tonight.