9.9 johnson no idle and choke on restart!

[whistler66]

Sorry I don't know the yr as I'm posting for a friend. This is a grey Johnson with grey, black, maybe some white in the name decal on the cowling. I don't think it over 5-7 yrs old? Has had constant trouble with idle. Had had carb rebuilt 3 times. 2 times in the last 6 months by a reputable dealer. Each time dealer blames bad gas? Friend mixes gas properly and uses a high tier brand gas. His boat is used enough that he shouldn't be having an "old gas" problem. The 2nd time he had the Carb rebuilt it did set for a month prior to use and then it would'nt start at all. Another trip to the shop got another rebuild.....but still a no idle. I had failed to mention this machine had almost refused to idle from early on as my friend has owned it since new. It might idle occasionally but not often. This has not been a bother to my friend as the way he uses it! Starts it, travels to point A......lets it die and anchors off.....Then repeat process to point B if fish are not biting etc.. It will start on the coldest mornings in no more than 2-3 pulls and run as long as some throttle or a little choke is given. I guess what I'm saying here is it's not any more cold natured then any other outboard I've been around and a lot less than some! Even after warm-up with no choke it will not idle at all period! After dying It will restart on the first pull with full choke. With no choke it is a multiple pull and pray operation!!! He is used to this procedure and can manage with little bother but let someone not used to it operate it and it is a headache. Got any suggestions. Please be elementary as I am very limited in my boating basics! In trying give enough info I probably confused some...... Sorry. Thanks in advance for any suggestions!

 

[stanky]

Re: 9.9 johnson no idle and choke on restart!

There are no doubt more qualified people who will respond to your question than me, but I can tell you that I had the exact same problem on my motorcycle and it turned out to be a clogged idle jet. Maybe your friend needs to clean the carburetor one more time and put a filter on his fuel line?

 

[tashasdaddy]

Re: 9.9 johnson no idle and choke on restart!

we really need a year or model #. i would check spark on both cylinders, with an adjustable spark tester, and compression. the motor should idle in gear at +-650 rpms. can check with a timing light w/ tach function.

the motor does have an adjustable low speed jet, # 15 on the parts diagram http://shop2.evinrude.com/ext/index.aspx?s1=bf6ad09c53cead335fcfd8a6471c0f7f

it needs to be adjusted:

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.