1990 40 hp Johnson smokey pop cough!

[karlow1]

T-J40ElESF
This boat may have sat up for a couple of years (tag, carbs). When I first met Her, she would run if you squeeze the bub (VRO pump leaking gas). After getting her home she would only run on spray. Most of her life she was in salt water. She was very clean under the hood (WD40). The boat and trailer had salt water problems. I have patched her leaks, ground and painted the trailer, rebuilt her carbs, and set her carb floats. I have had her running on the muffs, and on the water twice. At idle, she is very smoky. she does not idle well, coughs sometimes. She gets a little better after warming up. (I took the carbs to work and blew it out with compressed air when I rebuilt them.) The first trip on the lake, she ran OK, a slight stumble coming off idle. It would only got up to about 4800 RPM, and was lightly loaded.
For the next trip, I adjusted the trim up to the next hole to bring the the nose up. I took her to bigger lake Pyramid (About 2600ft elevation). The reim is better. She is a solid ride in choppy water (1990 Tracker 17' Pro Deep V). This time she died at idle twice in the morning at the dock. She seemed fine off idle, the boat had about 200 more lbs in it as well. We ran at about 4800prm (not full throttle), she seems fine except at idle. When I dropped off idle she died, the problem is the idle speed is way too low. Later I had a hard time getting her to run again. She would just run a little and die. I pulled the cover, and had a friend crank her and I would open the throttle a little trying to get her to go, she would run a little bit, cough (or it might be a backfire) and die with a shutter.
We went back to fishing for a few more hours. When it was time to go, she was doing the same thing, but I managed to get her to go. She was very smoky, it turned out that she was trying to run on one cyl. After the 2nd cyl. kicked in she ran better just off idle. With that we popped on plane and ran to the dock wit no problems. She died as I slowed to an idle.
Back at the ranch, I ran her on the muffs. She is smoky and coughs. I tried to adjust the idle, I'm not sure if she gets a little better because of my adjustments, or she just because warmed up.
Latest test, I replaced two screw type clamps on the fuel line near the tank. I also did a vacuum test of the fuel line from the tank connection to the filter.
Her fule connection is good now, but I have not fired her up to see how smoky she is now.
I have ordered a manual. it will be here in a week or two.

Questions,
What should the timing be at idle (timing light)? There is a sticker that says 13degees BTC. Is this at idle or?
Should I be taking a second look at the carbs for the cough/backfire problem?
I adjusted the cam follower down (out) to open the carb slightly to get the idle speed up. How should the idle speed be adjusted? Prior to the adjustment, the cam follower did not touch the carb cam at idle.
What should the idle speed be?
Help!!!

[karlow1]

A little help please, anyone?

[tashasdaddy]

get a Johnson service manual, for your specific motor. blowing air thru carbs does not clean them. these are the directions for clean your carbs, any short cut, and you are wasting your time. i don't have a exact manual for your motor, so i will not comment on the timing.

[karlow1]

All of the removeable parts were removed. I used spray carb cleaner to clean the carb. It was clean except for the jet in the bottom of the bowl. There was a little crap there. I used the HP air hose at work to blow out all of the ports on the carb. I once cleaned a Honda 7.5 carb, and it did not fix it untill I blew it out with HP air. Now it's a std. practice. If you think that the carb is the likely cause, I can give them another run, but I do not know if I'm barking up the wrong tree

Thanks
KP