1981 Johnson 70hp idle?

[Puncheon50]

I just got a cheap barn find. It has a 1981 Johnson 70hp on board. It has an electric choke and a high idle start bar. The motor starts up with the start bar engaged and will continue to run as long as the start bar is engaged. The problem is the bar will not go down all the way without flooding the engine. I can slowly move the bar down to a decent idle but the bar is not all the was down which does not allow me to shift into gear. When I put the bar all the way down, the engine seems to flood and I have to wait a few minutes to start again. I have an aftermarket Seloc manual, but I am having a difficult time finding this particular issue to troubleshoot. Any help would be greatly appreciated

 

[racerone]

I doubt that it is flooding out !-----Best to start with posting the compression numbers of this motor.

 

[Puncheon50]

Ran engine to warm up. Killed the gas line. Top Cylinder 139 Middle 132 Bottom 141

 

[Puncheon50]

I meant it kind of behaves like it is flooded out. it will stall when I put the starter bar down and it won't start back up until it sits for 3-5. Minutes

 

[Puncheon50]

So digging into my problem, the high idle start bar is part of the primer system and when engaged the the engine is running rich. When I put the bar down the engine dies so I am guessing the fuel system had a restriction somewhere or is this more of primer solenoid or idle adjustment

 

[racerone]

The fast idle lever is NOT part of the primer system.----The primer solenoid was not installed at the factory on 81 models._---What is the model #----The electric primer was first installed on 83 models of the 70 HP.

 

[Puncheon50]

Model # J70ELCIM I was just going by what I was reading in the Seloc manual.

 

[Puncheon50]

Just looked, yea, there is no solenoid like the one in Seloc

 

[racerone]

The SELOC manual are not always the best.-----They can be useful in the wee house with the half moon in the door.

 

[Puncheon50]

So if the start bar is acting as a true choke, when I put the start bar down it is killing air intake? Would the slow speed idle adjustments need tweaked or is there another adjustment on or near the choke level that would make the adjustment?

 

[w2much]

Did you clean, soak and or rebuild the carburetors on this barn find? It needs to be done. Are you speaking of the fast idle lever on the control box? If so you may only need a cable or idle speed adjustment. The key switch pushed in is your choke.Pull off your cowl, turn on the ignition and push the key in. Do you you see or hear anything. If so tell what is happening.

 

[racerone]

The " start bar " is NOT a choke at all on this motor !!!-----It just gives motor throttle without shifting.-------The choke is activated by pushing the key in while cranking it over.----Best to get a real manual as the guessing is not working for you.

 

[Puncheon50]

Two spring Screw adjustments that regulate the swing of a bar that is linked to the throttle and start bar. Upper one I believe is high end and bottom one for idle. Neither set screw is touching the bar whether the bar is engaged or at full throttle or in neutral. Unfortunately, I don't mean to beat a dead horse, but the Seloc manual shows a single idle screw and a different arm bar. I believe that the lower screw is to adjust the idle and the screw does not engage the bar at all when it should at minimum idle. Am I on the right track here and shouldnt the upper screw be engaged at max rpm as a safety to not over rev the engine? I tried to upload pics but this website is stuck in 2001

 

[racerone]

?----Others manage to post pictures.

 

[Puncheon50]

Says file over 2mb Anyways, that was my issue. Someone fiddled with the lower .idle setting and popped the nut out of the holder. They couldn't figure outout how to compress the spring and nut to reset the bolt correctly. Anyway once I got it on there correctly it was a matter of moving the bolt to bar as I decreased the rpm with the idle start bar. Works good now. Onto the next issue but if anyone has an idea on the best way to adjust the top end I would appreciate it

 

[JerEazy]

X2 on rebuilding and soaking the carbs. Gunk/restriction will “idle” with the fast idle lever pulled but won’t run under normal conditions. easy job and should be preventative maintenance on older 2-strokes along with T-stat and water pump.

those parts are too important to wonder when they were last done.