83 50 HP Johnson Not Running 100%

[robstead]

Hey all,

I recently awoke my 83 Johnson from its winter sleep after changing the fuel filter and all the fuel lines and it keeps bogging down on muffs, on the lever I have it on "fast idle" and it sounds more like a low stutter of an idle.

I fogged the engine before storing it so I'm not sure if it's just burning all that oil off from that and running too rich but there is so excess oil from the exhaust too, which I know isn't lower unit issues. Does it just need to be taken into actual water and cleared out or is there an underlying problem?

 

[ondarvr]

Check for spark on each cylinder, check compression, and clean the carbs, this should solve the problem or at least identify it.

 

[jakedaawg]

New plugs first.

 

[robstead]

New plugs first.

Will run out tomorrow and grab some new ones, they're less than a year old is possible that the fogging oil messed them up?

 

[boobie]

Drain the carb float bowls and flush out with fresh fuel. Then see what happens.

 

[jakedaawg]

Will run out tomorrow and grab some new ones, they're less than a year old is possible that the fogging oil messed them up?

Yes

 

[robstead]

Will try some new plugs tomorrow and emptying the bowls, really hoping I don't have to rip off the carb but have a feeling that is what it'll come to

 

[ondarvr]

Part of checking for spark includes looking at the plugs to make sure they do.

​Cleaning the carbs isn't difficult.

 

[robstead]

So went ahead and took it to the lake around the corner with me to run it with new plugs, had some trouble starting up but sitting in neutral it runs perfect, then when I started backing it down a little and it ran good but if I tried letting it idle, it would stall.

Started it again and there was a delay throttling it up.
Down the sides of the motor are still streaks of unburnt oil.
I'm assuming the carb is probably a little gummed up causing this, would I be able to run Evinrude 2+4 through it to loosen it up or am i definitely going to have to clean the carb by hand?

 

[ondarvr]

It's easier to clean the carbs than mess around with other stuff that might eventually help a little.

 

[robstead]

So cleaned the carbs and everything else today and it runs great but I feel as though my linkage is out of wack. I tried looking at the manual for the motor but the pictures are hard to see and compare to the actual motor.

Anyone have a common procedure/list to check to get everything back in sync? Only thing I touched was the linkage that connects under the flywheel and the carb linkage.

 

[robstead]

Anyone?

 

[Bosunsmate]

Ive this motor, i just check that the max advance is right with a timing light and the carb is then at full butterfly open.
I then set idle in the water when warm and that is that done perfectly for my liking

 

[juno pierrat]

disconnect carb linkage while idling, also maybe make sure carb roller and cam are not touching, does the idle change?

 

[robstead]

So had a mechanic come out and check the motor out, all the linkage is all synced and everything is good but he said it sounds like one of the cylinders is dead and there's spark there.

He mentioned that the reed valve could be bad, is there any way to check this myself? I noticed last time I had it running gas would spit out of the one carb.

The motor was running fantastic last season and seems weird that it would just cut out like this

Edit: added a picture down, the bottom hose is it possible that might have gotten clogged up? A couple of the valves feel like they have a little more give than the others but what is a sign that might be bad?

 

[Bosunsmate]

Did the mechanic do a drop test? That will tell you if a cylinder is dead
Put some wire up it if you a concerned its blocked

 

[marty53]

So cleaned the carbs and everything else today and it runs great but I feel as though my linkage is out of wack. I tried looking at the manual for the motor but the pictures are hard to see and compare to the actual motor.

Anyone have a common procedure/list to check to get everything back in sync? Only thing I touched was the linkage that connects under the flywheel and the carb linkage.

I feel your pain about trying to follow the link and sync procedure in the manual.... I have the same exact motor and going through the same stuff, except I have never ran mine on a boat. Going to try following the advice in this thread and see how i make out

 

[marty53]

Ive this motor, i just check that the max advance is right with a timing light and the carb is then at full butterfly open.
I then set idle in the water when warm and that is that done perfectly for my liking

This sounds like good advice, but the one thing it doesn't explain is how to set the adjustment barrel on the rod between the spark advance lever and the carb linkages. This is the part I don't understand, and that the factory service manual does a horrible job explaining. I have 2 marks on the cam roller, the top one says "start" but i have absolutely no idea how this is supposed to be set up.

 

[Bosunsmate]

Post some photos and il try and remember. I think its something like the butterflys should begin to open when one mark hits the butterfly opener thing. Dont worry about that too much. The main things a your low idle and your max advance. Too much advance and you will burn up your cylinders. When you use the warm up lever when its cold it will give the right amount of advance of spark when operating the choke by pressing in the key.
Remember that spark retard is how the motor idles and then spark advances past 0 to be ahead of the piston timing to increase engine speed and it is the opening of the butterflys and thus throwing lots of fuel down the engines mouth that brings on the last main proportion of power

 

[robstead]

Did the mechanic do a drop test? That will tell you if a cylinder is dead
Put some wire up it if you a concerned its blocked

I ripped the reed valve off and it was fairly open, seems the lack of back pressure towards the carb was making it run too Rich and was flooding the one cylinder over time as making it just not fire.

As far as pictures go, maybe you can make something out of these and lead us down the right path

(This is with the throttle lever DOWN)