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30 hp Johnson Idle and timing

A

arild_johannessen

Contributing Member
Have some questions about my 30 Johnson 2005mod. ( mod. nr: J30 ELSOD )

How many turns out on the idle mixture screw?

What should the timing deegrees be at Idle?

Thanks in advance
 
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For initial start up the needle should be out 1 -1/2 turn.----It must be adjusted after that for best idle and acceleration !-------The timing on these motor does not go out of adjustment unless the flywheel key shears.-----------What is your motor doing / not doing that leads you to ask these questions ??
 
racerone said:
For initial start up the needle should be out 1 -1/2 turn.----It must be adjusted after that for best idle and acceleration !-------The timing on these motor does not go out of adjustment unless the flywheel key shears.-----------What is your motor doing / not doing that leads you to ask these questions ??
Click to expand...

Its a stop screw fore the moving plate under the flywheel, suspect last owner has adjusted this one.
Clearly an adjustement here will affect idling speed I guess or?

Just trying to get a smooth idle.
 
The adjusting lockscrew on that rod is often adjusted because it appears to be " wrong " when it is correct.------At idle there should be about 1/4 ' or 6 mm gap.----Post picture of where it is now at idle.
 
The mixture screw is 1 and 1/2 turns out.-------This means that the motor will start and keep running at that setting. It is up to the operator to make adjustments once motor is warmed up.-----------Adjustment varies according to fuel used , elevation and local atmospheric conditions.
 
OK thanks, But another problem I just noticed , is that fore one crazy reason sometimes the engines start the WRONG way.
How is that possible? Have checked out flywheel and its key.
 
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Yes I did, nothing wrong there.
Suspect water coming into cylinder,either bad head gasket or leak at inner cover plate. one of the sparkplug is totaly clean,and it is much white smoke coming out of upper holes when running the engine
Guess extra high compression because of water in cylinder can be the cause why it suddenly starts the wrong way, agree?
 
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Do a compression test. Check for spark that will jump a gap of 1 cm on both leads.----Motor might be running on 1 cylinder.
 
Pulled the flywheel off once more, nothing wrong here. The surface on crankshaft and flywheel are very fine, no indication off something been out of its position here.
Noticed that both upper rubber mount are bad ,one off them has not the rubber there at all, and the engine are very unstabil when starting(electrick),could this make the engine start the wrong way?
I suspect an internal waterleak making high compression when starting, because of some water left in cylinder.
Engine runs like crap when cold, but suddenly idles smoothly when it gets warmer.
The starting the wrong way problem, is only when cold.
 
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Have now done the sparktest-good strong spark on both

Compressiontest ok -145 psi on cyl1
146 psi on cyl2

Also checked top of both pistons, normal buildtup dirt here, guess if the was a water leak,the piston top would been clean right?
The white smoke issue(a bit warm engine), probably bad water pressure from a worn impeller sometimes going the wrong way I guess.

I am a little bit lost here, what do you guys think, should I buy new upper mounts and see about the starting the wrong way issue,do not want to mount a new impeller before that issue is eliminated.
 
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Did a cylinder drop test: no difference at cyl 1, engine stops at cyl 2

Switched the coils : same result: no difference at cyl 1, engine stops at cyl 2

Also tried with other sparkplug wires and sparkplugs-same result: no difference at cyl 1, engine stops at cyl 2

Volt test : no charge from rectifier/regulator to batteri

Could a bad rectifier/regulator cause this?

I will try to measure the DVA-output on the wires going from cdi-box to coils. Will reply when done.
 
The motor is running on one cylinder as suspected.----Check the reed valves.-----" Strong spark " means nothing to me.----Does spark jump a gap of 1 cm , yes or no.--------The rectifier has to to with battery charging and nothing to do with spark for ignition.
 
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Think I found the fault.
Opened the wire connecter on the wires coming from under the flywheel going to cdi-box,was pretty corroded inside, did clean it well and now
the engine runs fine.
Tried another cylinder drop after doing this and now both drops at once pulled off.

Will do the cync-link adjustement/control, and reply.

Thanks a lot guys fore good advices.
 
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