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Help. 1956 30 hp johnson has me stumped....

C

cjbrill715

Regular Contributor
Can't seem to get this engine running. 120 psi both cylinders. Excellent blue and snappy spark. Fuel pump conversion, carb rebuild, new fuel lines, etc......When i prime the bulb, the carb is filling up fine, and i pulled the low speed needle and it is wet with gas, but when i pull the carburetor, and look into the intake manifold at the reeds, it seems to be awfully dry in there, like it's not getting any fuel past the carb. It won't fire, so i'm assuming it's a fuel delivery issue....any input would be appreciated!
 
The low (slow) speed adjustable needle valve is wet?? How can that be?... The slow speed needle valve is the top needle valve.

Your mention of the above make me wonder if you have the needle valves mixed up. The top needle valve (slow spewed) is the one with a long tapered tip to it. The bottom needle valve would be the one with a shorter beveled tip to it.

The initial carburetor adjustments and the final adjustment procedure are:
********************
(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top 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. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, 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.
********************
 
joereeves said:
The low (slow) speed adjustable needle valve is wet?? How can that be?... The slow speed needle valve is the top needle valve.

Your mention of the above make me wonder if you have the needle valves mixed up. The top needle valve (slow spewed) is the one with a long tapered tip to it. The bottom needle valve would be the one with a shorter beveled tip to it.

The initial carburetor adjustments and the final adjustment procedure are:
********************
(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top 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. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, 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.
********************
Click to expand...

Yeah, it's the low speed, long tapered and on top...and it's wet....And my initial settings were similar to what you said. The motor probably hasn't been started in 30+ years....Are they typically difficult to start when everything beyond the reeds is dry??…It has a little WD-40 in the cylinders though
 
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Motor should start right up with about 3 pulls on the recoil.------Are you turning throttle against the neutral interlock for starting ?------So something is wrong.-------Does spark jump a gap of 5/16" , yes or no ?-----Wires on the correct plug ?-----What is the high speed needle set at ?
 
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racerone said:
Motor should start right up with about 3 pulls on the recoil.------Are you turning throttle against the neutral interlock for starting ?------So something is wrong.-------Does spark jump a gap of 5/16" , yes or no ?-----Wires on the correct plug ?-----What is the high speed needle set at ?
Click to expand...

I have the throttle handle turned to the "start" position...When the shifter is in neutral, the base plate has a stopper tab that keeps it from advancing past a certain point. I haven't done a spark gap test yet, mainly because it is looking like a fuel delivery issue, and the spark at the plug is bright blue, and produces an audible "snap". Wires are on correct plug. High speed needle was around 2 turns out from seated position.....Like stated above, the motor hasn't been started in atleast 30 years, and it's dry from the reeds through the bypass all the way to the cylinder....So i'm wondering if it's simply needing to get fuel through it...Not sure if pull starting creates enough vaccum when a motor is that dry?? Doesn't a motor generally start off residual fumes, and then the vaccum force of the pistons actually running draw in gas from the carb??...I'm trying to learn, not trying to be difficult
 
Have some pre-mix fuel/oil in a spray bottle and spray it directly into the carburetor throat with the throttle wide open as a priming shot.

Have the throttle grip turned as far as it will go with the shift in neutral... not just to the start mark. Those readings are on a clip plate mainly just to hide the two retaining screws and to remind you which way is off or fast.
 
joereeves said:
Have some pre-mix fuel/oil in a spray bottle and spray it directly into the carburetor throat with the throttle wide open as a priming shot.

Have the throttle grip turned as far as it will go with the shift in neutral... not just to the start mark. Those readings are on a clip plate mainly just to hide the two retaining screws and to remind you which way is off or fast.
Click to expand...

Alright. I'll try that tomorrow. Thanks!
 
joereeves said:
Have some pre-mix fuel/oil in a spray bottle and spray it directly into the carburetor throat with the throttle wide open as a priming shot.

Have the throttle grip turned as far as it will go with the shift in neutral... not just to the start mark. Those readings are on a clip plate mainly just to hide the two retaining screws and to remind you which way is off or fast.[/

Quick question....How did they "kill" that motor??....It doesn't seem to have any aparent kill switches anywhere...Did they just pull they choke briefly??
Click to expand...
 
Normally, if there was no remote control setup... and all there was, was the engine with the tiller handle and a manual starter... there would be a rubber push button that would kill the ignition when pushed.

The wires that would lead to that push button would be two black wires leading down from the magneto armature plate, one wire from each condenser retaining screw. Pushing the button would connect the two wire, shorting out the points, and effectively killing the ignition. Those two wires could of course also lead to a On/Off switch on the dash, etc etc.
 
joereeves said:
Normally, if there was no remote control setup... and all there was, was the engine with the tiller handle and a manual starter... there would be a rubber push button that would kill the ignition when pushed.

The wires that would lead to that push button would be two black wires leading down from the magneto armature plate, one wire from each condenser retaining screw. Pushing the button would connect the two wire, shorting out the points, and effectively killing the ignition. Those two wires could of course also lead to a On/Off switch on the dash, etc etc.
Click to expand...

My motor is just a pull start setup with no remote setup or wiring, and not even a gear on the flywheel for a starter, just a tiller handle setup....Is there a kill switch setup that i could make for this?....Or better yet, how did they kill this motor with this setup originally??
 
'56 did not have a stop button. You simply turned the throttle down so slow thaat it stalled. Stop button first appeared in 1958 and can be rerofitted, but not really necessary, unless you desire an lanyard kill switch.

That HS needle open a couple of turns is way, way too far. It should be flooding like crazy at that setting. 1/2-3/4 is more the norm.
 
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