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1959 Johnson 35 HP won't start

C

Clint1395

Contributing Member
This motor ran great last year after i replace the all electrical and rebuilt the carb. Tried to start it yesterday and it just won't start. It still has great spark and i cleaned the carb again just to be sure. I can't even get it to fire if i spray gas straight into the intake. Also it has good compression. Is it possible for the plugs to spark outside the cylinder then not spark inside. Or is there anything after the Carb that could stop fuel? Thanks in advance.
 
Have you had the flywheel off? If so, did you torque the flywheel nut to the specified torque setting? If not torqued, the flywheel key will shear (throws the engine out of time).

I assume that you have compression on both cylinders?

With plugs removed, the spark must be able to jump a 1/4" to 3/8" gap with a strong blue lightning like flame... a real SNAP! Does it? Note that checking spark by using the spark plugs is a waste of time! The 1/4" to 3/8" gap is important.

If you have compression and spark, that leaves fuel. Make sure there's no water in the fuel... and double check that carburetor work.

(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.

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http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
I'm gonna check the flywheel key. That's the only thing it could be at this point. I did pull it and didnt have a torque wrench so I tightened it to German specs (good and tight).
 
I took it off and the checked everything. It looked good. I'm at a loss. I can normally make just about anything with pistons run. I'm gonna check compression again but it feels like it always has. What is in the intake manifold? Does it have reeds. Could these block fuel. It acts like its getting no fuel. Even if I squirt some straight in the carb intake. Any suggestions? And... My starter is on the downhill big time. Where can I get a rebuild kit? I couldn't find a "kit" in the parts on this site.
 
Clint1395 said:
I took it off and the checked everything. It looked good. I'm at a loss. I can normally make just about anything with pistons run. I'm gonna check compression again but it feels like it always has. What is in the intake manifold? Does it have reeds. Could these block fuel. It acts like its getting no fuel. Even if I squirt some straight in the carb intake. Any suggestions? And... My starter is on the downhill big time. Where can I get a rebuild kit? I couldn't find a "kit" in the parts on this site.
Click to expand...

The intake manifold has circular type leaf valves (reeds), nothing there to block fuel.

Have some premix in a spray bottle and shoot some of that into the carburetor throat... open the throttle butterfly first of course so that the fuel gets to the intake manifold leaf valves. If this results in having the engine fire up, I think it would be a good idea to rework that carburetor... something was overlooked.

Do you for a fact have spark as I described it in an above reply?
 
Ok. Spark would only jump an 1/8 inch gap. But I've hot new coils points and condensers. How exactly doin gap the points?
 
Stupid me replaced the plugs and it fired. I'm an idiot. But now my yearly maintenance on it is done. Thanks for the help guys!
 
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