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Carberator adjustments

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Wingnut2

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I just bought a Johnson 2R74E 2hp engine that had been stored for about 25 -30 yrs in a box in the attic. I took the carb apart and cleaned all the parts, everything was pretty much filmed over, but they all cleaned up good. I bought new gaskets and am in the process of putting it back together. I'm wondering what the settings are on the two (2) needle jets? How far to back them out after they seat?
Thanks, Dave
 
(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.
 
Thanks for the info on carb.

Now the motor has very little spark, not even enough to jump at the plug. I've taken the plug out and put a screwdriver in the plug wire end and turned the motor over with a drill and it still just barely has spark. I've had the flywheel off and the points look good. I was told the motor had less than 100 hrs on it before it was put away. Could it be the plug isn't any good or the gap at the points, or the condensor is bad? Where is the best place to start?
 
Rig a tester where you can set a 1/4" gap for the spark to jump... it should jump that easily. Could be a failing coil, points set wrong, bad condenser. Set point with flywhjeel key aligned with fiber rubbing tab of points so that a .020 gauge goes thru but a .022 will not.
 
i think your carb may require i nylon seat ,take the low speed needle out look closley at the tip with a flashlight look in the carb body does the taper of the needle match the carb if you see the old seat still there it can be removed with a dubble ought nitting needle it has a little hook on the end if you dont see one dont assume you dont need one they did have a tendesy to fall apart or left out if the last person who cleaned the carb. check with your local dealer the oem kit should come with one ask the oldest mechnic there to identify the low speed beering {or seat} he will know. as for the ign take the points off of the armeture plate clean with carb cleaner no petrolem lightly sand the plate and the bottom of the points make sure ground wire from plate to block is there reset old points this should take care of the problem.
 
These motors are famous for " bad ignition coils "-------------Most shops can test the coil on a ----------MERC-O-TRONIC ----ignition analyzer.
 
Thanks for the info. I'm gonna pull the flywheel, set the points and give the spark jump test a try. If it doesn't have a good spark then I guess I'll pull the coil and have it tested. And the condensor.
Thanks, Dave
 
you might try removing the points from the armeture plate clean throuhly with carb cleaner /no petrolium/ lightly sand bottom of points and armeture plats iv been quit sucesful with a good cleaning. saved lots of my customers money make sure ground wire from engine block to bottom of armeture plate is there, tight and clean if this dosnt help you my need to test coil. rember new points and codensor is easy on the pocket. need to know
 
I finally got back to the motor. I need to know what the points and plug gaps are. Anyone have the specs on it? I got the carb back together with new gaskets and am trying to see what kind of spark it has. Also, will it hurt the motor to run it with a drill motor to find out what the spark's like? It won't be getting any fuel/oil mixture.
 
Points are 0.020" and plug is 0.030"-------------------There is no need to turn it over with a drill.---------------With the magneto in good shape it will fire when you give the flywheel a good spin by hand.
 
I got it running today. Thanks for all the help guys. Now it looks like I need to either try to find an extention to make it into a long shaft or remodel the boat. The remodel will be alot cheaper. I priced a shaft and it cost $125.00 new. No telling if I can even find an extention? I've got the know-how to remodel the boat and I have the epoxy. The plans for the boat had a motor mount inside the console. Maybe a good job to do over the winter? Eccept it is so cold here, I don't think I would be able to work on it. North Eastern SD can tend to be brutal. We'll see, Thanks again for all the help.

Dave
 
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