Early 2082 with CH-18 fuel solenoid
 

I have an early 2082 with the Mag-20. I had the flywheel magnet let loose, so i put in a CH-18 out of a early 1864. I have been over the wiring diagram and am having issues. The fuel solenoid in the carb is suppose to be hooked to the engine connector to the blue wire that goes to starter solenoid and the violet wire coming from the alternator. I assume so that it has power to it for starting and then powered thru alternator to keep it open while running. If I hook up the wire that way the starter kicks in as soon as you turn key on. and don't shut off, because of the alternator feeding the wire to the starter, which makes sense to me. The key switch doesn't have a terminal that's both hot while cranking and hot while running anyone ever came across this before? I have it hooked to a hot wire when its running hopefully it will start tomorrow we are gonna get snow.

The fuel solenoid wiring in the 1864 has 2 diodes connected to it so it will not "backfeed" power from the alternator to the starter solenoid and cause the condition you speak of. If you add the diodes as shown from the 1864 in the polarity as connected, that should take care of the problem.

Attachment 71101

thanks frank never even thought that was what those symbols were duh! i no longer have the 1864. anyone know what size diodes they are i have a radio shack right up town where i could pick them up

I used some 1 amp that I had and they have worked for the last year

thanks guys

I'll toss this out as an option. You can remove the solenoid from the carb, cut the plunger off and reinstall it. Then you don't even need to worry about wiring it. BTDT :beerchug:

That engine runs leaner, which means hotter than your old Mag. I believe that solenoid is there mainly to prevent backfire when you shut down. I would keep it working and get the diodes.

You just have to let them cool down before shutting them off or pull the choke. Never had any problems with these 2 after cutting the plunger.

I cut my plunger in the 782 that I put a ch18 in, just because it's a tight fit to the gas tank plate and I didn't want to pull a motor to work on that solenoid when it fails. ( or take the carb off at best)I haven't heard a backfire yet:beerchug:

this one always has "run on" when you shut it off even when you let it run at idle for a few minutes. i have had the tins off and its clean under them.... it will run for maybe 5 seconds after key off sputtering and such then dies