DC magneto update

OK guys, here's a little good news, and some bad. I pulled the cap back off the mag, removed the rotor, and started cleaning with a tooth brush and electrical contact cleaner. After getting all gunk cleaned off the rotor, and checked the points again, I clamped the mag in my vice, hooked a jumper wire to the coil, and held the wire about an inch from the vice. NICE BLUE SPARK!!!
So... put rotor back on making sure to align the timing marks on gears, install cap, hook plug wires up and roll mag over. All have good spark. Now, I find #1 top dead center, turn mag until #1 fires, and install mag. I roll it over with the plugs out using the hand crank, all plugs fire. I removed the tappet cover and check valve adjustment. Turn fuel on, pull choke, and crank it over with the starter...NOTHING! It fired once, but never again.
So, I'm thinking its lacking fuel now? I even tried spraying carb cleaner into the air stack, but still only a quick pop or two. I guess I'll remove the carb, and start there.
 
Make sure you have the plug wires on correctly. Also make sure you are on compression stroke and not exhaust stroke.
 
agreed and when you install the mag it has to be set to JUST after it fires on #1 hole, move it no More,, sounds to me you are 180 out though
cnt
 
Barry: If you turn mag in vise and #1 fires, then install TDC, you are 1 out of time. Install in vise, and fire #2, which is 10 O Clock, then install so the next to fire is #1, which is 2 O clock.
 
Hmmmm....perhaps I did get it one impulse off... I will definitely check that as soon as I can get back at it. Due to a recent divorce, I have split custody with my 2 year old son, and he will be running around the house for the next 3 days, so tractor projects will be put on hold until Saturday. I am positive that #1 was at TDC, as I had the valve cover off and was watching the valves move.
Thanks for the advice guys, I'll keep ya posted.
FYI... I just ordered a new set of copper core wires and Auto-lite 3116 plugs this morning, will install them this weekend also
 
its easy to tell if you are one off, rotate the wires all one hole in the mag and try it, if nothing go the other way two holes and see if that works,
cnt
 
Make sure you have compression when both vales are closed. Hold your finger in the plug hole as the piston is coming up to make sure it is on the compression stroke.
 
If it's timed correctly and you got it to fire once, is it possible that you're spinning the engine over too fast? Found this a few times when starting with a 12 volt battery... the impulse mechanism is RPM sensitive so it's not wearing out at normal engine operation. Turning the engine over slower (use a 6 volt battery for example) or apply the starter in short bursts so you can hear the impulse clacking. The impulse is designed to give you a hot, bright blue spark during hand cranking but cut out once the engine is running and 12 volts into a 6 volt starter can be a problem.

Also, mine (DH, DV, DI) all usually need to be choked enough to be pretty rich and even have fuel drip out if they don't start right away.

Hope this helps.

Ken in AZ
 

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