Pamco coil test fail question.

[little_ryle_13]

OK this is my first 78 XS and first Carb orator powered anything. On top of first pma/pamco system I've dealt with and I'm kind of stumped. With that said I rode the bike for three hours the first day I got it and it died on me at a traffic light. Pulled off tried to get it to start back up and nothing. Changed spark plugs again nothing. Next day pulled the carbs PO surprisingly cleaned them, but I took a stab at them anyway. Put them back on bike would fire up but die after a few seconds and immediately when given gas. The wiring was a little cruddy and not much to it so I rewired it today. It finally ran for a minute today could give it throttle but backed fired a little. So in the time it was running we noticed it wasn't firing on both cylinders just the right side. Swapped plugs around but couldn't get it to run long enough to see if the left side was firing now and not the right. So I tested the primary ends on the coil and got 4.5 ohms which I've read is correct. But when I tested center of plug terminals it didn't read anything. Also tested from primary to center of terminal. Got nothing. So my question is is my coil bad? I searched for similar problems like mine but didnt find a definite answer. Anymore ideas at what it might be.

 

[Reid]

Are you sure that your charging system is putting out voltage? I have had a similar problem in the past turned out to be not charging the battery and would run until the batt votage dropped. Its a good place to start

 

[scabber]

Sounds like the timing might needs to be checked. Did you install the pamco correctly? I would check to see if all of the trigger magnets are in place. The coil Fires the bike If it was bad I don't think it would run at all.

 

[little_ryle_13]

I didnt install the pamco PO did. and it ran fine 3 hours up into the point it died on me. Just swapped out the battery and still no luck. Still troubleshooting.

 

[pamcopete]

little ryle 13,

Try running with the PAMCO temporally wired directly to a battery with the PMA regulator unplugged.

 

[little_ryle_13]

Ok Pete I just did that and the bike ran could throttle up. Ran as good as it did before it broke. So does that mean that it is the PMA?

 

[pamcopete]

Ok Pete I just did that and the bike ran could throttle up. Ran as good as it did before it broke. So does that mean that it is the PMA?

Well, the PMA's are pretty rugged, so I would suspect wiring or the regulator. Do you have a wiring diagram? Is it a capacitor only setup? Be careful when doing these tests that you do not leave the PAMCO powered up with the engine not running.

 

[little_ryle_13]

I didn't have a wiring diagram when I rewired it. Just followed what PO had. Here is what I came up with as far as the wiring though. This is all I have on it.

 

[Austblue]

You do have the green wire coming out of the rec/reg grounded right? Not shown that way on the drawing is all but it should have a red to your battery positive and a green or black to the negative/ground.

 

[little_ryle_13]

oh sorry yes I have a red green and black coming out of my reg. the red and black are tied together. And the green tied into the ground. Updated diagram below.

Edit: sorry now it is up

 

[little_ryle_13]

Is there a way to test the reg/rec without the motor running?

 

[Reid]

Make sure the regulator wires are cripmed well. After trying everything else I pushed the wires out of the plug, recrimped and soldered. No issue since

 

[little_ryle_13]

Well this particular reg the 6 wires coming out of it have epoxy resin holding them in like it was made like that. I have checked the all other connections though.

 

[little_ryle_13]

Figured it out the advance rod had gotten bent somehow. It didnt have covers on it when I got it. So something may have gotten in there and caused it. But swapped it out runs like a champ.