CB350 Pamco Ignition System Troubleshooting


Been Around the Block
Hey all,

After starting up my CB350 for the first time in a few weeks, I discovered that the right side cylinder wasn't firing. After a bit of digging around, I ended up verifying that it wasn't fuel flow, and was about to check my plugs when I noticed water dripping down onto my toolbox. Opened up the seat to find my electronics tray completely flooded and turned into a big block of ice. Battery is a shorai, so that should be fine. Regulator/Rectifier wasn't in the electronics tray, so that was spared. All the fuses are fine (surprisingly enough. The only thing that is a real concern is the Pamco ignition box was in the water. My guess is that it's fried, but I don't want to buy a new one without testing it to make sure first!

SO, what are my steps. Obviously first I'll want to test to make sure I don't get a spark on the plug with the non-firing cylinder.
Second I'll want to test that it's not the coil (just swapping the wiring for coils, correct?)
Third I'll want to test the ignition. How would I go about this? Seeing if it's the Hall Effect Sensor or the Ignition box or both?

Most I can think of currently is just trace 'em and make sure nothing came loose, but with the circuitry and it being in the water I'm guessing it's likely shorted. Am I stuck just making sure it's not the coils and then getting a new ignition?

Thanks all!
take the module out and shake it all dry

blow it off with air if you can

then buy a one pound bag of rice and put the module in a bag of rice for a day

then try it again
Will do!

I know that's usually only relevant if you're avoiding damaging the circuits via short, though. In this case, as I've already run the bike, power has already gone through it, so the damage is likely done. :-\

I'll definitely give it a go, though. I'd love to save buying a new one.
What would switching the plug wires show? If it was something up with the plugs?

One option I'm realizing would be to switch the wires going from the ignition to the coils.
Switching plug wires will show if you have a carb issue. If the same cylinder doesn't fire, it's not ignition, but is fuel related.
If opposite cylinder is dead, then it's ignition related.
Ah yes, that was already resolved in my head but it's a good idea to check. Carb definitely has fuel, there's definitely suction, and the carbs (round-slide, not cv) are lifting properly. Bike also ran great 2 weeks ago, and I use low ethanol fuel from a independent gas station, so I very much doubt the jets are fouled in any way. BUT, still good to verify!

After verifying it's not fuel, though, what would y'all suggest? The manual's troubleshooting steps don't really relate to this, as the ignition is completely different.
You may try getting in touch with Pete from Pamco for some test procedures.

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I wish I could help but sadly after burning up 3 pamco units on my xs650 with no reasonable explanation for it I robbed the points off a donor motor and haven't looked back.

Pete was kind enough to replace it twice and through all of my work and trouble shooting I never found the culprit and decided it wasn't worth the hassle.

This bike was originally a tci ignition with a bad pickup coil which is why I went with pamco keeping it electronic ignition, but in hindsight I wish I had converted to points from the start.

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Ah shoot. I'm loving the electronic ignition. What were your symptoms of burning them out? I'm getting some spark on the right side as well, but it's backfiring like mad. Wondering if that's a symptom of something else or if the ignition is misfiring.
I had no spark at all... completely dead. Burn mark under the circuit board on the rotor back plate.
After the second one I picked up a ballast resistor, a capacitor, got the points set up, and haven't looked back.

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After a couple of mid high Rev pulls of only a few seconds(like maybe 5,500-6,500 rpm) it started to break up then it would act like it was running on 1 cylinder for a while before it would completely die...all within about 30sec to a minute.

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Good to know. I'm gonna diagnose further. The circuit board looks fine. Looks like the right side plug was completely fouled. Cleaned that up and the right side is firing now, but is backfiring quite a bit. Might just need to be run a bit, but I also have new plugs I'm going to put in.
Well then it sounds like it's still working for you. Goodluck finding the issue with it. Fingers crossed!!

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Yep. Took it all apart, and sat it in front of a hair dryer for a while (not too close, and not on the hottest setting!), and then put it back together. Turns out me running it with all that water in the electronics tray caused a ton of misfiring still, but didn't break the ignition. It DID foul the plugs, though, which just confused things. Replaced those and we're back on track!
it is not about being right and so you know i m not giving you crap

the part that was important was by not drying it properly you further risked the components every time you powered them up

dry that stuff out before powering it up

i will go shut up now glad it worked out for you
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