Honda CB360 big bore engine: no spark

[Nickel89]

I've been piecing together a CB360 big bore engine, 383cc now. She's all ready to go, apart from the fact I can't seem to get a spark from it.

Found a donor engine, taking the old engine out, swapping things like the Pamco ignition straight over. Dyna Coils are entirely new to the bike, but I've checked with Dynatek technical support, and they seem okay. Ever so slightly expecting the Pamco to be faulty (didn't miss a beat before) or I might've messed up somewhere else.

Just don't know how to measure what where. It's a custom wiring loom I had made years ago, but the dude who made it seems to have vanished. So no wiring diagrams.

Sort of the current state, for about two weeks now... can't seem to get my head around it. She's got compression a plenty (kickstart only; great idea) and smells like she's getting fuel too. Just won't set it off.

Anyone got an idea? Because I'm lost here!

Big bore engine mod list:
- 383cc big bore
- Custom stainless 2-into-1
- Mild headwork
- Flushed head
- 10.5 : 1 compression
- Kibblewhite racing spring and titanium retainers
- New valves
- Mikuni VM30 carburetors
- Domino quick action dual pull throttle
- K&N pods
- Gearbox etc. superfinished
- Dyba Coils
- Pamco digital ignition
- Reg/rec upgrade
- Starter motor removed
- Plain bearing shifter mod
- Lubrication mods
- Clutch mod

 

[teazer]

Are you getting a spark? take the plugs out and lay then against the motor and kick it over and you should see and hear the spark. Even better are a pair of cheap spark testers with a large enough gap. With those you can hear a Zap that should put a murder hornet into fear for its life.

Adjustable High Energy Ignition Spark Plug Tester Pick Up Coil Diagnostic Tool | eBay

Adjustable High Energy Ignition Spark Tester. (S/E): standard ignition minimum spark gap indicated by "S". Checks for any spark in no-start condition. Designed to prevent high energy sparks arching directly to any ground.

www.ebay.com

There are lots out there. I use some even cheaper ones that came from an Autoparts store.

 

[irk miller]

Make sure the PAMCO E-advancer is grounded.

 

[teazer]

Good point.

 

[Nickel89]

No spark at all, no. Plugs out against the cylinder head, tried different boots, different plugs. Nothing.

Going from irk miller's comment, I've taken the Pamco pick-ups off. Had a bit of an issue with routing the wiring before, might've jiggled something loose... Out comes the multimeter again.

 

[Nickel89]

Right, so I tested all the wires off the pick up for resistance. They all vary, but from one pick up unit part to the next, the Ohmage is the same.

So that would rule out a broken connection there. Would anyone know what kind of voltages I should be measuring with the ignition turned on? Also where exactly? Got green, red, and black wires.

I'm not exactly an electrical engineer, but I'm trying

(Obvious product placement for the employer there ✌)

 

[irk miller]

When installed, the sensor should be letting total voltage (minus a few tenths for voltage drop) to the coils. So, you hook the positive lead on the meter to the wire from the ignition module to the right coil. The negative lead on the meter is hooked to frame ground or the negative terminal on the battery. Turn the engine over until magnet passes the right sensor at which point you should get 12 point something volts. Do the same thing for the left side. Normally, this is a blue and yellow wire. I can't remember what color the PAMCO uses. Now, as far as the ohm readings, the Dyna reads OL or infinity on resistance from negative to either coil lead from the Dyna sensors. Make sure the PAMCO shouldn't be the same. If you are getting resistance, I suspect that may be your issue.

 

[Nickel89]

Ditched the starter motor (because race bike) already, so that sucks.

Larry from Dynatek is also running out of ideas, suspecting the Pamco's to blame. Is there some sort of Pamco fault finding manual out there?

Pamco Pete isn't active on here anymore, is he?

 

[Sonreir]

The way to test the Pamco unit is to measure resistance between the trigger wire and the battery negative terminal. You should get a reading close to zero. While continuing to monitor resistance, rotate the engine (by hand) two full rotations in the counterclockwise direction. At some point, you should notice the resistance reading go to Open Line and then back to zero. Repeat with the trigger wire for the other cylinder.

I'm assuming the trigger wire is green, but I'm not certain. Do you have any documentation?