Electric Gremlins - Tested Ignition Coil, Rectifier, Relay, Pickup Coils

steest

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Hello, I am working on my wife's bike. It is a 1983 400 Maxim DOHC. When she bought it last year, it ran fine for about 10 minutes each time and then would die until the bike cooled down. This spring I tried getting it started and it would not start. The the right ignition coil would not spark.
- Swapped entire right ignition coil(with plug and wire) with left. The right side would still not fire.
- Noticed that when I turned the key off the left side would spark
- I tested the pickup coils and they seemed good
- I tore into the TCI
- replaced transitors, capacitors, and reflowed solder joints
- side note: I did notice that some connections where soldered togethered on the back, I assumed this was just shoddy workmanship but now with my resulting issues it may have not been

Put the TCI back on. Now when I hit the start button, the starter does not turn over right away. Still have spark on the left but not on the right.

So time for some more testing:

Fuse block - bypassed main (corrosion, did not have continuity across fuse. I jumpered this)
Battery - 12.78 V
Starter Circuit Cutoff Relay
- SkyBlue - BlackYellow -Spec 50 ohm Actual 80 ohm
- Test Relay - Apply 12v to RedWhite and BlackYellow - RedWhite and RedWhite should be connected. This is not happening, it remains open, but lights turn on in dash and headlight comes on, with key OFF
- For relay diode test, electricity will flow both + to - and from - to +, either way I get an ohm reading
Skipped alternator tests
Voltage Regulator - Engine not running
- V1 Main switch off - Black to Green - 0V
- V1 Main switch on - Black to Green - .82V
- V2 Main switch off - Black to Brown - 0V
- V2 Main switch on - Black to Brown - 8.35V - Manual says should be less than 1.8V
- Could not check the silicon rectifier diodes, could not get the regulator off its mounting plate
Ignition Coils (My coils do not look like the diagram)
- Left Coil
- Primary - Orange to Red/White 2.6 Ohm - Manual Spec 2.75 Ohm
-336 MOhm - Manual Spec - 7.9 MOhm -KOhm
- Right Coil
- Primary - Orange to Red/White 2.8 Ohm
Pickup Coils - Manual Spec 120 Ohm
- Black to Gray - 119 Ohm
- Black to Orange - 145 Ohm

1. So, it looks like my rectifier, relay, and possibly TCI are bad. Are there any other tests I can do to confirm?
2. Since the TCI unit is unobtainable, is there any aftermarket systems that are compatible? I was looking into the Pamco units, but it appears only the SOHC engine models are supported. Is there a conversion that is possible?

Thanks for any input!
 
Hi steest
Battery should be more than 12.8 V. More like 13.i
The starter is nothing to do with ignition system but is dependent on battery condition
Start with simple stuff - get a new battery or use jump leads from a car battery
Then pull the plugs out, get someone to hold them against the engine (carefully ) and see if you’re actually getting a spark on the right side.
If not, slowly track back through the wiring looking for voltage to the coil.
I’m not sure how the TCI is connected, but see if you run the right coil off the left side output from TCI x at least that will check the downstream wiring
It won’t be all those things you’re looking at, I’d recommend a more logical approach
Good luck
Gra
 
Did you replace the battery before you did any of this?

Remove the spark plug boots from the wires. Is the wire intact? cut a 1/4" or so off the ends to get some fresh wire in there.

My bike has points ignition so cant really help you there.
 
My 82' Seca which I believe uses the same/similar TCI had the same problem. No spark on left, coils, pickup, caps, and plugs all within spec and worked when switched to the other sied. I saw some potential water damage inside the TCI when I opened it up and decided to replace it; lucked out and found one on ebay and when I plugged it in, it worked like a charm. This may not be what you want to hear, but it probably needs to be replaced. You'll have to keep an eye out for one on sale, or try to work out an aftermarket solution unfortunately.
 
I have the exact same bike and I'm having either a TCI or pickup coil problem, so I ordered an aftermarket TCI from ignitech ($179 on my doorstep) but I went with the programmable one so I can't test it yet, does anybody know where to find pickup coils for this bike?
 
My 82' Seca which I believe uses the same/similar TCI had the same problem. No spark on left, coils, pickup, caps, and plugs all within spec and worked when switched to the other sied. I saw some potential water damage inside the TCI when I opened it up and decided to replace it; lucked out and found one on ebay and when I plugged it in, it worked like a charm. This may not be what you want to hear, but it probably needs to be replaced. You'll have to keep an eye out for one on sale, or try to work out an aftermarket solution unfortunately.

I highly recommend an aftermarket solution as I only found one OEM TCI on Ebay for $600, that's more than I paid for the bike in the first place!!! Ignitech offers plug and play TCI's for this bike and even a programmable option for like $30 more, and both are plug and play with no custom adapters needed, but the programmable one doesn't come programmed so you'll need to use the software they provide before you can hit the road.
 
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