1989 Yamaha 200HP - No Spark on Port Bank

[still_bill]

I have a 1989 Yamaha 200HP Outboard (200ELG) on a 1989 Master-Craft Barefoot Special.

No spark on Port bank (3 cylinders). Have replaced stator already, but no change (both new & old test OK).

Suspect CDI box, but don’t want to spend $$ in case it is something else like trigger/sensor coils.

Was running perfectly until recently. Need suggestions.

 

[still_bill]

Well, to answer my own question - it is NOT the CDI box. I replaced with known good one, and problem persists.

 

[still_bill]

Update. It was not Stator, CDI, or Pulser. I found a coil that tested bad on the side that was not working. Swapped that to good side, now I have spark on Port cylinders. Not sure how one bad coil could make others not work, but it happened. Just ordered 6 new coils from eBay ($26 each). If I don't post again, then assume it is fixed!

 

[still_bill]

Well, ignore my previous post (if anyone is watching). It was not correct. Not the coils (6 new installed). Thinking now that it is the ignition control module (not CDI).

 

[KyBullet]

Well, ignore my previous post (if anyone is watching). It was not correct. Not the coils (6 new installed). Thinking now that it is the ignition control module (not CDI).

That's what I would lean more towards

 

[still_bill]

There is a "Control Box" below the CDI which seems to be only for limiting the rpm to about 2,000 if engine overheats. Overheat switches and buzzer work, but disconnecting the pink wire to Control Box made no change. Swapped Control Box with Used unit - no change. In fact, with the Control Box totally disconnected there is no change (spark on Starboard side only).

Now the weird part: If I disconnect all 3 Starboard spark plug wires, the engine will start on just the Port cylinders! Plugging the Starboard plug wires back in while running has no effect - it runs on Port side only until shut-down, then it goes back to Starboard-only on next restart. I'm thinking maybe the used Control Box is also bad? I suspect the Control Box rather than stopping one bank during overheat, supplies a ground to second bank if no overheat. I found that putting a jumper across the bottom 2 wires on CDI (black and brown to Control Cox) fires the dead side briefly when jumper is removed.

Next, I am going to try another used Control Box. Maybe replacement was same bad as original? Any other suggestions would be appreciated.

 

[flyingscott]

do you have a shift interrupt switch?