Been doing a lot of reading trying to make sense of this issue, if anyone can help clarify it would be fabulous....
Heres the beef....
Fresh gas, boat gets used weekly almost year round. Ran fine yesterday morning. Took it out again yesterday afternoon, wouldn't get up on a plane.
Took it out again today to do some diagnosis. Same thing, no power, bogging when throttle is applied. Pulled the engine cover and while underway pulled spark plug wires to verify spark. Pulled #2, no change, Pulled #4, no change, Pulled #1 motor died, Pulled #3 motor died. Stopped and switched the port side ignition coils with the starbord side ignition coils. Same thing...no spark on 2 and 4, spark on 1 and 3. Ignition coils are good.
Pulled boat out of water and brought home.
Pulled sparkplugs out of 2 and 4, (grounded to cyl head bolt) cranked motor, no spark
Pulled sparkplugs out of 1 and 3, put them in 2 and 4 wires, no spark
(ie...still no spark on 2 and 4 cylinders)
Put sparkplugs from 2 and 4 into 1 and 3 wires, spark
Plugs are OK
Repeated above steps with plugs to double check results, now have spark on all cylinders. What?
Put plugs back in motor, fired it up. Pulled wires off plugs individually, all 4 sparking.
I have read that the usual culprit of one bank of cylinders not firing or firing intermitently is the coil/pulser/trigger assembly. And I have also read that trigger assemblies rarely go bad.
My questions to the forum people are....
Is there anything else on the motor that could be responsible for both cylinders, on one bank, losing spark at the same time and then getting spark back at the same time?
And
I've seen other post where it is suggested to test the "Switch box" (not sure what this refers to, or if this motor has one.
Also,
Can the trigger/pulser be bench tested or does it need to be on the motor?
Thank you, muchas gracias! for any help
Heres the beef....
Fresh gas, boat gets used weekly almost year round. Ran fine yesterday morning. Took it out again yesterday afternoon, wouldn't get up on a plane.
Took it out again today to do some diagnosis. Same thing, no power, bogging when throttle is applied. Pulled the engine cover and while underway pulled spark plug wires to verify spark. Pulled #2, no change, Pulled #4, no change, Pulled #1 motor died, Pulled #3 motor died. Stopped and switched the port side ignition coils with the starbord side ignition coils. Same thing...no spark on 2 and 4, spark on 1 and 3. Ignition coils are good.
Pulled boat out of water and brought home.
Pulled sparkplugs out of 2 and 4, (grounded to cyl head bolt) cranked motor, no spark
Pulled sparkplugs out of 1 and 3, put them in 2 and 4 wires, no spark
(ie...still no spark on 2 and 4 cylinders)
Put sparkplugs from 2 and 4 into 1 and 3 wires, spark
Plugs are OK
Repeated above steps with plugs to double check results, now have spark on all cylinders. What?
Put plugs back in motor, fired it up. Pulled wires off plugs individually, all 4 sparking.
I have read that the usual culprit of one bank of cylinders not firing or firing intermitently is the coil/pulser/trigger assembly. And I have also read that trigger assemblies rarely go bad.
My questions to the forum people are....
Is there anything else on the motor that could be responsible for both cylinders, on one bank, losing spark at the same time and then getting spark back at the same time?
And
I've seen other post where it is suggested to test the "Switch box" (not sure what this refers to, or if this motor has one.
Also,
Can the trigger/pulser be bench tested or does it need to be on the motor?
Thank you, muchas gracias! for any help