787 cranks but no spark

[Slowmoe]

Ok I posted this in the boat forum, but since I got no responses and this page is much more active I decided to post here as well and I assume the ignition systems are similar.

I have a 1998 Speedster with twin 787 engines. The right side engine cranks and runs but the left motor is just turning over with no spark.

First I will swap the coil from he running engine and see if that is the culprit, then I will test/ charge the battery as well as trim back the plug wires, and check my grounds. Other than that, what checks can I perform to verify the other components of my electrical system are working?

Thanks in advance

 

[XP 787]

Not sure if this includes your Speedster but on some 787 skis the bracket for the trigger coil breaks. This is located behind the mag cover. P.S. if your trigger coil tests fine it can still be out of position because of a broken bracket. Check to see if your ignition coil is getting power. Also in your rear electrical box there is a single fuse, make sure its not blown.

 

[Slowmoe]

Thanks, I will check that. I think it is much more common for the 96 ski's than the later versions. Do you know which wire to test to check that the coil is getting juice? And I am looking for voltage, correct?


aLSO.....THE "BATTERY OFF" ROTARY KNOB INSIDE THE REAR DECK....dOES that completely disconnect the bttery from the electrical system so I can charge the battery without disconnecting the wires?

 

[racerxxx]

Thanks, I will check that. I think it is much more common for the 96 ski's than the later versions. Do you know which wire to test to check that the coil is getting juice? And I am looking for voltage, correct?


aLSO.....THE "BATTERY OFF" ROTARY KNOB INSIDE THE REAR DECK....dOES that completely disconnect the bttery from the electrical system so I can charge the battery without disconnecting the wires?

Ok, so I posted in your OTHER thread on your boat.

https://www.seadooforum.com/showthr...y-gets-fire-to-one-engine&p=581941#post581941


I get that you're hungry for info, but having 2 threads on the same topic so to speak is difficult for everyone to follow. So, would you mind if I merged the threads? I know, the boat side is slow, patience please and someone will answer. What many guys don't know is the boats are just glorified PWC's that seat 5+ people, LOL.

So, check that thread and I give you the specifics on what to check to see if you're coil is getting the signal to fire. Then, we can work our way backwards.

In the service manual there is a procedure on how to actually test the coil static with a DVM, takes about 5 minutes if that.


Now for your boat only question on the PWC side (some guys might not know boats have the disconnect)

The battery disconnect SHOULD disconnect the battery but.........I always disconnect the cables to charge the battery if needed. The terminals should only be wing nuts anyway. Just remember this boat MPEM is expensive......2 wing nuts are cheap and easy to disconnect.

 

[Slowmoe]

Thanks man. Feel free to merge them or whatever