Spark is Back But Engine Won't Turn Over- 90 HP SportJet

[cowansauto]

Thanks for the suggestions and words of encouragements from the NO SPARK thread http://forums.iboats.com/showthread.php?t=577914 NO SPARK thread. I replaced the switchbox with a used working CDI unit and I have spark on all three cylinders. Spark is present with yellow/black wire disconnected at rev limiter and at switchbox. When I put the engine back together I mistaklingly adjusted the trigger arm some which might be some of the problem.

I have a primer bulb installed inline and the gas valve is on so I believe it's getting fuel to the filter.

Here is what I wonderd could be the issue:

• Timing off at cranking speed. Never checked this when engine was reassembled. I'm not too clear on the proper way to do this without the spark tester tool that the Mercury manual recommends.

By disconnectinght yellow/black wire at the switchbox and still seeing fire, this eliminates the possibility of the kill switch being bad right?

 

[jerryjerry05]

Re: Spark is Back But Engine Won't Turn Over- 90 HP SportJet



If you have spark,fuel and compression.
How much did you adjust the linkage?
Just a turn or 2 won't make it not start.
It would start but not run great.
You sure that the pack was installed right?

The wire thingy is what i use to make sure i don't blow the pack.
The static timing is what you need to do.

If it SHOULD start,but won't?? Try a shot of starting fluid?

 

[pnwboat]

Re: Spark is Back But Engine Won't Turn Over- 90 HP SportJet

Disconnecting the Black/Yellow wire at the switchbox simply eliminates the Kill circuit that the lanyard is normally connected to. Sometimes instead of a lanyard, there is a switch on the Throttle control that is labeled "Run" and "Off".

If you have spark with the Black/Yellow wire disconnected, but lose the spark when you connect it, that means that you have a problem with the Kill circuit.

1. Either the ignition key is in the OFF position, or it's bad or not wired correctly. If you have a switch on the Throttle control, it's in the OFF position.

2. The Kill Switch is bad. You can check it with an OHM meter. With the lanyard attached, it should read OPEN. With the lanyard disconnected, you should read a short. It kills the signal to the switchbox by shorting it to ground.

3.You have a short to ground in the Black/Yellow wire.

4.Possibly a bad Rev Limiter. I'm pretty sure you can by-pass the Rev Limiter.

This Kill circuit is used to stop the spark to the motor when you tun the key to the OFF position. If the motor starts with the Black/Yellow wire disconnected, you cannot turn the motor off with the key. You can either engage the choke long enough to stall the motor, or put your hand over the carbs to block the air, our as a last resort, start pulling the spark plug wires off of the plugs.