ignition problem 90Hp Mercury Sport Jet

[michaelwelborn]

Have a jet boat with the Mercury Sport Jet. When I got the boat was told it needs a new switch box. The old one had already been remove along with many other wires. My wiring diagram says that the blue wire and red wire from switch boxes goes to the stator. The stator has no blue or red wire. I read in a past forum that this engine had major problems with ignition and there was an upgrade for ignition. Got this boat form a friend who got it form another person so do not have any history on the engine maintenance. If ignition was upgraded is there another wiring diagram and why is there no read or blue wire coming form the stator?

 

[Barnacle_Bill]

Re: ignition problem 90Hp Mercury Sport Jet

What year is it?

 

[michaelwelborn]

Re: ignition problem 90Hp Mercury Sport Jet

1995 is the year model.

 

[Barnacle_Bill]

Re: ignition problem 90Hp Mercury Sport Jet

There should be a red & blue coming from the stator. Any signs of them being cut maybe? Don't know anything about an upgrade but that doesn't mean there isn't one. But even if there is it should still have the red and blue wires. Are you sure about the year? My manual doesn't show a 1995, 90HP Jet.

 

[michaelwelborn]

Re: ignition problem 90Hp Mercury Sport Jet

the boat is a 1995 mirage. should there be a serial number on the engine that would tell me the model or perhaps a model number?

 

[Barnacle_Bill]

Re: ignition problem 90Hp Mercury Sport Jet

Look for a serial number. It will start with a letter then 6 numbers. It may or may not have a 0 infront of the letter.

 

[michaelwelborn]

Re: ignition problem 90Hp Mercury Sport Jet

checked to see if the wires had been cut on the stator and they have not. I have 2 yellow wires 1 white and green and 1 green and white wire coming from the stator. The only # i saw on the engine that might be a serial # is 818153-05

 

[CharlieB]

Re: ignition problem 90Hp Mercury Sport Jet

Check page 70 of the CDI Troubleshooting Guide,

http://www.rapair.com/LinkClick.aspx?fileticket=OTMbPbGaMBs=&tabid=55&mid=384&language=en-US

Look under the heading 'Red Stator Kit' and you will find the wires that you have.

 

[michaelwelborn]

Re: ignition problem 90Hp Mercury Sport Jet

Thanks for all your help but I think I will junk it. This thing is a mess when it comes to the wiring.

 

[CharlieB]

Re: ignition problem 90Hp Mercury Sport Jet

If the compression is good then this can be repaired quite easily.

There really isn't that much in the way of wiring at all.

The trigger has two, three, or four wires (depending on # Cyl's) that connect to the switchbox, they are color coded and clearly marked on the switchbox.

The stator has a couple of color coded wires to the switchbox and two yellows to the rectifier.

The switchbox has traced colored green wires to the coils and a black w/yellow trace to the ignition switch that grounds when OFF to kill the ignition.

Ain't too tough now, is it?

 

[michaelwelborn]

Re: ignition problem 90Hp Mercury Sport Jet

I have found all the wires and have them hooked up but one. It is a red wire coming from the switch box. My diagram says it goes to the stator but my stator has no red wire. Also on the main wiring harness where it plugs together there are about four short wires that are not plugged to anything and my diagram does not even show them. Also when I went to connect my battery the starter engages without turing the ignition key.

 

[CharlieB]

Re: ignition problem 90Hp Mercury Sport Jet

Extra wires from the harness are no problem, that harness is made to be used on a number of models. I'll bet that you have a spare blue and a spare green, they are used for power trim that you don't have on a jet. Grey goes to a grey on the voltage rectifier and triggers the tach.

The extra red wire from the switchbox I'll have to look up, it doesn't ring any bells in my head, yet. It may have been for a special model tach, I need to do some homework.

The starter solenoid is triggered by the yellow wire with the lil red stripe on one of the smaller side terminals, the other one should be a black ground. The solenoid could also be stuck, disconnect the yellow wire red stripe then try to connect the battery, if the starter turns then replace the solenoid.

See, you CAN do this!

 

[michaelwelborn]

Re: ignition problem 90Hp Mercury Sport Jet

Thanks for the help. I did the test and it was the solenoid. I gave it a few tap and got it unstuck. I know that I will need to replace it. Thanks so much for the help.