Mercury 90HP 1989 or 1990?

[WildWillJAX]

My "SUPPOSEDLY" 1989 Merc 90HP 3 cylinder oil injected S/N OC 162559 (on the upper unit) has an ignition system that differs from ALL of the schematics that appear in the Clymer Mercury Outboard Shop Manual for 1972-1989 45HP through 225HP.<br />My ignition system has a single switch box mounted on the starboard side with 3 solenoids (starter circuit) mounted vertically just forward of the switch box and ignition coils. It also has an electronic control module mounted center above the air box housing just forward of the flywheel assembly. The Clymer book has nothing on this system. Can anyone explain?<br />Thanks

 

[phatmanmike]

Re: Mercury 90HP 1989 or 1990?

web page <br /><br />go here and save that page, i have exact same motor, just got it 2 days ago. where you at in fl?

 

[crashed]

Re: Mercury 90HP 1989 or 1990?

Sounds like you have the same setup as me on my 89 80hp.<br /><br />The system is a Thunderbolt V system, the additional module you refer to above the airbox sounds like someone has fitted the modified stator kit which comes with a seperate voltage regulator that sits on a plate mounted above the airbox, just in front of the flywheel.<br /><br />If this is the modified kit you can check quite easily by looking at two of the terminals on the bottom of the switch box. One should have a red wire, the other blue. Both these wires go to the stator, on the standard ignition system both of these wires are used. If you have the modified stator fitted then one of these terminals (blue?) is blanked off and not used.<br /><br />The ignition system is the same as the standard thnderbolt system, you just have a stator adaptor fitted (usually behind the starter motor or the oil tank) and the seperate voltage regulator.<br /><br />I could be miles off but I'm sure someone will put me right!