Merc 900 90HP ignition wiring help

[falconair07]

I have an old Merc 900 90HP 6 cylinder 2 stroke motor that I am trying to wire up to see if it will even crank, and I don't know what to wire, where or how. I am mechanically inclined with an engineering degree, so I can catch on quick, but I've never wired ignition in a boat before or worked on an outboard mo. The SN is listed on the plate as 2940108, and doesn't bring up anything online. Any help to get this newbie on the water is much appreciated. Thanks!
-Steven

 

[falconair07]

Boat is a 1992 Spectrum 1600 fish and ski

 

[falconair07]

I’ve got the boat wired so that it turns over (starter engages) but I suspect that not having the kill switch wired is preventing spark. Suggestions on what to wire the black/yellow stripe kill switch wire to?

 

[merc850]

I can't find one under that Nr. Post some pictures of the block with the distributor and, cowling.

 

[falconair07]

[No message]

 

[merc850]

That's a point ignition ( 2 sets of points are under the cap); the red terminal cap must be removed first if you are checking the cap! It looks like you have a different control box than the original if all those wires in the 1st photo are from it.
Here's a diagram that should match the engine; the small black wire in the engine harness should power the ignition and you have to have "D" attached to the - battery terminal

 

[falconair07]

Thanks for the diagram. Yes the control box is from the 1992 spectrum 1600. Previously, it had a Force 70HP on it that was trashed. I'm thinking I need to connect the external wiring harness "B" orange, to the safety switch wire on the control box, which I think is black with a yellow stripe.

 

[merc850]

If you're starting this motor put the LU in a bucket with water that covers the prop. The safety switch is so you don't start in N; I would use a VOM to find 1: + power when the switch is in the on position, 2: + power when the switch is turned to start 3: push in the key and find the wire that will activate the choke. There is no "kill wire" for that motor it uses 12v to power the coils. Make sure the rectifier + is connected permanently to the + battery lead and the - cable is connected to the starter.

 

[falconair07]

[No message]

 

[merc850]

Oops "The safety switch is so you don't start in N" the safety switch keeps the motor from starting in gear like the one on your car.

 

[jimmbo]

One of the joys trying to figure out the horsepower and the year of a Mercury, strictly by a serial#