Anyone know what merc engine this is? Need wiring help

[billwalsh119]

Hello, Im new to the forum. I was given a boat and would like to fix it up. It has a Merc. 90 straight 6? (new to outboards but not to engines) Ive tried searching the serial number but no luck. Serial stamp says 7162982.

My problem is the wiring is a rats nest! I cannot make heads or tails of what im looking at.

The boat was running when put away. so im guessing all the wiring in the ignition switch is fine. but at the back there are tons of loose wires. It came with no battery so everything was disconnected. Can anyone tell me where to find a wiring diagram to get it hooked up correct again? Is this a custom wire job or are the colors correct?

Looking forward to firing this thing up!

Thanks in advance for any help.

ps. Ive searched for hours on wiring but could not find anything that looked similar to my parts.

 

[billwalsh119]

Re: Anyone know what merc engine this is? Need wiring help

more pictures

 

[billwalsh119]

Re: Anyone know what merc engine this is? Need wiring help

few more

 

[calvinator]

Re: Anyone know what merc engine this is? Need wiring help

visit maxrules.com A lot of info there!

Serial # indicates Mid 80's 90HP, 6cyl.

Wiring diagram:
http://www.maxrules.com/oldmercs/Wiring/1966ona/37.jpg

From the pics, it looks like you have power trim. All those wires in the back -- two will be for engine to battery... Then you should a thick wire loom that goes from your control box to the motor via a plug style connector (indicated in the wiring diagram). I see the wiring harness is there on the starboard side of the motor. That doesn't look hacked into.

Some of those other wires related to the power.....two for power tilt to battery. Then some more of those wires will be for the tilt switch. Often the tilt switch wires run back to the control box, but from the pics of your control box I don't see a switch. Maybe the PO has the tilt switch located by the motor.

Lastly, get a Mercury Service Manual for that motor. Everything is explained. Straightforward to work on if you are the handy type or want to learn.

 

[carholme]

Re: Anyone know what merc engine this is? Need wiring help

Bill;

That is a Canadian built engine and the s/n comes up as:

90 1981 ELPT 5594657 - 5996390 7147088 (7147088 is the starting s/n of that year)

From here:

MERCURY OUTBOARD MODEL YEAR GUIDE 60 HP - 100 HP -- Mastertech Marine

Parts Listing:

MERC 90 - Mercury, Mercruiser, Force, etc. Parts Lookup

The service manual you require is P/N 90-86134--4.

Gerry

 

[billwalsh119]

Re: Anyone know what merc engine this is? Need wiring help

Thanks for the fast replies guys!

I got the motor cranking today. Should have it back to life by the weekend. Cant wait