70s 850 control box upgrade

[brownksee]

Hello!!

I bought a 71 silverline tri hull with an 85 on the back. Needs a new control box put in it before I can take it out on the water. The mercontrol that came with it, the wiring was shot in the inside and the key was missing.

I was wondering if they are upgradable? instead of buying another used on off ebay, can a guy buy a new single handled control box that will plug right into the 85?

Someone can make this real easy for me and post a link to one that will hook right up!!!

Thanks for the help in advance!!!

 

[Chris1956]

Re: 70s 850 control box upgrade

Aftermarket controls are widely available for Mercs. Most any Merc control box will work. The tricky part will be the ignition wiring. If that 850 has a distributor, you need to put battery power on the ignition (white) wire, for it to run. Newer motors with ADI ignition, unground the ignition wire to allow the motor to run. Your original Merc wiring harness worked with both types of ignition systems.

 

[brownksee]

Re: 70s 850 control box upgrade

Thanks for the quick reply Chris!

I have the original wire harness that plugs into the side of the motor. So if I buy an aftermarket one, I'll have to rewire it to work with the old distributor ignition?


http://www.iboats.com/881170A_3_for....243446--**********.098044815--view_id.117285

Found this one... So all Ill have to do is splice my old plug into this one?

And what about the cable controls? Do you think the stock cables will connect right into this box??

Thanks again!! This site is the greatest!!

 

[brownksee]

Re: 70s 850 control box upgrade

anyone else have ideas???

 

[Chris1956]

Re: 70s 850 control box upgrade

That control should work. You will need to splice your white ignition wire to that control's accessory wire. It is likely colored purple, if they follow the OEMs color coding. The cables should also work.

You will need to splice the choke solenoid(grey), but I forget the new color. Your brown wire is the tach, which get spliced to the grey tach wire, the starter solenoid wires are both yellow, balck is ground in both harnesses, you can skip black/yellow, since that is the killer wire for ADI ignition (orange for your harness).