Can I start my outboard without a harness

jpl0069

Recruit
Joined
Jul 14, 2008
Messages
5
Hello,

I need a little help. I bought an old 1973 Merc. outboard model 800(80hp) w/thunderboldt ignition without the wire harness/controls(the six pin plug on outside of housing) and I was wondering:confused: if I will in anyway be able to see if this thing runs. Maybe a tip or trick I can do to start her up. Please let me know if you have some input. Thanks,
James
 

emckelvy

Commander
Joined
Jan 16, 2004
Messages
2,506
Re: Can I start my outboard without a harness

This recent thread addresses your question:

http://forums.iboats.com/showthread.php?t=262785

One thing I'd suggest is powering up the CDI box as discussed and "roping" the flywheel over with the spark plugs removed, reinserted in their boots, and laid on the block so the casings are firmly grounded.

The CDI will fire spark plugs even at "roping" speed so you'll have a good idea if it's going to work.

If the ign doesn't work, you'll want to troubleshoot before dumping a lot of $$$ in it.

Here's a good thread for that:

http://forums.iboats.com/showthread.php?t=209149

Cheers............ed
 

jarand82

Seaman Apprentice
Joined
Jul 10, 2008
Messages
37
Re: Can I start my outboard without a harness

all u need to do is hook up a 12v battery to the starter.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,119
Re: Can I start my outboard without a harness

James, a motor of that vintage may have a battery powered distributor CDI Ignition. If it has a distributor, you will likely need to put some power on the switchbox to get it to fire.

I recommend a wiring diagram for EXACTLY your motor, by serial number. Now check the ignition key function to see if it applies power to the ignition system or not.
 

jpl0069

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Joined
Jul 14, 2008
Messages
5
Re: Can I start my outboard without a harness

Hey guys, thanks for the quick replies:) I was able to fashion up a homemade harness per my wire diagrams. Now, I hooked up the red(power), black(ground), white(run position from key switch), and a momentary yellow(starter) to the outside motor connection. I hooked up all except for the yellow until I needed to start it. I have no spark or any voltage at my switch box ignition coil terminal but i do at the power in terminal. When should there be power be flowing through from + line in to the coil terminal? Is there a way I can bypass the switch box or does something else have to be connected to send power to the coil? All your help is appreciated!
 

Steven1962

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Joined
May 23, 2008
Messages
34
Re: Can I start my outboard without a harness

In my manuel I see a 1969- 72 800 with a type III IGN or a 1973-75 850 with a type IV IGN

what is the serial # for your motor so I can find what we are working on?

and are you sure it is a 800?
 

jpl0069

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Joined
Jul 14, 2008
Messages
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Re: Can I start my outboard without a harness

Yes, is it an 80 hp (800 model). Now I could be wrong about the age because thats what I was told. The serial number is 3191882. I do have a four terminal switchbox(green, brown, blue and red. I am not sure what model that is. I looked at your thread "emckelvy" from your previouse message and that test says "disconnect all 3 wires on the distributer side of switchbox" which I have four an no other wires on the opposite side??. Actually I am not sure of steps 2-6. I don't know what the"HV" is:confused:. Sorry for being a pain but this is getting frustrating. Thanks a million guys:)
 

jpl0069

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Joined
Jul 14, 2008
Messages
5
Re: Can I start my outboard without a harness

I think I found my switch box number which is 337-4411. Are there any tests for this?
 

Steven1962

Seaman Apprentice
Joined
May 23, 2008
Messages
34
Re: Can I start my outboard without a harness

Ok your motor is a 1972, you can not bypass the switch box. It takes 12 volt dc and transforms it to 120 AC to your coil.

How many wires are on your switch box and what colors? see if we can jumper and test it.
 

1976SRV190

Seaman
Joined
Jul 10, 2008
Messages
69
Re: Can I start my outboard without a harness

Hello,

I need a little help. I bought an old 1973 Merc. outboard model 800(80hp) w/thunderboldt ignition without the wire harness/controls(the six pin plug on outside of housing) and I was wondering:confused: if I will in anyway be able to see if this thing runs. Maybe a tip or trick I can do to start her up. Please let me know if you have some input. Thanks,
James

does it still have the battery cables on it? If so, I THINK you just have to hook up the battery and rope start it. It will be a tard to start on the rope if it hasn't been fired in a while. It may also need a switched set of wires in the harness pair to fire if there isn't power running to the switchbox.
 

jpl0069

Recruit
Joined
Jul 14, 2008
Messages
5
Re: Can I start my outboard without a harness

Hey guys, things were kind of funny here. Well, I found a schematic for my switch box and removed all the wires and after sweating in my humid 100 degree garage, frustrated after working on this for more than 4 hours last night, my last draw, She fired right up. I am not sure exactly what I did but it runs nice and smooth. I tell you guys what, this site is great though. All of you who helped me or given advice, my hat's off to you. We need more people in the world like you guys. Cheers

I'm an electrician and if anyone needs any info on residential or commercial electric, feel free to ask. Thanks again:D
 
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