Mid 60's electrical system - Current drain

[steve86]

Hi, I am starting to work on a 1965 Sears fiberglass boat with Elgin (McCulloch) 45 HP motor. The motor appears to be in good condition, knock on transom wood, and with the cover off the only apparent work I can see was on the fuel pump (slightly mangled bolt heads).

Four years ago I see the last owner of this boat asked a question on this forum about procuring a throttle cable and to judge by the current status, he did find it!

After spending a week stripping and repainting the trailer I am finally starting work on the boat. Have already installed the Pretech rotary steering upgrade purchased here on iboats. Slick.

The ignition switch was obviously sticky and dirty inside so I replaced it before proceeding. Now I can turn the key to crank for a moment, and yes, I do get a brief crank before letting off. The "choke" button is separate and I hear what sounds like the fuel pump when pressing the button (seems normal to me).

Now to my question: On putting the key back to "on" (motor isn't running -- I just wanted to test if the starter activation would work), I smelled a hot or burning smell. It was obviously coming from the vicinity of the ignition switch and seems to be from a large ceramic component adjacent to the switch. I measured the current and it is almost 7 amps. This is with no lights or anything on. Man, that would run the battery down quickly if you left the key in the on position, not to mention catch the boat on fire possibly! Obviously the big ceramic component is there for a reason. I guess it is a resistor and certainly does dissipate the heat.

Is this normal? What happens then when the motor is running?

Also, assuming all the above is OK, what is the proper way to use the "choke" button? Just a brief "buzz" before cranking the motor? And a couple primer bulb pumps before that?

THANKS

 

[steve86]

Re: Mid 60's electrical system - Current drain

Maybe I've found the answer in manual I got on eBay.

It says "The ignition system incorporates an ignition switch and a ballast (resistor) unit which is mounted on the powerhead. The ballast is designed to prevent burning of the points if the ignition switch is left on with motor not running and points closed"

Sounds like what I'm seeing, doesn't it? The only difference is that the ballast is next to the ignition switch on my boat. Those were the days -- contact points. Makes me feel like finding some spare points.

P.s. I guess on this type of ignition system you just don't leave the key set to on without the motor running. Didn't know that before.

 

[Chris1956]

Re: Mid 60's electrical system - Current drain

Steve, The only way you will have a ballast resistor is if you have a battery driven ignition, most likely with a distributor. Most outboards of that vintage (Merc and OMC) had magneto ignition(a magnet, a coil a condenser and a set of points per cylinder). No battery power was required to create the spark. To stop the motor, the points were grounded. In addition the fuel pumps were mechanical, not electric.

I do not know anything about your outboard, but recommend you check out what kind of ignition you have.

 

[jtexas]

Re: Mid 60's electrical system - Current drain

with respect to the choke (I don't know that motor specifically, but in general), that switch most likely activates a solenoid that closes the carburetor choke plate(s). If you'll take off whatever is in front of the carb(s), you should be able to see what's going on there.

BTW, there were a few years in there when battery-driven capacitor discharge ignitions were used. outboardignition.com has info on OMC merc force chrysler - no mcculloch though. good luck

 

[steve86]

Re: Mid 60's electrical system - Current drain

Chris, thanks for the background info. Yes, the same manual confirms that my motor has battery ignition with distributor. Just a couple of years before mine the 45s had magneto ignition. I noticed from another thread that a clue my motor has battery ignition is that the ignition switch doesn't have the ground-magneto connection. I did find a spare set of points, BTW.

Jtexas, I guess you also must be right about the choke plate. Whatever it is it works. I see that the fuel pump is mechanical now.

The motor appears to have two single barrel Walbro carbs; this I found by matching up photos from the manual. Various years had Walbro, Carter, Tillotson, or Marvel- Schebler.

This is all very interesting to me; I have always been a two-stroke motorcyle guy but no outboards except my dad's 7.5 McCulloch when I was a kid. We still call them two smokes.

I got a new steering wheel off eBay from a fancy ocean-racer type boat. Pretty funny on my old Sears.