More wiring questions - 1977 Cub

[Crimson Tim]

Hi,
While you have the hood off the Cub, I would oil the governor linkage and where the piece pivots that holds the governor spring. It is on a shaft that goes all the way through it.
They commonly get tight there from no oil. Try to work oil into both ends of the part, and get oil through the shaft. The shaft is solid on the governor.
Here is a pic, oil where the cotter key is, and the other end of the part.

Thanks, Glen. Yes, they certainly do get tight there. That was the first thing I did with this Cub, because the governor was non responsive. It didn't take much to free it up nicely, and all is good with the governor now.

I need to oil the fan, though. I haven't done that yet. And check valve adjustment.

if interested I have bought the main wiring harness on ebay from porch electric, complete with connectors just plug it all in, it was $80 with shipping, just like the factory harness

That's good to know, Tim. That's at least 25% if not 50% lower price than the other plug 'n' play wiring harnesses I've been looking at. Do you have a link? Or what search term do you use to find them the fastest?

[Bob McCarty]

porchelectric.com

[Crimson Tim]

Oh, you were so close. The resistor was originally fed through the ignition switch so switch off there was no drain. After the alternator is charging, whatever voltage it produces shows up at the exciter lug. The resistor keeps that voltage from backfeeding enough current to run the ignition when you shut the ignition switch off.

By the way, the ammeter resistance should be very low, so low most ohmmeters will show 0. I don't remember the ballast resistor resistance, I think in the 10 or 20 range.

And the whole point of the switch, since it is not present in the original wiring, is that the 10si alternator will self-excite at the slow engine speed of a Cub, but most alternators don't excite until reaching an engine speed higher than a Cub will ever go? Therefore a non-10si needs this little boost via the switch to get it working?

[Crimson Tim]

I got out the inspection camera to poke around the alternator. I did find the ID info right where you said it would be. However, the metal is so badly pitted, I can't think of any way to make it legible. Oblique lighting, taking a rubbing.... I don't think there's enough texture left to get at any numbers out of it.
The auto parts guy was able to get enough information out of the rebuild sticker to feed into the test machine, so maybe I'll take those numbers back to them again and see if they can tell me what this is.

[Glen]

Hi,
Try putting a little motor oil on a rag, and rubbing the aluminum some with a rag where the numbers are, that usually removes some corrosion, and polishes it some. You might be able to read the numbers then.

[Jim Becker]

. . . the pretzel tied spark plug wires. . . .

I thought maybe the knots were home-made RF chokes!?