Wiring Problem on a 48 cub

Mon Feb 02, 2004 8:03 pm

I have A 48 cub that I am restoring. When I bought it, it was converted to 12 volt. I am putting it back to 6 volt. Here is my problem... I bought a generator (delco Remy #1101355 8M 6) with the regulator mounted to the top of it. The reg has 3 terminals. The wiring diagram that is on this site has a reg with 4 terminals. I think that I have a distributer and not a magnito. The face panel has a fuse, ammeter, ign switch and a lite switch that makes two moves, is this a 3 pole switch? Did I buy the wrong generator and reg? I've been messing with this on and off for two weeks and am starting to get fustrated. Can someone give me some insight on this mess? Serial # of my cub is 42927

Mike D :?

Mon Feb 02, 2004 10:07 pm

The generator you bought would be the right type for your cub. The unit on top is a cut-out, rather than being a regulator. It disconnects the battery from the generator when the tractor is stopped. The charging is controlled by the head light switch , which should be a 4 position switch, marked L, H, D, B (lo charge, hi charge, dim lights, bright lights). There was a wire that ran from the F terminal on the generator to the light switch to control the charge rate. The other terminal on the generator goes to the right terminal of the cutout, with a wire from the starter switch to the terminal on the back of the cutout ( assuming it is mounted with the 2 terminals facing away from the tractor, and the single terminal toward the tractor). The left terminal of the cutout is not used for most applications. The fuse would have been on the back of the light switch rather than in the dash. This diagram is for an H or M, but the wiring would be the same. http://albums.photo.epson.com/j/ViewPhoto?u=4001561&a=30065733&p=61732517&f=0

Mon Feb 02, 2004 10:35 pm

It sounds like your instrument panel is set up for a later tractor. Is your light switch centered or to the upper right of the panel?

Maybe you have a later tractor that has had the front casting (with serial plate) replaced with an earlier one. Have you checked your engine number or any casting date codes on the rest of the tractor? The TMtractors site has a good explanation of how to read the codes.

If you are trying to match your early generator and ??? wiring and later instrument panel with the wiring diagram (on ATIS Cub FAQ), you may have some sorting out to do.

Mon Feb 02, 2004 10:46 pm

John you just helped me out more than you could possibly know. Just today I took my old 6V gen w/cutout down to shop that specializes in generator repair to see if mine was ok. He said it was just fine after running it upon the varidrive. He suspected my problem was in my light sw. I'll be checking that tomorrow for why I've now lost all charge. However after looking at the print I noticed a wiring error thats been since I've owned the tractor. I rewired it shortly after I got it copying the same mistake with the new wires. Now I know why it would always boil over the old wet cell I had until I bought the gel cell. I've got a extra wire that connects between the gen. field and the cutout F connection. This will probably keep the gen in a full fielded condition. I've got the factory manual butt it doesn't show a diagram for a 4pos. sw and gen w/cutout. Well I'll be darned! This forums getting better all the time. Thanks again. Bill

Mon Feb 02, 2004 11:05 pm


Welcome to the board, always nice to have another Maritimer around. We are not that far away - about 1 1/2 hours. If you come up to Moncton at any time be sure to pop in and visit. Coffee, visit Ellie-Mae etc. She is a 6 volt system with the cut-out and I had to re-wire her, but she is working great now and can serve as a guide if need be.

If you don't have the correct switch, partsman has them, so give him an email. He is in Sussex and is real straight to deal with. Unfortunately, I only have the rear view pic of the switch,


and I can't find it by searching the posts either. TM Tractor doesn't have any available on their site.

Tue Feb 03, 2004 8:26 am

A wire from the generator F to the cut-out F would give low charge. If it and the light switch are both wired into the generator F, high charge of the light switch would still be the same. Low charge of the light switch would produce a charge rate between high and the normal low charge rate. Unless you use your tractor a LOT more than most of us, I wouldn't expect to to be a problem.

Tue Feb 03, 2004 12:17 pm

Jim- I keyed in on that wire because no prints show that connection being made. At one time couple of years ago I checked charge voltage at 7.5V. During times of prolonged usage the battery would be overgasing and electrolyte would run on the pan at my feet. I've heard others complain of the same thing. My fix at that time was a gel batt. Still glad I got the batt, its been good to me.

Tue Feb 03, 2004 1:04 pm

WK, as Jim said, having the F lead to the cutout should keep the generator on low charge, however if you had one also going to the light switch, the t resistors in paralel would give you a higher output than is the normal low charge setting. It wouldn't however give a higher charge rate than the switch would give in high charge postition. You might nedd to adjust the 3rd brudh on your generator a littl further away from the output brush to give you a little lower output. Also keep an eye on the gel cell battery. We use them in equipment at work, and they are subject to overheating if they get overcharged. After You run the tractor for an hour or two, feel the battery to see if it is getting hot.

Tue Feb 03, 2004 2:26 pm

John- Your on it man. I just went down to get this pic and was going to post a reply saying that I effectively have the field wired in parallel with the light sw resistor. Now depending on the cutout resistance I really could be over exciting this gen. most of the time. Anyway the light sw isn't controlling the output in this configuration. I copied this mistake several years ago without thinking anything about it. Just a couple days ago I questioned it and here we are now. Bill

Tue Feb 03, 2004 2:33 pm

Hey WK, I like the way you mounted your battery out of the way under the floor pan. Is that an Optima battery?.

Tue Feb 03, 2004 2:38 pm

Yes it is and that was the best batt purchase I ever made. About 7yrs and still going strong. They may be expensive for the initial purchase butt in the long run its dirt cheep. And you can't do that with a wet cell.

Tue Feb 03, 2004 2:45 pm

WKPoor wrote:Yes it is and that was the best batt purchase I ever made. About 7yrs and still going strong. They may be expensive for the initial purchase butt in the long run its dirt cheep. And you can't do that with a wet cell.

I thought it was but I could not read the label on yours. I bought an Optima for my truck about 7-years ago and I would not buy anything else as I have had great luck with its performance. I did not know that they made a 6-Volt Battery.

Tue Feb 03, 2004 4:44 pm

After re-reading both John and Jim's response I realized that I'm assuming the cutout sw has the least resistance, which may not be true. Either way the system was supposed to have the light control in control of the gen output I assume. If I'm correct then simply removing the one wire should restore normal charge operation. If your wondering about the wires, they are worth more than the tractor as I got that wire from work left over from Electrosonics aircraft installations. Works great on tractors!LOL :wink:

Tue Feb 03, 2004 6:38 pm

Maritimer, welcome to the board!! Good to have another Canuck with us, and a maritimer at that!! :D You will find any thing you need to know about cubs here!! These guys know them inside and out!!
I'll also extend an invitation to Cubfest Northeast at this time, it will be held here at my farm near Sussex NB, and co-hosted by Rudi. There will be more info forth coming ( as soon as Rudi and I can sit down together and fialize some details :lol: ).

Tue Feb 03, 2004 7:33 pm

Thank you Jim and John for your reply. Jim, my light switch is top right corner. Also, my face plate did not have the fuse holder in it, the hole was there so I thought it was missing so I tried to put one in. The ammeter also was not there, but there was a spot for it top left corner. It was plated over with a hole drilled in it and a red light the size of a quarter in the place. The ign switch was there and does work. It is smack dab in the center. Did they make a 48 without the fuse holder and ammeter? My light switch is different than the one you showed me Rudy, mine has no place for the fuse and the stuff on the bottom of the switch is not there on mine. But it is a cub light switch, It is a Delco Remy switch. The decals are all worn off.... of course.
Does this shed another light on things guy's? Parts Man, hello there.... Do you know where I can get the necessary things I need to change the cub to a Hi Crop?