49 cub mechanical restoration electrical help

[bwagner17]

first time posting to this forum after years of using it to find help on my old cub.

resently It blew the head gasket and I decided it needed a lot of other work while I was doing it. I sheared a head bolt off in the process and spent some time fixing that mistake, had to bore out the radiator drain because the square plug was now a circle . new head gasket, new belts, new spark plugs and wires, new fluids for steering box and tranny and final drive, new gasket for final drive pan, I removed them and cleaned them out and fresh fluids. new upper water hose gasket, carb was rebuilt, new oil pan gasket, new oil, and with some luck it should be useable in no time

a lot of the original wires are rotten and im replacing them but not all of the stuff worked before anyway. can anyone get a wiring diagram for a tractor with magneto and the original 4 position switch?(im getting a new one from ebay unless someone says NO!!!).

my generator is shorting out internally and im wondering if I should get a kit to rebuild it or just replace it, (so I don't mess it up "fixing" it). or should I just skip the generator all together and get an alternator and then a simple 3 position switch?

how do I know if my magneto is working? the engine ran before but it could just be draining the battery slowly because I always put it back on a charger. as im reading it seems that my setup is the most complicated one that is possibly made from IH .

Lets say I stick with the generator and get a new one and use the original switch config, my preference if it works best and is most reliable, do I need to get some type of regulator on top of the generator? its got what appears to be a cut off switch in it just a simple one coil deal but the rust and lack of paint on the top of the generator indicates that there usto be a larger regulator on top. will going back to stock not work without the proper regulator?

I know its a lot of questions but im so lost when it comes to this wiring stuff. give me a briggs

[bythepond88]

First - welcome to the greatest forum on the web!

If you truly have a magneto, it has nothing to do with the charging problem. It is self contained, and generates spark internally and has no connection to the electrical system. The only wire for a magneto system (other than the coil and plug wires) is to ground the magneto to shut the tractor down. You can tell a true magneto system, because the coil is square and attached directly to the unit.

As for rebuilding the generator yourself, I would be inclined to try that only if I knew exactly what was wrong. I'm not too good at troubleshooting so "shorted internally" doesn't help me help you. Fortunately, there are electrical wizards on board who will be by shortly to help with that.

I wouldn't agree that the magneto/generator system is the most complicated, rather the contrary. At least your ignition is separate from the rest of the electrical, and there is not that much electrical on a cub to begin with. Here's a troubleshooting chart that you should start with to make sure the generator is indeed the problem. Before doing anything else, make sure all connections, especially grounds, are clean and bright. Many times that is the source of the problem.



From your description, (four position switch and unpainted area on generator) it sounds like your tractor originally came with just a cut-out. If your cut-out is shot, and the generator has problems, it would probably be more cost effective to simply convert to a 12v system. However, the cut-out may just need the contacts cleaned and/or ajusted.

Don't worry about asking questions, we love to help.

Also we want pictures. Not only do we like to see each other's tractors, in this case it will help us figure out what your set up is and help you better.

[bwagner17]

Ok thanks for the help I'm sure I've got the magneto system it is just like you described. but I'm more interested at this point on weather to put a alternator on the tractor and a 3 position switch. I don't want to convert to 12v due to my lights are all 6v and brand new. Looking at yesteryear website I see the alternators charge better and are less than half the price of a new or reman generator. Can I get a 6v alternator with off,low beam, high beam switch? Do I need new pully? Or ammeter since the alternator pushes so much more power? New bracket to mount it? If it is cheaper and works better I think that is the way I would like to go.

[bythepond88]

I'm all for keeping original as much as possible. I don't know whether there is a 6v alternator that is any less expensive than a 6v generator; someone else here may. Before you got throwing parts at it, though, clean all connections as I suggested, then go through the flow chart and see where the problem(s) is/are. How bad does the cutout look (you mentioned rust)? If it doesn't look too bad, pull the cover off, clean the contact surfaces, and check that the air gap is correct. I have resurrected two regulators by adjusting the air gaps.

Here is a link to a page with wiring diagrams: http://s101.photobucket.com/user/farmallbob/library/Farmall%20Tractor%20Wiring%20Diagrams/#/user/farmallbob/library/Farmall%20Tractor%20Wiring%20Diagrams?sort=4&page=1&_suid=1400794794512008746101226917024

[bwagner17]

I am sure the generator is fried I have pulled the back of it off and inspected that the brushes were indeed touching and it appeared to be in good shape however when power is applied to the terminals the motor does not spin and the wires will spark when touching the battery which tells me there is a short because the motor should spin. as far as originality this is not a show tractor by any means I merely want it to run reliable and be able to do work for me. do you know if yesteryear is a good parts supplier? I live down the street from a case IH store and can get stuff there if they are the best option.

all wireing is being replaced and still I've got this problem.the cut off is in exelent shape inside of its housing I bench tested it and it works fine.

as far as the expenses I don't know if I put it in a previous coment but I have found alternators to be roughly $110 for 6 volt systems and generator rebuilds to be around $300 and both switch configurations are about $60.

[bythepond88]

I don't have any experience with Yesteryear. If you are going to order on-line, you can't do any better than TM Tractor. Their service alone makes them the best choice, but they are also a site sponsor. There is a link at the bottom of the page.

$300 sounds way steep for a rebuild. Have you checked with JP Salvage (also a site sponsor with a link at the bottom of the page and great service) for a used generator and switch? He can probably set you up.

[Eugene]

I'm suggesting the 12 volt single wire alternator conversion.

I don't want to convert to 12v due to my lights are all 6v and brand new.

12 volt bulbs are not that expensive.

I took the lights off my Cub because I never use the tractor at night. So, why bother having working lights.

Do I need new pulley?

If the belt sizes are different, put the pulley from the generator on the alternator.

Ammeter since the alternator pushes so much more power? New bracket to mount it?

You will need a new amp meter. But the mounting bracket should come with the new amp meter.

The other change you need going from 6 volts to 12 volts is at the ignition coil. You will need a ballast resistor or purchase a 12 volt coil with internal resistor.

Just my opinion, for a working tractor the conversion to single wire 12 volt alternator is the way to go. Sunday, I can pick up a single wire 12 volt alternator at any open auto parts store. Where are you going to get a 6 volt alternator?

[bwagner17]

I have the mag distributer so it is neer impossible to find a 12v coil for that system. It is a special
Square part. And I need lights to work. I just bought 6v bulbs as in I haven't even used them yet. I don't think after I get an alternator installed it will fail with the limited use I use it for. Ive talked to the local IH store and they didn't have a 6v alternator but recommended yesteryear and it should be about $100 cheaper than a reman. I'm currently looking into a rebuild. Will see how much that costs.

[Eugene]

I have the mag distributer so it is neer impossible to find a 12v coil for that system. It is a special Square part.

Brain was not in gear. You will not need a coil for a battery powered ignition system since the magneto works.

[bwagner17]

Still how often does a alternator fail? I know they are hard to find but that doesn't matter if the one I got never fails

[Eugene]

Still how often does a alternator fail? I know they are hard to find but that doesn't matter if the one I got never fails

I have repaired or replaced an unknown sizable number of alternators over the years. Alternators are very reliable. But they also fail, fail often enough for the auto parts stores to stock a good selection. If alternators didn't fail there would be no reason for auto parts store to stock them.

Just pointing out that the proposed $100- 6 volt alternator can be replaced with a readily available 12 volt single wire alternator at half that price.

[bwagner17]

Good point but with lights and switch it evens out

[bwagner17]

And $100 battery

[bwagner17]

I have read in another forum about this that a delco remy 10si can fit under the hood and a 6v kit can be bought for it all for about $110. however this kit is a positive ground kit. I would be interested in doing this conversion to positive ground as it seems to be the better option as far as jumping my other equipment and such anyway. is this conversion to positive ground imposible to do with the magneto coil system? the wires on the coil need to be reserved I know but I don't know how to do this on a magneto coil. does this sound like a good idea? so far my total cost analysis for 6V alternator is battery free, alternator $110, switch $60, coil switching? $? cost for 6V generator is battery free, coil free, generator rebuid/ reman ~$200, switch $70, and possibly cut off, regulator? $? and 12V system would be battery $100, alternator $70, switch $60, coil? $?, lights $50. total costs are 6V alternator : $170, 6V Generator : $270, 12V alternator : $280 +- coil problem. clearly 12V is not sensible and the 6V alternator is the best option.

[bwagner17]

I have read in another forum about this that a delco remy 10si can fit under the hood and a 6v kit can be bought for it all for about $110. however this kit is a positive ground kit. I would be interested in doing this conversion to positive ground as it seems to be the better option as far as jumping my other equipment and such anyway. is this conversion to positive ground imposible to do with the magneto coil system? the wires on the coil need to be reserved I know but I don't know how to do this on a magneto coil. does this sound like a good idea? so far my total cost analysis for 6V alternator is battery free, alternator $110, switch $60, coil switching? $? cost for 6V generator is battery free, coil free, generator rebuid/ reman ~$200, switch $70, and possibly cut off, regulator? $? and 12V system would be battery $100, alternator $70, switch $60, coil? $?, lights $50. total costs are 6V alternator : $170, 6V Generator : $270, 12V alternator : $280 +- coil problem. clearly 12V is not sensible and the 6V alternator is the best option.