Want To Avoid Starter Rebuild On Cub

Guys (and Girls):

I've never been able to understand electrical systems. Here is the history and scenario.

1. 1960 Cub with six volt system . Left the push-pull switch 1/2 engaged and battery ran down. Put the charger on it (50 amps -6 volt setting). Forgot to disconnect the starter and charged for 10 minutes ; I then disconnected and went to other work . About two hours later ,the battery blew up.

2. Bought new battery and installed. Ammeter showed discharge only one time. Then went to neutral ,despite turning switch on-off several times.

3. Starter ,with new battery, never budged or responded. New battery puts out 7 volts and there is six volts at starter read from the starter lead .

4. Want to avoid expensive rebuild -- I am really cheap. I have new starter switch (device like solenoid on top of starter that engages with reach rod). Anyway to tell that replacing this will be a fix? Any way to avoid rebuild ?

Thanks

Well, 50 amps for an extended period of time will blow up any battery. I am kindly suggesting you need a friend to help you with this before you get hurt. Yes one can take a lead directly to the starter post to see if it will spin, but if the thing is in gear it may run over you. You really do need to know what can hurt you before you try certian tests.

I think it might be smart to find somebody to help you with this project. I have to agree with rbel. Mickey mousing and jerry rigging is not the way to fix equipment. I have learned the hard way that it is not worth messing with fixing stuff with duct tape and baling twine if the machine is going to be run every day to the day it blows up.

In the case of your starter, the starter is not bad, the starter switch contacts are burned and dirty. Your battery blew up because it was overcharged by your 50 amp non-automatic battery charger. The push-pull igniton switch does nothing to activate the starter, it just operates the ignition.

Another possibility is that the starter drive ("Bendix") gear has jammed against the flywheel ringgear.

Making SURE the ignition is "OFF", put the tractor in high gear and try vigorously rocking the tractor back and forth by yanking forward and back on the rear wheels. Keep out of it's way "just in case". If you get it to rock and turn the engine back and forth a bit (watch the fanblades) it will free up the starter. (IF it has jammed.)

I agree with the othrs bad accidents can and will happen. If your starter has a button on the top that has to be pushed to get it started remove the 2 screws and take it off the starter. Under it you will find a brass post on the starter and on the part you took off there is a piece of brass that moves when you press the button. Clean up both pieces and put back together and try it. On mine It had arched and caused burn spots so it could not make contact, but I did not put that much amperage thru it .

its been a while since I worked on a cub,first as I understand it you left switch on and ran down battery,might have burnt up points too.charging the battery will have no effect on starter,anytime!.but you did charge with a 50 amp charger,this is a no-no dont ever charge a battery at fifty amps,so called quick chargers have burnt up more batteries than any other thing,if you dont have time to wait for battery to charge, boost it only off high amp charger..as for point two,amp meter will not show a discharge unless points are closed with no other loads.your points are quite possibly burnt up from originally leaving switch on.. point three,if its positive ground you will see 6v at starter terminal(on starter)any time you check from block to post.point 4,wont help your problem one little bit,unless of course you were haveing a problem before this..want to know what your problem most likely is? clean your battery posts! dont matter if they LOOKED clean,new batteries have a film on the posts to keep them from corroding and even the slightest amount of corrosion will make them loose contact.every thing you say you have done ,besides burning up your battery, points to this.GUESS WHAT! when your amp guage went down and back up it lost contact with your battery post right then! one spark and you lost it,try it and see if it doesnt help!

Guys:

Thank you for your various suggestions and for your concerns for my safety .

I will try the practical ones and go to the rebuilder if none work.

Kajun

Want to avoid rebuilding a starter on a Cub?

1. Remove starter. Any leads that connect to the starter can then be extended and connected directly to the battery.

2. Make a plate to cover the hole where the starter originally mounted, in order to keep rain/snow/small children's hands out of the bellhousing.

3. Use the crank to start the tractor..

10 minutes on 50 amps is no biggie. If it was not boiling or gassingout, it was the battery that caused the explosion, (and possibly the discharge that you attributed to the switch) JimN

part of my job at the faa is diposing of toxic waste,mostly batteries,i see probably 100 a week,mostly with bulged cracked leaking cases.heres what happens to a battery when you charge it too quickly.when you charge a battery it creates heat,just like any other thing thats drawing amperage.except a battery is sealed or in the case of an old style battery very slightly vented.so you have to charge it slowly or it will get too hot,and begin to -a,boil in a wet cell battery or b,in the case of one the newer gel type batteries expand.when either of these things happen the plates inside of battery begin to slough off the coating made caused by the reaction between plates and acid.if it continues to get hot the plates themselves start to warp.just like a sheet of any metal will if you heat it.if they heat enough to warp enough the plates in them will touch each other and short out and sometimes explode right then.another thing that happens is that the crap that was sloghed off plates is held in suspension because when you take battery off charger it continues to boil.when this happens as it slowly cools down it begins to settle in bottom of battery case if theres enough to fill say the bttom 1/4 or so of plastic case,or whatever space is designed into battery for this purpose ,it will short across plates and it can explode later.try this the next time you need to charge a totally discharged battery,set charger on say 10 amps on this setting most battery chargers are regulated.watch the amp meter,if battery is truly way down ,when you turn it on it will start charging at say 2-3 amps and as battery heats/charges up it will climb to 10 amps.as battery becomes fully charged amp guage will again drop until charger hits its holding/maintaining charge of around 2 amps usually.BUT on a fifty amp charger,one that is unregulated ,you will bypass the regulator circuit.hit that battery with a full fifty amps all at once causing it to heat very quickly and continue to build heat the full time your charging.heat is what kills your battery,not the charging itself.this is why they have voltage regulators on our vehicles to protect the battery.the older the battery the slower you have to charge it,because the oxides/sulfates that build up on plates also make them retain heat longer.causing them to be more suceptable to damage.a brand new battery might handle 50 amps for ten minutes but im sure it will do it no good.most batteries have a charging rate written on the battery or it will be in the specs somewhere.hope this helps!

Fix the starter and keep the 50 amp charger off the tractor.Friend just fried a 43 buck coil with a 50 amp charger.Your tractor has a simple manual switch no solenoid.Starter brushes cost 3 bucks.You have just enough knowledge to be dangerous around electrical systems.