Puzzeling Question

Sat Jul 10, 2004 5:50 pm

I've been using my newly restored 1955 Farmall Cub and it will not start after using for more than an hour. It is strang because the battery goes dead to the point the amp meter is not showing anything it is like there is no battery hooked up. It was a brand new battery, 2 months old. So what I did I took a battery out of the 56 cub and put it in the 55 and it started right off and ran fine. I tried the battery in the 56 that I took out of the 55 and same result, Nothing. The kicker of the deal is, The 55 ruined the new battery that I put in it out of the 56. So it has ruined 2 batterys in a day. Is there some thing hooked up backwards. Or is it bad luck with getting bad batteries. I tried to charge them also but that didn't help a bit the charger wouldn't even show and charge on the needle. I don't know what the deal is but It happened when I bought the new battery and I thought it was a bad cell or the old battery was on good anymore since it was over 2 years old. This tractor plowed snow all winter without one problem like this and one time I was out for 5 hours straight and never noticed anything like this to.

Also I smell a real sweat sent like something is getting hot. I kinda figured it was my voltage regulator or generator burning. I could really notice the smell this morning because I had to get off and take a break it was so bad. Also I am lean towards some bad wiring since it is all chopped and spliced in sveral places too.

If anybody has any hints that would be great because now I have to junk batteries and they aren't cheap to replace and I don't want to buy more than two because every machine will have a new battery after this weekend now.


Sat Jul 10, 2004 7:42 pm

Witth the quick death of the battery, and that smell, I would be looking for shorts. Use an ohmmeter, and see if any connections are grounding where they shouldn't be. Also check the VR to see it is working properly. I remember that smell from one time while fishing, the metal fish basket was touching both sides of the battery. That thing was red hot!

Sat Jul 10, 2004 7:49 pm


After an hour of driving the Cub, perhaps the battery is fully charged and the voltage regulator has temporarily cut out the generator. It doesn't take a lot of amps to keep the battery charged once it is up to full charge after being drained down somewhat from start-up. Therefore, the amp meter will drop to around "0."

When you say that the tractor will not start up after running an hour, will the starter turn over or is it dead? If the starter turns over, but still won't start, it probably has a vapor lock from the heat of the engine boiling the fuel in the fuel line and carb. I have that happen on occasions when the weather is really hot. The fuel mixture is so lean that the tractor won't start. If I let it cool off a little, the fuel mixture is rich enough to start again.

As for the sweet smell, perhaps you overfilled your radiator, and it is venting off some of the excess coolant. The radiator fluid level normally stabilizes about 1 - 1 1/2 inches below the filler neck. See if you are losing coolant out of your overflow.

Hope some of this helps. I am by no stretch a Cub expert, so maybe others will give other suggestions. Good Luck.

Sat Jul 10, 2004 8:38 pm

Sounds like the voltage regulater is stuck making the gen. charge to its max, frying the batt. the smell would be very strong like boiling vinegar


Sat Jul 10, 2004 9:57 pm

Does the ammeter show a discharge if the lights are turned on and then a high charge when the tractor is started? If so CCB is probably right about the regulater being stuck. If it shows discharge or charge with the lights on or tractor started (needle swings the same way under both conditions), you need to check the polarity of your battery (if 6 volts should be + post to ground) and then polarize your generator.

Sat Jul 10, 2004 10:34 pm

I have been thinking the voltage regulator because I think it is about 20 years old and maybe the wiring because it is shot and fried in places. I thought at one time the sweet smell was my generator overheating but am thinking more towards the wiring or voltage reg. I jumped it with a good 6-volt battery and she started right up quick with the bad battery in it. The meter showed strong positive chargeand strong neg charge w/ the lights on. It can be a few things that I will investigate some time in the next few weeks. Thanks for all help