1955 cub drawing too much power on startup

[rolmstead3]

My cub has had a bad battery for the last few years and i have just be starting it by jumping it of a 12volt battery. today i got a new 6 volt for it, but now the 6 volt won't turn it over. i put a voltage tester on it and when i hit the starter it 0's out the tester, where might the problem be? it will still turn over with a 12 volt but not the 6 volt.

[Jim Becker]

Where are you measuring the voltage? directly on the battery terminals or elsewhere?

[ScottyD'sdad]

Start by cleaning the terminals on the starter cable, and the connection between the starter and the tractor. the 12V can probably break through a bad connection, better than 6 volts can.
Ed

[Matt Kirsch]

When cleaning terminals don't forget INSIDE the starter switch. That big lug can get burned by the arcing that occurs when you engage the starter.

[Jim Becker]

St. . . the 12V can probably break through a bad connection, better than 6 volts can.

Plus he has probably been jumping it with the jumper cable connected directly to the lug on the starter switch, not going through the battery cables.

[Eugene]

Couple other thoughts, corrosion inside the battery cables. Suggest replacing the battery ground cable and reattaching it to the top of the transmission/differential case.

Charge up the new 6 volt battery. Normally a new freshly store bought battery is only 80% charged, some times less.

Multi-meter, ohms setting, check the resistance of the negative cable from battery to terminal on top of starter.

[inairam]

I like this voltage drop test method to check battery and cables

viewtopic.php?t=38133

[Waif]

Be certain you have a very good ground. A bad ground does act like too much draw. Fought mine a while.
As mentioned elsewhere on this site,the braided ground cable can be an improvement.
Clean and tight surfaces on both ends!
Starter lug can be dressed with emery cloth. Good time to clean switch contact too.