4020 voltage, 1971 diesel

ARAYT · Jan 13, 2023

Can someone tell me if the 4020 ever came wired as a 6 volt system? I have a friend that is trying to get his up and running and he thinks it was wired as a 6 volt system. It has 2 each 6 volts batteries but he thinks they are/ were wired parallel. He said the neg is connected to frame and from there not sure. Appreciate the help.
Thanks Ray

zzvyb6 · Jan 13, 2023

Yes, the 4020 came with 2 6V batteries wired in series. Everybody I know replaces them with 2 12V batteries wired in parallel. Plus we used to occasionally throw 24V at it to start using a battery cable double knife switch to cross over the main hot wire. It's not as bad as it sounds because the cables attenuate the power supplied. Fast start, eh ?

Tx Jim · Jan 14, 2023

Ditto '69-'72 4020 came from factory with 2 six volt batteries wired in series for 12 volts. JD decided on 55 series rowcrop tractors that two 12 volts batteries wired in parallel is better than two 6 volt in series & I agree.

I've owned a JD 4255 since Feb. '93. WOW that will be 30 yrs in a couple of weeks.

Tell your friend to check relay mounted on firewall above starter utilized to send extra amps to starter solenoid start terminal to be sure it's receiving a ""good ground connection""".

ARAYT · Jan 14, 2023

Thanks for the reply zzvyb6. I'm aware of the 6v batteries but did any come wired in parallel, a true 6 volt system?
Thanks Ray

ARAYT · Jan 14, 2023

Thanks TX Tim, Will check the ground. I guess we were typing at the same time, please disregard the previous question unless there's more info. Thanks Again!
Ray