I only used Ether a few times over the years and each time I gritted my teeth with all the banging and clanging it generates.
Agree with others, any time you can do without it, do it.
On batteries and starting, I had a JD 4230 100 pto hp, 400 cu in 6 cyl. diesel. It had a 6 volt battery on one side adjacent to the starter with one wire to the starter solenoid and the other wire (0) gauge looped around to the other side of the tractor where there was another 6 volt battery connected with the ground terminal under a bolt on the tractor frame.
Several problems:
Internal resistance of the batteries was in series and hence doubled the voltage drop during the 300A starting current
Cables were only 0 gauge which is more of a 100 A wire considering a 2% voltage drop at rated curent
Ground connection had to go from the right side of the tractor frame (and rusty connection) through the tractor frame to the rusty interface of the starter case to the tractor frame.
Considering you need 10V across the starter proper during the spinup, at 300 amps and a 12.7volt power source, you don't have any room left for connectivity resistance.
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It was not a winter starter and using ether on it a couple of times was more than I wanted.
I went to the OTR truck dealership nearby and bought a couple of 12v 925 CCA or thereabouts, case size 31 (⅜" centered studs) and had them make me up a set of 00 gauge cables that would run from one side of the tractor to the other.
Put one 12v in the right bracket, ran +/- through the new cables over to +/- of the left side battery and hooked them in parallel....right there I obtained a 4/1 advantage on battery internal resistance having it be low in the first place being new batteries and second being in parallel it was halved what it would be with just 1 battery and another 4/1 advantage....at least on the cable/connector resistances.
With about 1-1.5' 00 short cables made up, + cable went to the solenoid and the - cable was mounted to the chassis of the starter (nice and shined up) under a mounting bolt nice and tight.
The dealership had skids of those batteries and they were priced about 60% of what a similar tractor battery would cost me at a tractor store. I saved enough to cover the cost of the cables and fabrication expense.
Never again had a problem starting that tractor, winter or summer and never again, on my watch, did that tractor ever see ether again.