Jim in LA

Well-known Member
I bought a new battery to replace the 3 yr. old one on my '49 8N 6 volt system. It's a continental same as the previous one. The engine has become slow to turn over and it will stopp turning and while still holding down the starter button it will finally spin over and start running. I took the battery out yesterday and put it on conventional charger all afternoon. The meter went from 7 0r 8 amps down to 5 amps over about five hours. The store charged the battery(which they had to order from the warehouse) prior to me picking it up and I put it on a trickle chsrger for a couple hours before installing and I was disappointed in the performance immediately. All grounds and connections check OK, I can't detect any excessive current draw, no overheating cables or wires. I'm taking the battery back to the parts store and have them put it on their load tester, If OK then I will look at starter, which to my knowledge has never been serviced since 1966 when It was totally rebuilt.
 
Voltage drop test. With voltmeter leads on the battery posts, what does it read at rest, with everything off? Next what does it read when the starter is cranking the engine over?
 
Google voltage drop test, not the type with the leads on the battery. It will show you how to check how much drop you have in each section of the circuit. Sounds like you are losing it somewhere, possibly the solenoid.
 
Took the battery and had it tested, got back home and hooked it up and checked ground cable I replaced last week and noticed no washer under the bolt head on the dash frame. After installing a washer and tightening cables good, the tractor fired right up. I had installed the flat braided ground cable and removed it due to decay and replaced it with a 8 gauge cable and did not get it tightened up properly. The other six volt battery would not hold a charge and it was three years old. Complacency will getcha every time.
 
Took the battery and had it tested, got back home and hooked it up and checked ground cable I replaced last week and noticed no washer under the bolt head on the dash frame. After installing a washer and tightening cables good, the tractor fired right up. I had installed the flat braided ground cable and removed it due to decay and replaced it with a 8 gauge cable and did not get it tightened up properly. The other six volt battery would not hold a charge and it was three years old. Complacency will getcha every time.
8 gauge is no where near heavy enough for a 6 volt system. You need 0 or 00 as the battery cables
 
Is the dash frame more than sheet metal where you attached? If you have ground to sheet metal you should move the ground to a heavy chassis point, under a starter mount bolt is best. And I will agree with old that you should use at least 0-gauge cables for best long-term service.
 
Is the dash frame more than sheet metal where you attached? If you have ground to sheet metal you should move the ground to a heavy chassis point, under a starter mount bolt is best. And I will agree with old that you should use at least 0-gauge cables for best long-term service.
Oh no the sky will fall because you agreed with me LOL
 
I had this problem on my 2N (also 6v), and it went away when I replaced the Bendix on the starter. I'm blown away how fast it turns over now.
 
So im a 6vt guy, / advocate. People tend to talk down 6vt alot. The newest car tractor ect that came with 6vt was new over 60 years ago. No one remembers what a 6v system is like when it was new. I believe 6vt system maintenance should be carried out every other year like any other scheduled Maintenance. Every other year i take an hour to disconnect every wire. clean every wire tighten every nut and i use a conductive Coper Kote anti seize on them to prevent against corrosion and give a better conductive connection.

Starters Eventually need love to. if you haven't inspected it pull the brush cover. Look in spray out with electrical connector cleaner to get rid of all the carbon and check brushes and commuter ware. If your commuter looks scored up. Pull it, you can chuck it in the drill press and use a fine mill file to clean it up and polish it with some emery paper. (dont forget to score cutback the insulator paper with a carbide scribe so the isolators sit about .005-.010 below the commutator surface.) replace brushes and done. check again in 10 years.

If your battery is only lasting 3 years most likely your cutout or regulator is out of adjustment. ( my Model A is going on12 years with same battery). If you have an original canister cutout pull it and use a 12v selectable power supply and see were its cutting off ($50 on amazon) Hook up positive and negative and turn up volts and see were it clicks.
check open or current draw and check it when closed for resistance. anything more than 6.5 vts it NEEDs to be adjusted.

both cutouts and regulators have a set of breaker points inside that need to be cleaned filed (just like ignition points They arch pit over time) and the air gap adjusted and the spring pressure adjusted for them to work correctly.


Derek G-
 
I have a Deka battery,been working about 10 years. It's on a 9n with only a cutout,but stays charged well. I've had a few cars with 6v and a vr and even back then,they went bad within a few years. If You can find a starter/generator shop,they'll fix You up.
 
8 gauge is no where near heavy enough for a 6 volt system. You need 0 or 00 as the battery cables
I am probably wrong on the size #. It's a typical battery cable. braided core is 7/16 or 1/2 inch diameter. The bolt goes through the dash support into the steering box. No sign of overheating and engine now starts on 3rd or 4th revolution.
 
I am probably wrong on the size #. It's a typical battery cable. braided core is 7/16 or 1/2 inch diameter. The bolt goes through the dash support into the steering box. No sign of overheating and engine now starts on 3rd or 4th revolution.
I would say you are off on the size. This chart may help you.

Battery cable chart.jpg
 
Voltage regulators have two sets of points in their so their is double that needs to be adjusted and Maintained, all it takes is the the back pressure spring being a bit week and staying closed at say 8 vts and you'll kill your 6v battery pretty quick. the big thing to remember is with the cutout we regulate our power voltage out at the generator adjusting the 3rd brush. But with a VR it regulates the power out at the VR. what's really common is that the points don't open enough because they don't have enough air gap and that combined with arch pitting can cause the power to jump across back feeding ever so slightly to the generator trying to make it "spin" even if not spin just slightly energize the field coils. So now you have a parasitic drawing down on the battery when off and if that gets combined with overcharging when running it makes for week starting, lack of cranking time, sometimes depending on how much its over charging excessive ignition point arching and early failure at ignition points and early failure on light bulbs.

the only thing i have that has a voltage regulator is my old Harley. every spring that gets pulled and checked and usually every two years it needs some adjustment.

For my tactor and model A witch have cutout cans i check those cans every other year and i set my generator a idle with headlights on using a multi meter at the batter making sure when running im only showing 6.1 on the battery. I generally run with headlights on all the time both for simplicity for charging and safety so people see me coming.
 
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