charging help

[whtractors24 3,335]

Just got a 1978 c81 been sitting a long time was resrored years back reads 12.2 when off and same when running. So I started it disconnected the 3 prong connector from voltage reg it reada high 16s to 18v coning in and mids 12s going out. The amp meter stays direct in middle never moves? Also tried jumping rhe meter maybe thought bad meter not that. .. is it possible that the battery is shot?? Or has a bad cell..

[Jeff-C175 7,206]

 

disconnected the 3 prong connector from voltage reg it reada high 16s to 18v coning in

 

You were measuring AC VOLTS, and the meter connected to the two wires from the stator, correct?

 

Was the engine at 3600RPM ?  That seems on the low side to me...

[billjenner 1]

_{Hi, I have a 161 and someone had fitted a voltage gauge to years ago, then gave up and dumped it cos the battery was always flat. I  found out that the tractor should of had an amp gauge not volt gauge apparently this makes a difference as the wiring is different. anyway I fiited a amp guage and problem solved.}

[ARK 9]

Stop everything, disconnect battery, keep wires from alternator clear and not grounded.

 

Check battery and fully charge it off the tractor, then read voltage after sitting a couple of hors...should be 12.7 or higher

 

If the cells are open type use a hydrometer and test S.G.specific gravity 1.0 is pure water, a fully charged wet cell battery is 1.25 all cells.

 

Now with a clean tested fully charged battery hook it back up to clean tight connectors and start the engine.  With a known good meter read the voltage at the battery terminals and to ground.  Voltage should be higher than 12.7.  14.45 to 14.7 at the highest, Any higher the regulator is shot, lower than 12.7 is just battery and no alternator voltage.

 

Alternators are AC devices that must be rectified.  Rectification is the work of the AC to DC convertor