I took out the 26 pickup and noticed that the amp meter /Gen (6 volt with cutout) showed -5amps at idle and +3 at speed. Figures could be + or - 2 volts. On disconnecting the battery I noticed a small spark. Today reconnected the batt and the amp showed -3. Without motor running Disconnected 25 amp accessory fuse and no change. Disconnected the gen and it went away. Dirty Gen or bad Gen? I am stumped.
What kind of cutout/regulator are you running?
It was on the car. This is something that just started. Battery seems to not want to charge. I changed it. It was 1 year old.
If you have an original points style cut out (sounds like it is), the points will sometimes stick and show a discharge with the motor not running (not good). With the amp readings your brushes and commutator may need attention and maybe the 3ed brush adjusted. Mine at idle reads 0 amps. Your amp meter should be set at about
+4-5 (maybe +6 if you drive with your headlights on during daylight hours) amps at an engine speed of around 20 miles per hour.
I have an original style old replacement cutout, maybe once a year or less the points will stick, I grab a screw driver and take the battery wire off and tap on the case and hook it back up. Has worked so far.
Thanks. Just went out to the barn and tapped the cutout and voila no more -3 now 0. I suppose I should order a new one.
Do yourself a favor, do not buy another relay type cutout. They are troublesome by design. Get a FunProjects voltage regulator or good quality diode conversion cutout replacement.
If you would like to discuss give me a call.
To. The Coilman
Another vote here for the Fun Projects voltage regulator. It makes the stock 6 volt battery/generator system so utterly reliable that I want to drive my T to work everyday. That part looks totally correct as well.
If you get the fun projects cutout be sure to follow the directions exactly. Especially checking the third brush adjustment the next day. Unfortunately the ammeter for the 26 and 27 years is not very good or accurate. If you could temporarily use an better ammeter for the adjustment you will be better served. The fun projects ammeter for older cars is far superior to any of the 26/27 units original or repro. It is a bit pricy for test equipment but will yield good results.
I work on Model T electrical charging systems every day and most original Model T dash ammeters are unreliable at best. To address this problem I made a simple tool using a FunProjects dash ammeter that can be temporarily installed during set-up of the FunProjects voltage regulator. The test leads are easily installed in series with the yellow wire from the engine compartment terminal block to the starter motor foot switch. As John pointed out careful attention to the FP VR installation instructions are necessary and with this tool you can obtain accurate reading.
You can easily make one for your shop. Notice the hooks to hang it on the radiator support rod when in use
Ron the Coilman