6 V starter on a B

[55 50 Ron]

What should be the resistance from the copper clad terminal to the starter frame if it's working correctly? Using my Fluke 73 III, I get .4 ohms (point four). Seems too low, but then it is supposed to draw heavy current under load so maybe it's OK.

I'm asking because it was working, then the external switch shorted internally and I thought the starter may now be bad. If necessary, I'll take it to a professional starter shop.

Thanks

 

[old]

On most VOMs the ohm reading will be very low if not zero if all is as it should be

 

[Randy G]

Like old stated, the field stud should have no continuity with the starter frame. If there is then thats a short.

 

[wore out]

(quoted from post at 19:15:45 04/04/21) Like old stated, the field stud should have no continuity with the starter frame. If there is then thats a short.

Randy, take a deep breath or two and think about this, then post back!

Also, your mention of "field terminal" would make a person think you are refereeing to a generator rather than a starter.

 

[55 50 Ron]

6 volts and .4 ohms provides 15 amps of current. Seems to me the starter current will be much higher than 15 amps under load so the starter is probably OK.

And I've never had my Fluke multimeter calibrated so .4 ohms could be somewhat lower but not totally zero.

In general starter current is high and resistance is low. That's why we say large cables are needed for good battery power, especially with 6 volt batteries.

 

[Randy G]

wore out,

Well, I called it a field STUD cause its soldered to the field coils. Otherwise you lost me?

 

[John T]

Hey Ron, I think its SERIES WOUND unlike a Shunt wound Generator so current passes in series through BOTH Fields and Armature.

John T

 

[John T]

Ron, on many meters at extreme low resistance the readings are not perfect accurate. The resistance of those copper field and armature windings are very low but sorry I don't have any specs or dats of their actual value. There shouldn't be any shorts to case/frame OTHER THEN the final ground termination and I believe its SERIES wound versus Shunt like in the Generator.

If a switch stuck/burned close and it drew high current a long time it may have developed a short in Fields or Armature. Does it pass the smell test ?? I have seen wires or solder melted on the Armatures commutator segments as well as Fields burned and shorted to case/frame.

I would check voltage on the starter under load to see if there's any excess line/cable/terminal/connection Voltage Drop and/or the battery is weak. Of course extreme low voltage even if battery and cables and connections and grounds are allllllllll good may be due to a shorted starter

I think the voltage under load and the possibility of a short are more informative then an ohm check

John T