55 Bird starter resistance question.


http://forums.y-blocksforever.com/Topic137446.aspx 		Print Topic | Close Window

By 55charliebird - 7 Years Ago
I have a starter on the bench and a starter in the engine.  Both of them read between 0 and .1 ohms . Point 1 ohms is practically dead short.  I'm reading from the battery post to the starter case.  Is that about normal?  I'm sure it is going from bat. post through brushes through armature to ground.  Would you take a measurement and post it?  Thanks.
By 55charliebird - 7 Years Ago
To clarify what I need........take a resistance reading from the "hot" post on the starter to one of the mounting bolts on the starter.  Resistance reading i'm getting is 0 to .1 ohms.  Point 1 is practically dead short.  I have 2 starters with the same readings.  Thanks. 









By FORD DEARBORN - 7 Years Ago
That low resistance reading is pretty close to correct. A starter is a series machine of very heavy copper/low resistance windings.  Once up to operating speed, the resistance is much greater, due to developed counter emf.which is why that "dead short" doesn't remain a dead short when cranking the engine.  A 6V starter would be of even less resistance than a 12V starter but most digital meters are not very accurate much below a couple ohms. Sorry, I don't have a 6V starter on hand to measure but it would show what would appear to be a dead short. Hope this helps, JEFF.............
By 55charliebird - 7 Years Ago
Thanks Jeff, that makes me feel better.  I dismantled the starter on the bench, cleaned it, reassembled it.  Then it wouldn't spin......it did before.  So that's what made me measure the resistance.  I thought I put the short in it..  Dismantled and reassembled it again.  Same low resistance reading.  I'm going to try hand crank engine today, before I pull the starter on the engine.  I went direct from new batt. with jumpers to engine starter....no go.  Time to bite the bullet.
By FORD DEARBORN - 7 Years Ago
With the starter motor indicating aprox. 1 ohm, there should have been a good healthy spark when attempting to spin it with jumpers directly from the battery.  If not, then there's an open circuit somewhere?
By 55charliebird - 7 Years Ago
Correct.  Both starters (one in engine and one on bench) had a healthy spark.  The one in engine I hit it batt. voltage.....nothing.  Time to change it.