Stator Resistance Value

[miket0813]

My JD LX176 isn't charging. I wasn't seeing enough voltage at the stator connection when the engine was running. I am getting a .2 ohms reading across the 2 stator wires. No shorts. Is the stator the culprit? I am not sure about the ohms value.

 

[dickfoster]

How are you reading stator voltage? It should be an AC voltage which is then applied to diodes to rectify into DC voltage. You have a multi phase stator windings typically three or four which output AC voltages that is then rectified to a DC voltage. The output voltage is read by the voltage regulator which applies a proportional DC current to the rotor winding through some brushes. The output voltage is therefore regulated to something between 13 to 14VDC or enough to charge a 12V battery. Typically what fails are the brushes wearing out. Usually about a dollar ninety eight fix.

Typical alternator wiring.

 

[miket0813]

Shoot, I think I read the voltage on the DC setting...already yanked the stator out. Should have came here first! So you are thinking that the .2 reading with no shorts would indicate that the stator is fine? The failing brushes that you mention are on what component?

 

[dickfoster]

Shoot, I think I read the voltage on the DC setting...already yanked the stator out. Should have came here first! So you are thinking that the .2 reading with no shorts would indicate that the stator is fine? The failing brushes that you mention are on what component?

Usually the brush holders are on the removable back housing. The brushes rub the commutator ring on the rotor and pass DC current to the rotor winding which produces a rotating multiphase magnetic field that cuts through the stator windings to produce multiphase AC current.

 

[David_Kb7uns]

Thinking since the LX176 is a lawn mower that there are magnets on the flywheel and no brushes.

David

 

[dickfoster]

Thinking since the LX176 is a lawn mower that there are magnets on the flywheel and no brushes.

David

That could be. I was thinking it had a regular alternator. I never think of lawn mowers on a tractor site.

 

[joecdeere]

I have a PDF of the tech manual if you want it, all electrical test and drawings in it. Shoot me your email if you do.

joe

 

[CalG]

My JD LX176 isn't charging. I wasn't seeing enough voltage at the stator connection when the engine was running. I am getting a .2 ohms reading across the 2 stator wires. No shorts. Is the stator the culprit? I am not sure about the ohms value.

Ohms should be very low. The alternator is trying to push current!

Try a different test, .....

 

[mitch becton]

this john deere did came with magnetic alternator all it consist of is bearing and rotor the stator/rectifier/ regulator on some models bolt to back of alternator some are under the dash area it should be aluminum box with probably a wiring harness with 5/6/7 wires going to it these alternators are a poor excuse at best for long life this box not much bigger than pack of cigarettes might want to get joecdeere breakdown good lucjk