the manual is a bit confusing to me on this. so far i've added + voltage to the S terminal, with the M terminal wire attached, and the piston ejects. the manual refers to this as the "pull-in" test. nothing happens unless the M terminal wire is attached. is this right?



also, can someone explain the "hold-in" test? is the piston supposed to remain ejected under certain circumstance? in the test above, the piston returns once i remove the voltage from the S terminal.



[i'm trying to determine if i actually need a new starter. when turning key the starter spins but engine does not rotate. motor does turn when done manually at pulley.]



p.s. sorry for using the word "piston"



thanks,

fritz

Here is how the starter works. you basically have 3 connections. The main connection from the battery to the starter soilinoid,the connection from the solionoid to the actual starter motor, and the "s" terminal wire that comes from the ignition switch. The wire from the battery has power all the time. When you turn the key to start the car 2 things happen in the starter, buth occour from 12v+ going to the "S" terminal. The first thing is it operates the soilinoid moving the plunger to engage the flywheel, at the same time the solinoid closes the contact between the wire from the battery to the wire on the started motor.





Now based on what you are saying, and the tests you did it sounds like the solinoid is fine, but the motor itself is bad. Are you sure you hear the motor spin when you turn the key?

i'm assuming the sound i hear is the starter activating but since i've taken it out none of my tests have made the pinion wheel of the starter spin..it ejects but doesn't spin...i'm not sure if i'm testing it correctly though. my initial thought was that the overriding clutch was slipping but i thought once the starter was removed from the flywheel the pinion would at least spin a little bit.



oh, after looking at these parts i have a question: how does the teeth of the starter pinion, which ejects and retracts, line up with the flywheel teeth when you start your car??



thanks for all the info,



fritz https://www.nopistons.com/forums/pub...IR#>/smile.png

it sounds to me like the main motor itself that spins that gear is bad.



I have a few questions... are you testing it in the car or out of the car?



well if it is in the car,,, there are 3 connections the large connection from the battery, the other large connection from soilinoid to starter motor, and the small connection from the ignition sw. If you run a wire from the battery to that small wire 2 things should happen, the gear should pop out(which yours does) and the motor should spin.



TO TEST THE MOTOR. instead of connecting 12v to the "s" terminal, connect to the large connection(soiliniod to motor, not the one from the battery) when you do this the starter motor should spin, and prob. make a big spark https://www.nopistons.com/forums/pub...IR#>/smile.png. if the motor spins, the internal connection in the soilinoid is bad, if it does'nt spin, the starter brushes are bad.



Her eis my cool diagram for you

The diagram is wrong, the start isnt connected to ground https://www.nopistons.com/forums/pub...IR#>/smile.png

HUH?

starter is removed from the car...i brought it to a place that repairs starters and they tested it and it spin and the guy put a piece of plywood against the gear to test for slippage but it didn't..he opened it up to look at the coils and said that it looked brand new (!!)



but it won't turn my motor (??) (yes, the battery's charged) the motor doesn't seem to be locked..hmmm https://www.nopistons.com/forums/pub..._DIR#>/sad.png

well if you can turn the engine manually(socket on front pulley method) then the motor is not locked. I would check the connections to the starter. if you have corrosion buildup that will create high resistance, causing less power to flow to the starter, thus it won't have enough power to turn the flywheel. Check battery connections, positive cable to starter, negative cable to body and engine. It is possible the ground witre bolt on the block may have came loose

good tips. bench testing is sometimes unreliable, block of wood hardly simulates engine cranking resistance. the nuts were not loose when you removed the starter were they? the cables not the mounting. check the batt terminals as mentioned alredy for tightness and corrosion