Should i have a continuity reading from the power lug on my 9n starter to the frame? i have removed the slipcover and the armature turns freely but when i put a battery charger set on jump across it it does nothing

The field is notorious for failing in these tools -
If you remove the cap on the field housing you can access the field wires - check to see if you have continuity through the field windings.
To further investigate
1) Remove the brushes and inspect them for excessive wear or chipping (If they look burnt or are chipped the armature is suspect)
2) Remove the 4 screws holding the field assembly to the saw frame
3) Pull the field off and inspect the armature (especially the commutator (copper segments the brushes ride on) for burnt or raised segments or windings.

Remove the cap on the end of the motor and remove the 2 carbon brushes. (Ensure the brushes move freely in the tubes and contact the armature)
Remove the 4 screws holding the motor housing to the frame and pull it straight off. Check the copper commutator on the armature and make sure it is not burnt.

If armature and brushes look fine my guess is you have a bad field (very common problem in this tool) #1619PA5590

http://www.ereplacementparts.com/bosch-4000-0601476139-table-saw-parts-c-128_167_168.html

Hope you have remove now. Remove the 2 mounting bolts. Then,
dip starter down and inward to clear the flywheel.

Type you tube on Goggle. Then type 9n tractor- starter removal
View the viduo

You have one of two problems: Either the starter drive on your starter is defective and is not engaging the flywheel to crank the engine, or the flywheel has some broken or damaged teeth that are preventing the starter from engaging.
Starters come in a variety of designs. On some, the solenoid is mounted on top of the starter. When you turn the key, the solenoid routes current to the starter motor and at the same time pulls a lever that slides the drive gear mechanism out so it will engage the flywheel and crank the engine. If the solenoid is weak or damaged, it may not be strong enough to overcome the spring tension that retracts the drive gear. So the starter spins but doesn't crank the engine.
On other starters, the solenoid is mounted remotely. When the starter motor starts to spin, it ratchets out so the drive gear will engage the flywheel and crank the engine. If the drive mechanism is damaged or hung up, the motor may spin but not crank the engine.
Regardless of what type of starter you have, it will have to come out for further inspection. The drive gear (which is sometimes referred to as a "Bendix drive") should move out when the starter starts to spin. The drive gear usually has a one-way clutch that is supposed to protect the starter against damage if someone keeps cranking the engine once it starts. The gear should turn one way but not the other. If the gear is locked up or turns freely either way, the drive is bad and needs to be replaced. If the drive can't be replaced separately, you'll have to replace the entire starter.
Starter Testing If the drive seems okay, the starter should be "bench tested" using jumper cables or special equipment designed for this purpose.
CAUTION: Be careful because a starter develops a lot of torque. It should be held down with a strap or clamped in a vice (be careful not to crush or deform the housing!) before voltage is applied.
A simple no-load bench test can be performed with a battery and a pair of jumper cables to see if a starter motor will spin. But this test alone won't tell you if the starter is good or bad because a weak starter that lacks sufficient power to crank an engine at the proper speed (usually a minimum of 250 to 500 rpm) may still spin up to several thousand rpm when voltage is applied with no load.
A better method of determining a starter's condition is to have it tested on equipment that measures the starter's "amp draw." A good starter should normally draw a current of 60 to 150 amps, depending on the size or power rating of the starter. Some "high torque" GM starters may draw up to 250 amps, so refer to the OEM specifications to make sure the amp draw is within the acceptable range.
If the starter does not spin freely, or draws an unusually high or low number of amps, it is defective and replacement is required.
An unusually high current draw and low free turning speed typically indicate a shorted armature, grounded armature or field coils, or excessive friction within the starter itself (dirty, worn or binding bearings or bushings, a bent armature shaft or contact between the armature and field coils). The magnets in permanent magnet starters can sometimes break or separate from the housing and drag against the armature.
A starter that does not turn and draws a high current may have a ground in the terminal or field coils, or a frozen armature.
Failure to spin and zero current draw indicates an open field circuit, open armature coils, defective brushes or a defective solenoid.
Low free turning speed combined with a low current draw indicates high internal resistance (bad connections, bad brushes, open field coils or armature windings).

My goodness I just saw your post and I see it has been around since Dec 2010. Your post appeared after I answered a much newer post. (site operates in this manner)

Anyway if you have a 1986 generator and you have 12V DC to the starter with the key on the most likely problem is the brushes in the starter PN: 31215-ZE2-003 or 31215ZR2003
http://ssl.jackssmallengines.com/jacks-checkout/shopping-cart.aspx?CFID=179837&CFTOKEN=92541317

The only problem I have is that I do not know if this is a set or an individual brush. Use the toll free phone number on the link above to confirm quantity.

Once you have the starter removed use some 220 grit or above sand paper and clean up the copper contacts on the starter armature and lubricate the bearings.

If you do a continuity test of the armature using the copper contacts your meter leads must be exactly 180 deg from each other (opposing) to get a resistance reading.
Reading out the stator winding is a matter of reading the + lead terminal to the case.

Thanks for choosing FixYa,
Kelly

I need more info on the truck sutch as year make model engine trans auto or manual .

hi, if just taking the rear wheels off the vehicle, you will need a hydraulic jack, or vehicle lift of some kind, jack stands to place under the vehicle if you are using the hydraulic jack. You will also need either a 4 way tire iron, or some combination of a 7/8 in socket and a 1/2 in drive breaker bar, the socket needs to be 1/2 in drive as well. this tools maybe rented from local auto parts stores if you do not have availible. now, the lug nuts(the nuts holding the wheels on) may not be 7/8 inch size, depending on the rim package you have, there will be only five of course though. before you jack up the vehicle, you must break the lug nuts loose. take either the 4-way tire iron, or the breaker bar and use a lot of force and turn counter clockwise with the wheels on the ground, and the vehicle in park, with the parking brake on. break all five lug nuts loose(able to turn easily, by hand if desired) on both sides. then you must locate the vehicle frame underneath, and use the jack on the frame point only, never on the axleshaft or body part, and jack up one side of the vehicle until the wheel hangs freely, and place a jackstand next to the hydrualic jack close to touching the frame. lower the vehicle onto the jackstand and make sure the wheel will hang freely. repeat on the other side until both sides, wheels are hanging freely. then remove the lug nuts with either the tire iron, socket and breaker bar, or by hand. once all lug nuts are reomved, pull the wheels off. that should just about do it, hope i didn't leave anthing out, if putting back on, reverse steps, but hand tighten clockwise until tight against the studs, then lower the vehicle down and tighen each lug nut in a star fashion. make sure to tighten very well, you don't want the rims to fall off while driving. good luck.

You need to compress the front of the drive enough to drive out the roll pin,then the drive should slide right off.

Starter - REMOVAL & INSTALLATION
Starter removal on some models may necessitate the removal of the front support which runs from the corner of the frame to the front crossmember. If so, loosen the mounting bolt which attaches the support the frame first, then remove the crossmember bolt and swing the support out of the way.

The starters on some engines require the addition of shims to provide proper clearance between the starter pinion gear and the flywheel. These shims are available in 0.015 in. sizes from Chevrolet dealers. Flat washers can be used if shims are unavailable.

1. Disconnect the negative battery cable.
2. Raise and support the vehicle safely using jackstands.
   

If access to the wiring is difficult, the starter may be partially lowered before disconnecting it, but be careful not to stretch or damage the wiring.

1. Disconnect all wiring from the starter solenoid. Replace each nut as the connector is removed, as thread sizes differ from connector to connector. Note or tag the wiring positions for installation purposes.
2. If equipped, remove the front bracket from the starter. On engines with a solenoid heat shield, remove the front bracket upper bolt and detach the bracket from the starter.
3. Remove the starter mounting bolts. If a starter shim tab can be seen protruding out from between the mating surfaces of the starter and the block, remove the outer bolt first, then loosen the inner bolt. With the outer bolt removed and the inner loosened, most shims may be grasped and pulled from the top of the starter at this point. Once the bolts are removed, lower the starter front end first, and remove the unit from the car.

If no shim tab could be seen, yet shims or flat washers fall from the starter as it is withdrawn, stop and attempt to determine their locations. If possible, gather the shims for reuse during assembly. Shims without tabs must be positioned on the starter prior to installation, but the bolts may be held through the starter assembly in order to hold the shims in position.


To install:

1. If flat washers or shims without tabs were found on removal, position them on top of the starter using the mounting bolts to hold them in position.
2. Position the starter to the engine block and loosely install the mounting bolts. If tabbed shims were withdrawn during removal, position them before the outer mounting bolt is threaded.
3. Once the starter and shims are properly positioned, tighten the two mounting bolts to 25-35 ft. lbs. (34-47 Nm).
4. If equipped, install the front bracket and/or heat shield to the starter assembly.
5. Attach the starter wiring to the solenoid, as noted during removal.
6. Remove the jackstands and carefully lower the vehicle.
7. Connect the negative battery cable.

STARTER OVERHAUL
Drive Replacement

1. Disconnect the field coil straps from the solenoid.
   
2. Remove the through-bolts, and separate the commutator end frame, field frame assembly, drive housing, and armature assembly from each other.
   

On diesel starter, remove the insulator from the end frame. The armature on the diesel starter remains in the drive end frame. On diesel starters, remove the shift lever pivot bolt. ON the diesel 25 MT starter only, remove the center bearing screws and remove the drive gear housing from the armature shaft. The shift lever and plunger assembly will now fall away from the starter clutch.

1. Slide the two piece thrust collar off the end of the armature shaft.
2. Slide a suitably sized metal cylinder, such as a standard 1 / 2 in. pipe coupling, or an old pinion, onto the shaft so that the end of the coupling or pinion butts up against the edge of the pinion retainer.
3. Support the lower end of the armature securely on a soft surface, such as a wooden block, and tap the end of the coupling or pinion, driving the retainer towards the armature end of the snapring.
4. Remove the snapring from the groove in the armature shaft with a pair of pliers. Then, slide the retainer and starter drive from the shaft.

To assemble:

1. Lubricate the drive end of the armature shaft with silicone lubricant and then slide the starter drive onto the shaft with the pinion facing outward. Slide the retainer onto the shaft with the cupped surface facing outward.
2. Again support the armature on a soft surface, with the pinion at the upper end. Center the snapring on the top of the shaft (use a new snapring if the original was damaged during removal). Gently place a block of wood flat on top of the snapring so as not to move it from a centered position. Tap the wooden block with a hammer in order to force the snapring around the shaft. Then, slide the ring down into the snapring groove.
3. Lay the armature down flat on the surface you're working on. Slide the retainer close up on to the shaft and position it and the thrust collar next to the snapring. Using two pairs of pliers on opposite sides of the shaft, squeeze the thrust collar and the retainer together until the snapring is forced into the retainer.
4. Lube the drive housing bushing with a silicone lubricant. Then, install the armature and the clutch assembly into the drive housing, engaging the solenoid shift lever yoke with the clutch, and positioning the front of the armature shaft into the bushing.
   

On non-diesel starters the shift lever may be installed in the drive gear housing first. On the 25 MT diesel starter only, install the center bearing screws and the shift lever pivot bolt, and tighten securely.

1. Apply a sealing compound approved for this application onto the drive housing; then position the field frame around the armatures shaft and against the drive housing. Work slowly and carefully to prevent damaging the starter brushes.
2. Lubricate the bushing in the commutator end frame with a silicone lubricant, place the leather brake washer onto the armature shaft, and then slide the commutator end frame over the shaft and into position against the field frame. Line up the bolt holes, then install and tighten the through-bolts.
3. Reconnect the field coil straps to the MOTOR terminal of the solenoid.
   

If replacement of the starter drive fails to cure improper engagement of starter pinion to flywheel, there are probably defective parts in the solenoid and/or shift lever. The best procedure would probably be to take the assembly to a shop where a pinion clearance check can be made by energizing the solenoid on a test bench. If the pinion clearance is incorrect, disassemble the solenoid and shift lever, inspect, and replace worn parts.

Hope this help.