l lll li bearing rearward out of end frame Clean end frame 400 gipit dor finer lpolishing cloth Thoroughly clean I in clean solvent awaY ust partic es c To rinstall new bearing back up t l1e inside 4 The stator can be checked as follows L area of the end frame surrounding the bearing with a Connect a l2 volt test lamp or an Tool J 88lO camshaft gear remover ohmmeter from a stag lelidn to the stgtor frame If the lamp lights or V e o meter rea ing is ow l mess on closed end of needle Wmng umd the winding is grounded and the stator must be i beam lg is Hush mth the mdfmmc h uSmg I r laced If lamp does not light or there is no e Install 6 new retainer and felt Washer mth olipmmeter reading inf mite obtained the stator is M J 5lS8 2 until retainer seats against bearing not grounded 2 Wash metal parts except stator and rotor in it cleaning solvent Degreasiug solvent w 1 damage the Ohmlkleggnggiwees ea li 0l e lat0larl 2 dS Gif La rotor and stator insulation The rotor and stator lam mls to light or the Ohmmem madmggs high W Shwld be cleaned with wmpressed ai betxlsreen any pair of leads the stator wind ing is 3 Check the mlm s f H WS o en and the stator must be replaced Fig 12 3 a To check rotor for grounds connect Aa P C A Shan circuit in the smopwmdmgs is T 12 v test me 0 Mm Mm e P intent to rm without mn tea equipment A ring to the rotor shaft or poles If the lamp lights due to me Ow resistance of me Wmdmgi ll gt the Ohmnmm wading is 10W the Hfd However if all other electrical checks are norrnal T2 ggounded and the rotor must be rep ace 13 and me gepcmor mls to Supply meg gptpuh it b To check rotor for opens connect the test gwgkmdlcmon that the smm Wm mg me ll lamp I an Ohmmem lead t h shp m8 if the 5 Check rectifier bridge for a shorted or open 1 mP dw 1 9 d maroon Refer to Rncrmek BRIDGE riasr i obtained on the ohmmeter the field winding is 6 Ingpect the drive cndfmme bwmg for r open and the rotor must be replaced Fig l2 2 mugbnasp l tcuscxroxonouunst 7 Inspect brushes and brush springs Brushes i OHMMETER springs connectors and brush holder are serviced as an assembly l l t 8 Inspect drive end frame bearing retainer plate Q felt lf felt is hard or worn the retainer plate should be replaced ll v llwgp 9 Inspect insulation on the one brush holder lll ipaq mountingp screw lf insulator sleeve is missing or i i damaged it should be replaced l 5 t5 E rsl l RECUFIER BRIDGE TEST Fig 124 lll at There are 3 positive diodes in the insulated heat ll reurcrcrouorsnn M wr 1 Mars r l 7 OHM es Q t V Mx ng l toil 7 sux k ll M O ll lf U E tw 1 l l 0HMM sR AT a m r ip A is tcnrcxronsuoarsaunoreus yy lr mw 1 rg 1z 2 cneexaag new l o r U M Lj ggggird ll c To check rotor for short circuits connect a Y l l l 12vvolt battery and an ammeter in series with the Ws Q ay y l two slip rings The ammeter should read 2 2 to ix f 2 6 amps all rotors except 63 amp and internal g y V V regulator generators which should read 4 to 4 5 L amps If ammeter reading is higher than specified Z j 2 the field windings are shorted and the rotor must e r be replaced d The slip rings on the rotor can be cleaned l with 400 grit or fmer polishing cloth When cleaning slip rings the rotor must be rotating to V prevent flat spots on the slip rings which could OHMMHER cause brush noise OHMMFVER Slip rings which are rough or out of round should WECK EN l be trued in a lathe to a O02 maximum indicator reading After turning slip rings in a lathe polish with Fig I2 3 Checking Stator I sv i Il