9S7976 SOLENOID ASSEMBLY--24 Volt Part of 6N1888 Electric Starting Motor Group shown on Page 60 Serial No. 35V909-Up 621B

Pos.	Part No	Qty	Parts name
1.	9M-7657 C	[4]	NUT-SEALING
2.	8S-8023	[1]	COVER AS
3.	8S-8024	[1]	GASKET-COVER
4.	9B-7235	[1]	SCREW-MACHINE
	9B-7233	[1]	LOCKWASHER
5.	8S-1528	[1]	BOOT
6.	8S-8021	[1]	CORE AS

			THE FOLLOWING REPAIR
			KITS ARE AVAILABLE:
	8S-1524	[1]	KIT-TERMINAL STUD (BATTERY)
	8S-1525	[1]	KIT-TERMINAL STUD (MOTOR)
	9S-8688	[1]	KIT-CONTACT END CORE
	8S-1527	[1]	KIT-YOKE END CORE
	C		CHANGE FROM PREVIOUS TYPE

#ZEBP05780061

6N-1888: STARTING MOTOR GP-ELECTRIC

STARTING MOTOR GP-ELECTRIC

6N1888 ELECTRIC STARTING MOTOR GROUP--Prestolite--24 Volt--Part 1
Part of 4N1062 Electric Starting Motor Group shown on Page 59
9S7976 Solenoid parts are shown on Page 59. Serial No. 35V909-Up

c156042 ZEBP0578

6N1888 STARTING MOTOR GP-ELECTRIC Parts scheme

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Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Pos.	Part No	Qty	Parts name
1.	1D-5117	[2]	NUT (jam)
2.	3B-4508	[6]	LOCKWASHER
3.	4N-9405	[1]	CONNECTOR
4.	4N-9404	[1]	LEAD ASSEM.
5.	2P-8819	[1]	KIT (Field Terminal Stud)
			(Includes Stud, Bushing & Washers)
6.	1D-4719	[4]	NUT
7.	9S-7976 Y	[1]	SOLENOID ASSEM.
			(Separate Illustration)
8.	6H-3622	[4]	SCREW
	3B-4504	[4]	LOCKWASHER
	3K-6116	[4]	WASHER
9.	4M-3217	[2]	SCREW
10.	4B-1220	[3]	SCREW
11.	8S-1553	[1]	GASKET
12.	3B-4502	[7]	LOCKWASHER
13.	1P-7831	[1]	HEAD ASSEM. (Commutator End)
14.	2B-4602	[1]	PLUG
15.	1P-7832	[1]	KIT (Bearing & Wick)
16.	4N-9403	[1]	KIT (Commutator End Terminal Stud)
			(Includes Stud, Bushing & Washers)
	Y		SEPARATE ILLUSTRATION

#ZEBP05780062

6N-1888: STARTING MOTOR GP-ELECTRIC

STARTING MOTOR GP-ELECTRIC

6N1888 ELECTRIC STARTING MOTOR GROUP--Prestolite--24 Volt--Part 2
Part of 4N1062 Electric Starting Motor Group shown on Page 59
Serial No. 35V909-Up

c207344 ZEBP0578

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Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Pos.	Part No	Qty	Parts name
1.	2P-8822	[1]	PLATE ASSEM.
2.	4N-9401	[1]	KIT (Includes 6 Brushes)
	2P-8868	[1]	KIT (Includes 8 Springs)
3.	2P-8825	[1]	SHIFT YOKE ASSEM.
4.	2P-8817	[1]	KIT (Yoke Adjusting)
			(Includes Plugs, Pin, Gasket & Nut)
5.	8S-1535	[1]	KIT (Includes 6 Plugs)
6.	4N-9402	[1]	KIT (Includes 10 Insulations)
7.	8S-4684	[1]	KIT (Bearing & Wick)
8.	8S-1543	[1]	HOUSING ASSEM. (Pinion)
9.	2B-4602	[1]	PLUG
10.	8S-4680	[1]	KIT (Includes 10 Seals)
11.	4N-4405	[1]	DRIVE ASSEM.
12.	2H-3931	[1]	SEAL
13.	2P-8824	[1]	HOUSING ASSEM.
	2B-4602	[1]	PLUG
14.	8S-2226	[1]	BUSHING
15.	8S-2225	[1]	SEAL
16.	0L-1340	[7]	SCREW
	2P-8816	[1]	KIT (Includes Housing Screws)
17.	3B-4504	[7]	LOCKWASHER
18.	4M-0189	[1]	SEAL
19.	2P-8818	[1]	KIT (Field Coil)
			(Includes Coils, Gaskets & Screws)
20.	8S-1546	[1]	ARMATURE ASSEM.
	8S-8075	[1]	KIT (Armature Thrust Washers)

#ZEBP05780063

4N-0957: STARTING MOTOR GP-ELECTRIC

STARTING MOTOR GP-ELECTRIC

4N957 ELECTRIC STARTING MOTOR GROUP--Delco-Remy--24 Volt--Part 1
Part of 4N1062 Electric Starting Motor Group shown on Page 59
6N5123 Switch parts are shown on Page 64. Serial No. 35V909-Up

c156037 ZEBP0578

4N0957 STARTING MOTOR GP-ELECTRIC Parts scheme

For full view, you need register

Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Part No	Qty	Parts name
		THE FOLLOWING REPAIR KITS ARE AVAILABLE FOR 1P2508 DRIVE ASSEM.:
9S-9825	[1]	KIT (cup)
4S-9459	[1]	KIT (washer)
1D-5117	[2]	NUT
3B-4508	[1]	LOCKWASHER
7F-3494	[1]	WASHER (.031 in. thick)
9H-3757	[2]	WASHER (.093 in. thick)
4M-1841	[1]	CONNECTOR
3L-3380	[1]	BUSHING
2F-2860	[8]	SCREW
3B-4501	[8]	LOCKWASHER
4M-0189	[2]	SEAL
4B-1220	[3]	SCREW
8H-0878	[3]	LOCKWASHER
7F-3529	[3]	WASHER
3S-2398	[1]	BUSHING
2B-4602	[1]	PLUG
9F-2547	[1]	WICK
		(Parts of 4M1844 Assem.)
2L-8166	[1]	WASHER
4M-1844	[1]	FRAME ASSEM.
7S-9826	[1]	PLUG
		(Part of 4M1844 Assem.)
4M-1845	[8]	BRUSH ASSEM.
7L-2894	[2]	GASKET
2N-3145	[1]	INSULATOR
4M-1831	[2]	PLUG
4M-1868	[1]	ARMATURE ASSEM.
4M-1839	[1]	COIL ASSEM.
9M-7606	[1]	PLUNGER ASSEM.
4M-1828	[1]	RETAINER
4M-0188	[1]	WASHER
4M-1829	[1]	BOOT
6H-3622	[4]	SCREW ASSEM.
6N-5123 CY	[1]	SWITCH ASSEM.
		(Separate Illustration)
8H-1141	[4]	SHOE
1H-2629	[2]	STRIP
1M-9971	[1]	SPACER
2F-6678	[1]	SEAL
1M-9968	[1]	BUSHING
		(Parts of 4S7899 Assem.)
9M-7609	[1]	SPRING
4S-7899	[1]	HOUSING ASSEM.
4M-1827	[1]	RETAINER
9M-7611	[1]	RING
3F-2617	[1]	NUT
4M-1854	[1]	SHAFT
1H-1023	[1]	SEAL .369 in. dia.)
2D-6392	[1]	SEAL (.239 in. dia.)
9M-7611	[1]	RING
4M-1853	[1]	LEVER ASSEM.
4M-1851	[1]	GASKET
1P-2508	[1]	DRIVE ASSEM.
		(800066)
		-OR-
6N-3826	[1]	DRIVE ASSEM.
		(480321)
9S-9771	[1]	PINION
9S-9770	[1]	SPRING
		(Parts of 2P4708 Assem.)
4M-1833	[5]	SCREW (1.50 in. long)
7M-0336	[1]	SCREW (.86 in. long)
4L-2729	[1]	WASHER
2B-4602	[1]	PLUG
9F-2547	[1]	WICK
		(Parts of 4S7899 Assem.)
C		INDICATES CHANGE
Y		SEPARATE ILLUSTRATION

#ZEBP05780064

4N-0957: STARTING MOTOR GP-ELECTRIC

STARTING MOTOR GP-ELECTRIC

4N957 ELECTRIC STARTING MOTOR GROUP--Delco-Remy--24 Volt--Part 2
Part of 4N1062 Electric Starting Motor Group shown on Page 59
Serial No. 35V909-Up

c119005 ZEBP0578

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Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Part No	Qty	Parts name
7F-4545	[1]	PLATE
5H-6467	[2]	MACHINE SCREW
7H-2079	[2]	LOCKWASHER
7F-3525	[2]	WASHER
9M-7652	[1]	PLATE ASSEM.
7F-4549	[2]	PLATE
3H-3697	[2]	PIN
7H-2079	[2]	LOCKWASHER
7F-3525	[2]	WASHER
7F-3512	[8]	SPRING
		(Parts of 4M1846 Assem.)
4M-1849	[1]	LEAD ASSEM.
7F-4556	[4]	BOLT
1L-4789	[4]	LOCKWASHER
7F-3491	[2]	WASHER
1D-4719	[1]	NUT
3B-4508	[1]	LOCKWASHER
1D-5117	[1]	NUT
3B-4508	[1]	LOCKWASHER
7F-3494	[1]	WASHER
4M-1846	[1]	PLATE ASSEM.
3F-0379	[8]	SCREW
2L-6679	[2]	PLATE
4B-1311	[2]	MACHINE SCREW
7H-2079	[2]	LOCKWASHER
7F-3525	[2]	WASHER
7F-4546	[4]	HOLDER
7F-3522	[2]	SCREW
7H-2079	[2]	LOCKWASHER
7F-3535	[2]	WASHER
7F-4550	[1]	PLATE
		(Parts of 4M1846 Assem.)
7F-4556	[5]	BOLT
1L-4789	[5]	LOCKWASHER
4M-1831	[1]	PLUG
7L-2894	[1]	GASKET
4M-1896	[1]	BUSHING
		(Part of 1S297 Assem.)
1S-0297	[1]	HOUSING ASSEM.
		THE FOLLOWING REPAIR KIT IS AVAILABLE:
3N-3763	[1]	TERMINAL KIT
		(Consists of Bushings, Insulators & Washers)

#ZEBP05780065

4N-2286: ALTERNATOR GP-CHARGING

ALTERNATOR GP-CHARGING

4N2286 ALTERNATOR GROUP
5S9088 Alternator parts are shown on Pages 65 and 66
Serial No. 35V909-Up

c163273 ZEBP0578

4N2286 ALTERNATOR GP-CHARGING Parts scheme

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Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Pos.	Part No	Qty	Parts name
1.	0S-1589	[1]	BOLT
2.	1D-5118	[2]	NUT
3.	9S-3784	[1]	BLOCK
4.	0L-1143	[1]	BOLT
	1D-4717	[1]	NUT
	5M-2894	[2]	WASHER
	3K-0925	[1]	SPACER
5.	1S-4589	[1]	ROD
6.	6N-6967	[1]	GUARD ASSEM.
7.	4N-8225	[1]	PULLEY
8.	0S-1587	[1]	BOLT 4.45 cm(1.75 in.) long
	2M-0849	[1]	WASHER 3.81 cm(1.5 in.) long
	0S-1585	[1]	BOLT
9.	6N-0073	[1]	VEE BELT
10.	5S-9088 RY	[1]	ALTERNATOR GROUP
			(Separate Illustration)
11.	9M-9811	[1]	WIRE ASSEM.
			(Includes)
	5P-6021 H		WIRE .31 m(12 in.)
	9F-3965	[1]	TERMINAL
12.	2L-8052	[1]	TERMINAL
	R		REMFG PART MAY BE AVAILABLE
	Y		SEPARATE ILLUSTRATION
	H		ORDER BY THE METRE

#ZEBP05780066

6N-5123: SWITCH AS-SOLENOID

SWITCH AS-SOLENOID

6N5123 SOLENOID SWITCH ASSEMBLY
Part of 4N957 Electric Starting Motor Group shown on Page 62
Serial No. 35V909-Up

c155235 ZEBP0578

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Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Pos.	Part No	Qty	Parts name
1.	4M-1816	[ 1]	TERMINAL ASSEM.
	4M-1834	[ 1]	PLATE
2.	7F-4907	[ 1]	STRIP
3.	3H-3681	[ 2]	NUT
4.	3B-4508	[ 4]	LOCKWASHER
5.	3H-3680	[ 2]	NUT
6.	7F-3494	[ 2]	WASHER
7.	4M-1836	[ 2]	INSULATOR
8.	4M-1837	[ 2]	BUSHING
9.	7F-4906	[ 1]	STUD (R.H.)
	4M-1835	[ 1]	STUD (L.H.)
10.	4M-2800	[ 1]	TERMINAL
11.	9S-4490	[ 1]	GASKET
12.	4M-5274	[ 1]	SCREW
13.	9S-4489	[ 4]	SCREW ASSEM.
14.	4M-3217	[ 2]	SCREW
15.	4M-1814	[ 1]	CONTACT ASSEM.
16.	3P-0072	[ 1]	CASE ASSEM.
17.	1F-0073	[ 2]	CLIP
18.	4M-1815	[ 1]	SPRING

#ZEBP05780067

5S-9088: ALTERNATOR GP-CHARGING

ALTERNATOR GP-CHARGING

5S9088 ALTERNATOR ASSEMBLY--Part 1
Part of 4N2286 Alternator Group shown on Page 64
Serial No. 35V909-Up

c202886 ZEBP0578

5S9088 ALTERNATOR GP-CHARGING Parts scheme

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Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Pos.	Part No	Qty	Parts name
1.	9S-2260	[1]	PLATE
2.	9S-2544	[4]	SCREW
3.	8H-0878	[6]	LOCKWASHER
4.	9S-2438	[2]	SCREW
5.	7H-2079	[7]	LOCKWASHER
6.	9S-2255	[1]	COVER
7.	9S-2262	[1]	GASKET
8.	9S-2246	[1]	LEAD ASSEM.
9.	9S-9830	[1]	SCREW
10.	8F-1326	[3]	WASHER
11.	9B-7233	[3]	LOCKWASHER (Shake Proof)
12.	9S-9829	[1]	SCREW ASSEM.
13.	4B-2043	[4]	NUT
14.	9S-2259	[1]	REGULATOR
15.	9S-2250	[1]	GROMMET
16.	9S-2011	[1]	SCREW
17.	1L-4789	[1]	LOCKWASHER
18.	9S-2389	[1]	STUD ASSEM.
19.	9S-2398	[1]	HOUSING ASSEM.
20.	9S-2393	[3]	DIODE
21.	9S-2397	[1]	COVER
22.	9F-2247	[1]	PLUG
23.	9S-2395	[1]	BEARING
24.	9S-2394	[1]	SEAL
25.	9S-2396	[1]	BUSHING
26.	9S-2007	[3]	SCREW
27.	9S-2301	[1]	INSULATION
28.	9S-2292	[1]	HEAT SINK ASSEM.
29.	9S-2300	[4]	INSULATOR
30.	9S-9830 C	[4]	SCREW
	9S-2247	[4]	WASHER (Spring)
	4B-4863	[4]	WASHER (Plain)
31.	9S-2542	[1]	SCREW
32.	9S-2437	[5]	SCREW
	9S-2013 H	[1]	KIT (Terminal Relay)
			(Consists of Bushing, "O" Ring & Hardware)
	9S-2012 H	[1]	KIT (Terminal Output)
			(Consists of Gaskets, Terminal & Hardware)
	9S-2290 H	[1]	KIT (Heat Sink)
			(Diode Junction Hardware)
	9S-2291 H	[1]	KIT (Heat Sink)
			(Positive Diode Hardware)
	C		INDICATES CHANGE
	H		NOT PART OF 5S9088 ALTERNATOR

#ZEBP05780068

5S-9088: ALTERNATOR GP-CHARGING

ALTERNATOR GP-CHARGING

5S9088 ALTERNATOR ASSEMBLY--Part 2
Part of 4N2286 Alternator Group shown on Page 64
Serial No. 35V909-Up

c113560 ZEBP0578

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Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Pos.	Part No	Qty	Parts name
1.	9S-2242	[1]	RACE
2.	9S-2248	[1]	FIELD COIL AND SUPPORT ASSEM.
3.	9S-2004	[1]	STATOR ASSEM.
4.	9S-2006	[1]	INSULATOR
5.	9S-2005	[1]	GROMMET
6.	9S-2014	[3]	CLIP
7.	9S-2302	[1]	ROTOR ASSEM.
8.	9S-2390	[1]	RETAINER ASSEM.
9.	9S-2391	[1]	SEAL
10.	9S-2256	[1]	GASKET
11.	9S-2261	[1]	COLLAR
12.	2F-5721	[1]	BEARING
13.	2P-5616	[1]	FRAME
14.	3B-4502	[4]	LOCKWASHER
15.	9S-2009	[4]	BOLT
16.	9S-2391	[1]	SEAL
17.	9S-2254	[1]	COLLAR
18.	9S-2252	[1]	SLINGER
19.	9S-2008	[4]	SCREW
20.	9S-2258	[1]	FAN AND BAFFLE ASSEM.
21.	7F-7621	[1]	WASHER
22.	2K-4821	[1]	LOCKNUT

#ZEBP05780069

8D-4450: DRIVE SHAFT GROUP

DRIVE SHAFT GROUP

8D4450 DRIVE SHAFT GROUP--Part 1
Serial No. 35V1 to 35V694

c151898 ZEBP0578

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Parts for your 621B WHEEL TRACTOR:

CATERPILLAR SIS

Pos.	Part No	Qty	Parts name
1.	8D-5044	[1]	CAGE
2.	6H-0189	[2]	STUD
3.	9D-2072	[1]	GUARD
4.	3B-1915	[2]	BOLT
5.	3B-4506	[9]	LOCKWASHER
6.	8D-4406	[1]	SPACER
7.	1T-0334	[1]	BEARING
8.	8D-4391	[1]	SPIDER
9.	8D-4396	[1]	SHAFT
10.	6D-7554	[2]	PLATE
11.	0S-1595	[4]	BOLT
	5F-9963	[2]	LOCK
12.	9F-1507	[2]	STUD
	1B-4204	[2]	NUT
13.	3B-4507	[12]	LOCKWASHER
14.	0S-1591	[4]	BOLT 1.50in.(38.19 mm) long
	5M-2894	[4]	WASHER
			-OR-
	2A-4639	[4]	BOLT 1.625 in.(41.15 mm) long
	5M-2894	[4]	WASHER
15.	8D-4394	[1]	RETAINER
16.	0T-0320	[8]	BOLT
17.	8D-4403	[1]	HOUSING
18.	9H-0846	[1]	SEAL
19.	0S-1588	[7]	BOLT
20.	8D-4395	[1]	COVER
21.	0L-0659	[1]	STUD
22.	4H-5232	[1]	PIN
23.	1D-4608	[12]	BOLT
	9D-5496	[12]	MOUNTING ASSEM.
24.	8D-5045	[1]	COUPLING ASSEM.
25.	1D-4719	[6]	NUT
	3B-4508	[6]	LOCKWASHER
26.	5S-3676	[1]	SEAL
27.	0L-1026	[2]	PLUG
28.	4F-6154	[2]	DOWEL
29.	2D-6533	[1]	SEAL
30.	1D-4556	[2]	BOLT 2.75 in.(69.85 mm) long
			-OR-
	0T-0319	[2]	BOLT 2 in.(50.80 mm) long