Contents Section: General Servicing - All Makes All sections

A/c Compressor Overhaul - 4-cyl Ford Bronco II I

General Servicing - All Makes 25 illustrations ~1480 words

DESCRIPTION

The Tecumseh HR980 4-cylinder, radial compressor is compactly packaged in a round, welded steel housing. Four pistons are actuated in their respective cylinder bores by a scotch-yoke mechanism, coupled to the compressor crankshaft.

Internal repair of the compressor is limited to replacement of shaft seal, seal seat, and pulley bearing.

Refrigerant lines are connected to the compressor with spring lock coupling type fittings. Special tools are required to disconnect the couplings.

A magnetic clutch drives the compressor shaft. When voltage is applied to the field coil, the clutch plate and hub assembly (attached to the compressor shaft) is drawn by the magnetic force toward the pulley, which rotates freely on the compressor body.

The magnetic force locks the clutch plate and hub to the pulley, causing the compressor shaft to turn with the pulley.

When voltage is removed from the clutch field coil, springs in the clutch plate and hub assembly pull the clutch plate away from the pulley. This causes the compressor shaft to stop rotating.

The compressor was first used on some 1983 models.

Note. Information on special tools required for servicing the Tecumseh HR980 compressor follows. Also appearing are instructions for replacing the shaft seal, pulley bearing, and clutch coil, as well as, instructions for leak-testing the compressor.

Exploded View of Tecumseh HR980 4-Cylinder Compressor Service is limited to shaft seal, seal seat, and pulley bearing replacement. Scheme 6

Scheme 6: Exploded View of Tecumseh HR980 4-Cylinder Compressor Service is limited to shaft seal, seal seat, and pulley bearing replacement.

SERVICE TOOL REFERENCE NUMBERS & PART NUMBERS

Reference Number (Tool Name) & ManufacturerPart Number
1 (Vise Holding Fixture)
DrafAC 1191
Robinair40545
RotundaT57L-500-A
2 (Clutch Holder Wrench)
DrafAC 499
MotorcraftYT-499
Robinair10781
RotundaT81P-19623-MH
3 (Clutch Hub Remover)
DrafAC 1011
MotorcraftYT-1011
Robinair10884
RotundaT80L-19703-B
4 (Pulley Spanner Wrench)
RotundaT83P-19623-A
5 (Shaft Seal Protector)
DrafAC 484
MotorcraftYT-415
Robinair10514
RotundaT71P-19703-H
6 (Pulley Puller)
DrafAC 451, 457, 1058
MotorcraftYT-457
Robinair10501
RotundaT71P-19703-B
7 (Pulley Installer)
DrafAC 1059
MotorcraftYT-1059
RotundaT80L-19703-J
8 (Dust Cap Remover/Installer)
Draf
RemoverAC 1194
InstallerAC 1194
Robinair10549
9 (Snap Ring Pliers - Internal)
DrafAC 923
Robinair14163
10 (Seal Seat Remover & Installer)
DrafAC 486
MotorcraftYT-486
Robinair10513
RotundaT71P-19703-M
11 ("O" Ring - Remover)
DrafAC 412
MotorcraftYT-412
Robinair10508
RotundaT71P-19703-C
12 ("O" Ring - Installer)
DrafAC 462
Robinair10509
RotundaT71P-19703-L
13 ("O" Ring - Guide & Sleeve)
DrafAC 460
RotundaT71P-19703-J, K
14 (Seal Remover/Installer)
DrafAC 415
MotorcraftYT-415
Robinair10503
RotundaT71P-19703-G
15 (Pressure Test Fitting)
DrafAC 1189
RotundaT83P-19623-B
16 (Spring Lock Coupling Tool)
DrafAC 1175
MotorcraftYT-1056
Robinair10968
RotundaT83P-19623-C & G
17 (Hub Installer)
DrafAC 1052
MotorcraftYT-1052
RotundaT80L-19703-F
18 (Clutch Pulley Support)
Motorcraft
W/ Warner ClutchYT-1064
W/ Nippondenso ClutchYT-1065
Rotunda
W/ Warner ClutchT80L-19703-E
W/ Nippondenso ClutchT81P-19623-J

TECUMSEH HR980 4-CYLINDER COMPRESSOR SERVICE TOOLS PART NUMBERS

REMOVE SHAFT NUT

Mount compressor on bench holding fixture. Hold clutch hub with clutch spanner wrench. Remove compressor shaft nut.

Tool Reference - No. 1 - Holding Fixture, No. 2 - Clutch Spanner Wrench

Remove Shaft Nut. Scheme 7

Scheme 7: Remove Shaft Nut

REMOVE CLUTCH HUB

Install clutch hub remover. Hold hub remover with a 1" wrench, while tightening bolt with a 1/2" socket wrench. Remove clutch hub and shims from compressor shaft, noting location and thickness of shims.

Tool Reference - No. 3 - Clutch Hub Remover

Remove Clutch Hub. Scheme 8

Scheme 8: Remove Clutch Hub

REMOVE PULLEY NUT

Using spanner wrench, remove pulley nut. Lift off pulley and field coil.

Tool Reference - No. 4 - Pulley Spanner Wrench

Remove Pulley Nut. Scheme 9

Scheme 9: Remove Pulley Nut

REMOVE PULLEY & FIELD COIL

If pulley and bearing assembly cannot be removed by hand, use shaft protector and puller.

Tool Reference - No. 5 - Shaft Protector, No. 6 - Pulley Puller

Remove Pulley & Field Coil. Scheme 10

Scheme 10: Remove Pulley & Field Coil

REMOVE KEY

To remove clutch hub key, grip it with a side cutter and pull outward.

Remove Key. Scheme 11

Scheme 11: Remove Key

REMOVE DUST CAP

Using a small screw driver or dust cap remover, pry dust cap from compressor.

CAUTIONUse care to prevent damaging end of compressor housing.

Tool Reference - No. 8 - Dust Cap Remover

Remove Dust Cap. Scheme 12

Scheme 12: Remove Dust Cap

REMOVE SEAL SNAP RING

Using internal snap ring pliers, reach down into compressor neck and remove snap ring retaining ceramic seal seat. Thoroughly clean inside of compressor neck, shaft, and exposed portion of ceramic seal seat.

CAUTIONDo not let any dirt or other foreign material enter compressor.

Tool Reference - No. 9 - Internal Snap Ring Pliers

Remove Seal Snap Ring. Scheme 13

Scheme 13: Remove Seal Snap Ring

REMOVE SEAL SEAT

Insert ceramic seal seat remover into recess of ceramic seal seat. Tighten outer sleeve to firmly expand tool in seat. Remove seat by pulling tool outward, with a clockwise twisting motion.

Tool Reference - No. 10 - Ceramic Seal Seat Remover/Installer

Remove Seal Seat. Scheme 14

Scheme 14: Remove Seal Seat

REMOVE "O" RING

Using "O" ring remover, lift "O" ring from inside compressor neck. Discard "O" ring.

Tool Reference - No. 11 - "O" Ring Remover

Remove "O" Ring. Scheme 15

Scheme 15: Remove "O" Ring

REMOVE SEAL

Insert compressor shaft seal remover tool into compressor neck so it rests on top of shaft seal. Rotate tool clockwise, while forcing tool downward, permitting tool tangs to engage seal. Pull tool from compressor neck. Discard seal. Clean compressor neck and shaft thoroughly.

Tool Reference - No. 14 - Seal Remover/Installer

Remove Seal. Scheme 16

Scheme 16: Remove Seal

Scheme 17

Scheme 17: INSTALL "O" RING
  1. Coat new "O" ring with clean refrigerant oil. Place "O" ring guide over compressor shaft. Insert "O" ring into "O" ring sleeve. Insert sleeve with "O" ring over "O" ring guide and into compressor neck opening. (Scheme 17): Install "O" Ring (1 of 2)
  2. Insert "O" ring installer over "O" ring guide and down into "O" ring sleeve. Allow "O" ring installer to bottom against guide. Then, raise "O" ring sleeve to allow "O" ring to slip into its correct installed position. Remove "O" ring guide, sleeve and installer from compressor neck.

Tool Reference - No. 13 - "O" Ring Guide & Sleeve, No. 12 - "O" Ring Installer

Install "O" Ring (2 of 2). Scheme 18

Scheme 18: Install "O" Ring (2 of 2)

INSTALL SEAL

  1. Install shaft protector over end of compressor shaft.

Tool Reference - No. 5 - Shaft Protector

  1. Coat shaft seal with clean refrigerant oil. Carefully engage tangs of shaft seal with slot in seal installer tool.

Tool Reference - No. 14 - Seal Remover/ Installer

Install Seal (1 of 2). Scheme 19

Scheme 19: Install Seal (1 of 2)
  1. Slide shaft seal and tool down compressor shaft, while turning tool. Apply light downward pressure until seal engages flats on shaft and is properly seated. Press down on tool and turn it to disengage tool from seal. Remove tool.

Install Seal (2 of 2). Scheme 20

Scheme 20: Install Seal (2 of 2)

Scheme 21

Scheme 21: INSTALL SEAL SEAT
  1. Coat ceramic seal seat with clean refrigerant oil. Insert ceramic seal seat installer into seal seat. Turn outer sleeve to grip seat. (Scheme 21): Install Seal Seat (1 of 2)
  2. Install seal seat, while rotating tool in clockwise direction. This will prevent dislodging "O" ring from its groove. Remove seal seat installer and shaft protector.

Tool Reference - No. 10 - Ceramic Seal Seat Remover/Installer

Install Seal Seat (2 of 2). Scheme 22

Scheme 22: Install Seal Seat (2 of 2)

INSTALL SNAP RING

Using internal snap ring pliers or "O" ring installer, install ceramic seal seat retaining snap ring. Install with flat face of snap ring against seal seat. Use "O" ring installer to press snap ring evenly into chamber until it snaps into its groove. To avoid damaging seal seat, do not bump or tap on snap ring.

Tool Reference - No. 9 - Internal Snap Ring Pliers, No. 12 - "O" Ring Installer

Install Snap Ring. Scheme 23

Scheme 23: Install Snap Ring

LEAK TEST SEAL

Before completing compressor assembly, install pressure test fittings on compressor. Install manifold gauge set and R-12 supply. Install shaft nut temporarily. With compressor in normal horizontal operating position, rotate compressor shaft several rotations by hand. Using a leak detector, leak test shaft seal. To remove pressure fittings, use spring lock coupling removal tool.

Tool Reference - No. 15 - Pressure Test Fittings, No. 16 - Spring Lock Coupling Removal Tool

Leak Test Seal. Scheme 24

Scheme 24: Leak Test Seal

INSTALL COIL, PULLEY & BEARING

Install dust cap in compressor neck. Install clutch coil on front of compressor with electrical connector on top. Fit slots of coil over housing lugs. Install pulley and bearing assembly on front of compressor. Bearing is a slip fit, and if properly aligned should slip easily onto compressor head. If necessary, tap pulley gently, using pulley installer and light plastic hammer.

Tool Reference - No. 7 - Pulley Installer

Install Coil, Pulley & Bearing. Scheme 25

Scheme 25: Install Coil, Pulley & Bearing

INSTALL PULLEY NUT

Apply thread locking compound to threads of pulley and field coil retaining nut. Using pulley spanner wrench, install and tighten nut. Using pulley spanner wrench, install and tighten nut to 65-70 ft. lbs.

Tool Reference - No. 4 - Pulley Spanner Wrench

Install Pulley Nut. Scheme 26

Scheme 26: Install Pulley Nut

INSTALL CLUTCH HUB

Install key in compressor shaft. Align keyway in clutch hub with shaft key. Using hub installer, install clutch hub and shims. If hub and pulley are being replaced, use 2 thickest shims from shim pack between hub and end of shaft.

CAUTIONDo not attempt to drive hub on compressor shaft as compressor shaft as compressor damage will result.

Tool Reference - No. 17 - Hub Installer

Install Clutch Hub. Scheme 27

Scheme 27: Install Clutch Hub

INSTALL SHAFT NUT

Using spanner wrench to hold clutch hub, install and tighten compressor shaft nut to 10-14 ft. lbs. Using a feeler gauge, check air gap at 3 equally-spaced locations between clutch hub and mating pulley surface. Smallest gap should be .021-.036". To adjust, add or remove shims between clutch hub and compressor shaft.

Tool Reference - No. 2 - Clutch Spanner Wrench

Install Shaft Nut. Scheme 28

Scheme 28: Install Shaft Nut

REMOVE BEARING

Perform steps 1-5 of "SEAL REPLACEMENT". Position largest opening of clutch pulley support over hub to support pulley. Drive bearing from pulley, using pulley installer.

Tool Reference - No. 18 - Clutch Pulley Support, No. 7 - Pulley Installer

Remove Bearing. Scheme 29

Scheme 29: Remove Bearing

INSTALL BEARING

  1. Place clutch pulley friction face on small opening of clutch support tool. Align new bearing over clutch bearing bore. Using pulley bearing installer, seat bearing.
  2. Stake bearing in bearing bore, using a blunt drift at 3 equally-spaced locations around bearing. Do not use previous staking locations. Perform steps 16-19 of "SEAL REPLACEMENT".

Install Bearing. Scheme 30

Scheme 30: Install Bearing

REPLACE CLUTCH COIL

To replace clutch coil, perform steps 1-5 and 16-19 of "SEAL REPLACEMENT" in this article.