LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 1990 >> RX-7 Base, Automatic >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Overhaul - N4A-El, N4A-Hl & NC4A-El >> Transmission Reassembly

Transmission Reassembly

  1. Replace "O" rings and seals before reassembly. Lubricate components with ATF during reassembly. Use petroleum jelly to hold components in place (if necessary). Install manual plate and parking rod assembly (if removed). See 29 or 36. Note location of bearing, race and thrust washers. See 37 or 38.
  2. Lubricate and install low and reverse piston into main case. See Fig 4 . Low and reverse piston return spring free length should be .232-.244" (5.90-6.20 mm). See Fig 5 . Install piston return spring, thrust washer and one-way clutch inner race. Ensure return spring is centered on race, and tighten bolts to specifications. See TORQUE SPECIFICATIONS  .
  3. Install low and reverse clutch pack with steel plate first. Alternate between friction and steel plates, followed by retaining plate and snap ring. With low and reverse brake assembled, measure clearance between snap ring and retaining plate with feeler gauge. See RETAINER PLATE-TO-SNAP RING CLEARANCE SPECIFICATIONS  table under CLUTCH SPECIFICATIONS. Retaining plate is available in different thicknesses.
    Fig 1: Exploded View Of Transmission
    G93H23546Courtesy of MAZDA MOTORS CORP.
    Fig 2: Identifying Bearing & Race Locations (N4A-EL) Refer to the following table. Courtesy of Mazda Motors Corp.
    G93I23547
    OUTER DIAMETER DIMENSIONS FOR 37:

    Application (Location)(1) In. (mm)
    1 & 2 Bearing 2.756 (70.00)
    3, 5, 9, 10 & 11
    Bearing 2.756 (70.00)
    Race 2.756 (70.00)
    4 & 7
    Bearing 1.378 (35.00)
    Race 1.299 (33.00)
    6
    Bearing 2.756 (70.00)
    Race 2.756 (70.00)
    8 & 13
    Bearing 2.087 (53.00)
    Race 2.028 (51.50)
    12 Bearing 1.850 (47.00)
    (1) See Fig 2 .
    Fig 3: Thrust Washer, Bearing & Race Location (N4A-HL) Refer to the following table. Courtesy of Mazda Motors Corp.
    G93J23548
    OUTER DIAMETER FOR 38:

    Application (Location) (1) In. (mm)
    1, 2, 6, 7 & 8
    Bearing 2.756 (70.00)
    Race 2.756 (70.00)
    3 & 4
    Bearing 1.378 (35.00)
    Race 1.299 (33.00)
    5 & 10
    Bearing 2.087 (53.00)
    Race 2.028 (51.50)
    9 Bearing 1.850 (47.00)
    (1) See Fig 3 .
    Fig 4: Low & Reverse Brake Assembly
    G93A23549Courtesy of MAZDA MOTORS CORP.
    Fig 5: Checking Low & Reverse Return Spring Free Length
    G93E23550Courtesy of MAZDA MOTORS CORP.
  4. Check operation of assembled low and reverse brake by applying air pressure to oil passage. See Figure . Install bearing in rear of transmission. Install oil distributor with governor assembly and bearing race. Insert output shaft. N4A-EL does not use governor on oil distributor.
  5. Install connecting drum, internal gear and rear planetary pinion carrier as an assembly. Install the snap ring onto the output shaft. Check governor operation by applying air pressure to oil passage. See Fig 11 .
  6. Install extension housing, and ensure output shaft locks with manual lever in "P". Install speedometer pinion assembly. Install rear clutch assembly on top of front clutch assembly. Install rear clutch hub and front planetary pinion carrier in rear clutch assembly.
  7. Install connecting shell and sun gear from top of front planetary pinion carrier. Install clutch and front carrier as an assembly in transmission. Ensure bearings and/or thrust washers are installed in correct position.
  8. Place transmission on work stand with extension housing downward. To check and adjust total rear clutch end play, insert drum support bearing and race on rear clutch. Install a new drum support gasket in transmission. Measure and record distance "A". Measure and record distance "B" of drum support. See Fig 6 .
  9. Subtract distance "B" from distance "A" and record difference. Subtract .004" (.10 mm) from this difference to obtain total end play. Total end play should be .010-.020" (.25-.50 mm). If not within specifications, select different size bearing race.
    Fig 6: Measuring Rear Clutch (Distance "A" & "B")
    G93F23551Courtesy of MAZDA MOTORS CORP.
    Fig 7: Measuring Front Clutch (Distance "C" & "D")
    G93G23552Courtesy of MAZDA MOTORS CORP.
  10. With correct total rear clutch end play set, check and adjust total front clutch end play. Install thrust washer on front clutch. Ensure drum support gasket is in place. Measure and record distances "C" and "D". See Fig 7 .
  11. Subtract distance "D" from distance "C" and record difference. Subtract .004" (.10 mm) from this difference to obtain total front clutch end play. Total front clutch end play must be .020-.031" (.50-.80 mm). If not within specification, select different size thrust washer.
  12. Install 2nd brake band, strut and band servo. Tighten 2nd brake servo adjusting screw lightly. Install and center drum support on OD case. See OD CASE & DRUM SUPPORT  under COMPONENT DISASSEMBLY & REASSEMBLY. Install gasket on transmission case.
  13. Align matching marks on OD case and transmission case, and install OD case. Temporarily install 2 bolts to hold OD case in place. To check and adjust OD planetary gear total end play, position OD case upward.
  14. Install bearing and race. Install planetary carrier, sun gear and connecting shell as an assembly. DO NOT  install direct clutch at this time. Install bearing and race on connecting shell. Measure and record distances "E" and "F". See Fig 8 . On N4A-EL, install sensing rotor before measuring distance "E". See Fig 9 . Install a new oil pump gasket on OD case.
  15. Subtract distance "F" from "E" and record difference. Subtract .004" (.10 mm) from difference. Standard OD total end play should be .010-.020" (.25-.50 mm). If not within specifications, replace bearing race installed in drum support. See 43 and 44.
    Fig 8: Measuring Distance "E" (N4A-HL) & "F"
    G93H23553Courtesy of MAZDA MOTORS CORP.
    Fig 9: Measuring Distance "E" (N4A-EL)
    G93I23554Courtesy of MAZDA MOTORS CORP.
  16. When OD total end play is within specification, remove components from OD case. Check and adjust direct clutch end play by installing thrust washer in OD case. Install direct clutch, sun gear, connecting shell, bearing and race. On N4A-EL, install sensing rotor. See Fig 9 . DO NOT  install planetary pinion carrier.
  17. On all transmissions, measure and record distances "G" and "H". See Fig 10 . Subtract distance "H" from "G" and record difference. Subtract .004" (.10 mm) from this difference. Standard direct clutch total end play should be .020-.031" (.50-.80 mm). If not within specification, select different size thrust washer.
    Fig 10: Measuring Distances "G" & "H"
    G93J23555Courtesy of MAZDA MOTORS CORP.
    Fig 11: Air Checking Locations
    G93A23556Courtesy of MAZDA MOTORS CORP.
  18. Install intermediate shaft. Install intermediate shaft with long splines to front. Install OD brake servo assembly. Install OD brake band and strut. Install bearing and race, thrust washer and OD direct clutch assembly.
  19. Tighten servo piston stem to hold direct clutch in place. Remove 2 bolts holding OD case to transmission. Align matching marks, and install oil pump assembly. Install input shaft. On N4A-EL, install input shaft through oil pump. Install bearing, sensing rotor and snap ring. Install oil pump and input shaft as a unit on OD housing. Ensure input shaft is installed in proper direction noted during disassembly.
  20. On all transmissions, apply sealant to bolt flanges and bellhousing-to-OD case mating surface. Install "O" rings between converter housing and oil pump (if equipped). Align match marks and install converter housing. Tighten RETAINING bolts to specifications. Loosen OD servo piston stem lock nut and make adjustments according to the OD & 2ND BRAKE BAND ADJUSTMENT SPECIFICATIONS  table. Tighten the lock nut.
  21. Using Gauge (49 G032 355), measure depth "N" of vacuum throttle valve. See 47 and 48. Determine correct length of vacuum diaphragm rod. See VACUUM DIAPHRAGM ROD  table. Install vacuum diaphragm rod, "O" ring and vacuum diaphragm in transmission case. See Fig 13 .
    OD & 2ND BRAKE BAND ADJUSTMENT SPECIFICATIONS

    Application Specification
    Except RX7 & 929
    OD Stem Torque 60-86 INCH Lbs. (7-10 N.m)
    Back Off Turns 2
    2nd Stem Torque 102-128 INCH Lbs. (12-15 N.m)
    Back Off Turns 3
    RX7 & 929
    OD Stem Torque 102-120 INCH Lbs. (12-14 N.m)
    Back Off Turns 2
    2nd Stem Torque 102-128 INCH Lbs. (12-15 N.m)
    Back Off Turns 2 1/2
    VACUUM DIAPHRAGM ROD

    Measured Depth "N" In. (mm) Install Rod In. (mm)
    Less Than 1.010 (25.65) 1.14 (29.00)
    1.010-1.019 (25.65-25.90) 1.16 (29.50)
    1.020-1.039 (25.91-26.40) 1.17 (29.75)
    1.040-1.049 (26.41-26.65) 1.18 (30.00)
    1.050-1.069 (26.66-27.15) 1.20 (30.50)
    More Than 1.069 (27.16) 1.22 (31.00)
    Fig 12: Measuring Vacuum Throttle Valve Depth
    G93B23557Courtesy of MAZDA MOTORS CORP.
    Fig 13: Installing Vacuum Diaphragm
    G93C23558Courtesy of MAZDA MOTORS CORP.
  22. Air check the components to ensure proper operation. See Fig 11 . Install valve body assembly and tighten to specifications. On N4A-EL, install the solenoid valve electrical connector in the transmission case. Install new oil pan gasket and oil pan. Tighten to specifications. See TORQUE SPECIFICATIONS  . Install OD band servo cover.
  23. To complete reassembly, reverse disassembly procedure. Ensure torque converter is completely seated.
scientia non olet · About LEMON Manuals