FOUR SPEEED TRANSMISSION 7 I2 GENERAL DESCRIPTION A great deal of similarity and interchangeability now except the selector shaft and selector finger are located exists between the new 3 and 4 speed transmissions on the cover The backup lamp switch is located on the Only these 4 speed differences as they affect service cover position described under Corvair three speed will be covered here Other 4 speed service procedures transmission cover assembly are similar to the Corvair 3 speed transmission and The following parts are the same as those used in the are not repeated in this section Corvair three speed transmission cover head to shaft pins interlock and detent balls detent springs third and MAINSHAFT ASSEMBLY fourth shifter shaft the three speed second and third Asssmsly srsssssrss s ssss mss ssssr Cssvss mss ELf biZh H a3 Z Z ZSdSZZ Y f E Sii F Z E Speed Transmission also apply to this transmission and fork assembly However the synchronizer assembly at the front of the Disassembly and Assembly Procedures are Covered mainshaft is used for the third and fourth rather than the th t second and third shift The synchronizer assembly at the m XS SGC mn rear of the mainshaft is used for the first and second rather than the first and reverse shift Gear teeth cut in CASE the first and second synchronizensleeve distinguish it The Case has a finer plug Opening On the right hand from the third and fourth synchronizer sleeve All parts side It provides for six bolt attachment to the carrier except the gears and the first and second synchronizer Holes are added to the Corvair three speed transmission Sleeve m the new fouhspeed tmnsmlssmn mamshaft case to accommodate the familiar reverse inhibitor assembly are also used in the Corvair three speed th f dt 1 H transmission mainshaft assembly However starting parts used m 9 Our Spee mnsmlssmns On y me essary these parts may be removed by punching out the from the front gears on the mamshaft are third second two case welsh plugs Sec View On Fig 1B Cmss and first rather than second first and reverse A fourth Section blocker ring is used between the 1 2 synchronizer as sembly and first gear on the four speed transmission REVERSE IDLER GEAR PARTS M EL ANE US This is a sliding reverse idler gear and shaft retained t Thisfr msmission includes the COISYSSY three speed by a woodruff key Elimination of the thrust washer be mmsmlssmn Clutch gear bearing retamem gasken SE tween the ggar and Case and addition Of 8 Snap ring Stop lector shaft and selector shaft seal A new selector to limit forward movement of the reverse idler gear dis fmger has bee deslgned to both Engage th Shlfter hgad tinguishes this shaft from the three speed transmission SSISMOY Slots in the Cm r as WGH as the reverse m reverse idler shaft Otherwise service procedure is the h1b1tOr located m the base sf the CaS same as for the three speed transmission TOOLS COVER ASSEMBLY The same dummy countershaft Tool J 22246 used with The cover on the new four speed transmission is lo the three speed transmissions can also be used with the cated on the left hand side of the case All shift controls four speed transmission MAINTENANCE AND ADJUSTMENTS SIDE COVER ASSEMBLY Fig 2B 3 Insert interlock pin in the hole of the interlock detent in the longest of the shafts with three detents the Dliuslgirgrlelyout the three roll pins retaining the shifter third Snd fourth Ehaftx Insert the Sham three detents heads tO their Shafts first into the middle hole of the left hand boss of the 2 Withlupper and lower shifter shafts in neutral detent Egg igiggagggefgggiiugggggsEgg 2 r Ss positions remove the center shifter shaft and head bl The third d f th h ft h d d k by sliding the shaft through the cover bosses y an Our S 1 er G an for as 3 Remove the other two Shit h ft sembly has a larger fork than the first and second 1 Sr S S S SSS hSSdS Shifter head and fork assembi it can be identified 4 glimggje 30 Sggpplj 1 3 s t r i sg 2 by the shaft hole between the Zotch and the selector 3 4 Shifter Shaft 4 ilsgemble the third and fourth shifter head and fork Assembly assembly over the shaft with the fork hole to the 1 Turn inside of cover up so that single attaching hole fight hand side and the selector slot downward on flange is at the top 5 Complete insertion of shaft through the right hand 2 Drop a poppet spring and ball in each of the two boss while lining up the shaft detents with the detent holes in the right hand boss of the cover All detent ball Stop at the 2nd neutral speed detent springs are identical all detent and interlock balls 6 Line up holes in head and shaft insert roll pin All are identical head attaching pins are the same Fig 3B CORVAIR SHOP MANUAL SUPPLEMENT