<VV> 4spd Input Shaft, was Drivetrain Compatability

[kenharri at comcast.net]

From: Geoffrey Stozek <gjjs at att.net> 
Subject: Drivetrain Compatability 
Geoffrey Stozek writes,  "The 64/65 input shaft is larger in diameter than the 62/63 shaft so you must use 
the 64/65 input shaft with the 64/65 trans.? Also, if you use a 164 CI motor you 
need to use the 64 rear motor mount." 



I write, 



Exactly!  The '63 and earlier 4spd have a slightly smaller diameter input shaft with only 12 splines on the forward end.  When the 164 CI motor came out in '64 they beefed up the 4spd input gear and shaft to deal with the increase in torque.  The '64-'65 input shaft has 14 splines on the forward end.  



Last year I was ignorant to this fact.  I installed a good condition '64 4spd in place of the ailing 4spd in my Greenbrier.  The van is a '64 so I assumed the 4spd was also a '64  (I know, I know).  Everything went back together fine (it seemed).  It started right up and sounded great until I let the clutch out.  The van would not move and and a buzzing sound started and did not stop when I put it back in neutral.  I let it run for about 2 minutes while I investigated the sound.  I shut it down, closed it up and went back to the books.  After a week and popping the front cover off both transmissions, I  discovering my folly .  



When I removed the power train again I found most of the 12 spl ines from the shaft had been turned into shavings and luckily the input gear in the transmission was stronger metal and the 14 splines i nside of  it had not been damaged.  What a mess!   I flushed  out the trans and after replacing the 12 spline shaft with the correct 14 spline shaft was back in bussiness.  After a couple hundred miles I removed the trans again to inspect it.  I ended up doing a complete teardown and replaced the forward roller bearings and idler shaft due to wear.  It still had shavings floating around.  



The moral for me was, use your Junkyard Primer and Clarks catalog to figure out exactly what you have and exactly what you need.  If you are changing from one thing to another make sure you understand the compatability issues, check the VV archives and/or bounce it off this group.  Do not assume anything (if only I could remember this one)!   



Happy Corvairing  



Kent Harrington 

'64 Greenbrier, '63 Monza Vert 

Corvair Owner Since October 2009