Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

[Jace H.]

It is getting more and more difficult to get my 64 original M20 Four Speed into reverse. Once I get it there all is fine. All other gears shift smoothly. It's just getting that reverse lockout up and into reverse is a struggle. Any suggestions before I pull the transmission?

Thanks,
Jace Holt
28944

[Jim T.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

With the engine off is hard to shift into reverse?

[Dino L.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Adjust your shifter per the service manual.....basically you put a gage in the shifter body and remove the reverse lever from the tranny side cover screw it in and out until it easily fits over the bolt and mating surface, then tighten the locking nut....2 min job with the body off, 2 hr job if the body is on.....my 62 gage can be bought from part houses, not sure on Gage's for C2 or c3 shifters.....the C3 has the taller handle....

[Gary H.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Any time I have issues with the lockout on my 69s m20 I shift into first and then into second and then into reverse. Works like a charm.

[Leif A.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Any time I have issues with the lockout on my 69s m20 I shift into first and then into second and then into reverse. Works like a charm.

That's the old "back in the day" fix. And it does seem to work every time.

[Jace H.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

No difference with engine on or off!

[Duke W.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Make sure you have correct freeplay per the CSM. The reverse gear set are spur type gears (That's why they whine) with a sliding gear and no synchronizers. If everything is in good working order and properly adjusted you will always get a little clash if you shift quickly from neutral to reverse because the countershaft is still spinning. If you first shift to a forward gear as mentioned previously, the synchonizer will stop the countershaft and reverse will engage without clash.

This procedure is called "clearing the gears", but if the clutch linkage has excess freeplay, which can cause it to not fully release you will always get clash.

So it's likely either a clutch adjustment issue or a linkage adjustment issue, and you should check both.

You don't really need the gage block to adjust the linkage. Remove the shift boot and check that the notches in the levers are lined up. If reverse is a little off, adjust the rod length as required to line the reverse lever up with the other two. The procedure is in the 1963 Corvette Shop Manual and there may be additional information in the 1964 Supplement.

Duke

[Jace H.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Thanks Duke!

[Domenic T.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Jace,
Unscrew the ball and remove the lock out rod and try it. If it works smoothly then it's only a simple rod problem.

Dom

[Gene M.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Jace,
Unscrew the ball and remove the lock out rod and try it. If it works smoothly then it's only a simple rod problem.

Dom

Yes, if you have a replacement lock out T then it may be a bit too long causing it to not allow the lever to shift all the way over thus not clearing the gates for the forward gears. Easy check with the console plate and boot removed to see from the top.

I made my own "key gage" using .042" thick metal strip that is .628" wide ( I attempting mind recall on the number so it may be off) and 2 1/2" long with a hole at one end for a key ring for easy removal.

[John H.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Jace -

Here's what the bottom end of that reverse lockout rod looks like, and the stud it has to clear when you pull up on the "T"-handle in order to get into the reverse gate.


RevLockoutPin1 [800x600].JPG

[Jace H.]

Re: Getting Harder and Harder to get my reverse lockout into reverse - 64 Coupe

Thanks John!