Longer Clutch Rod - C2

[Mike G.]

With more and more of us having problems with insufficient adjustment travel on our clutch rods.... I would hope that one of our repro sources (Paragon, LICS, etc.) will soon offer the most direct solution - a longer rod.

I'd be one of the first customers. Let's see if they're gathering market research by frequenting this board.

[Michael H.]

Re: Longer Clutch Rod - C2

Mike,

If you have had problems with clutch adjustment since one/several of the clutch components have been changed on your car, you most likely need the later 66-67 clutch rod that connects the clutch pedal to the cross shaft. The 66-67 T.O. bearing and release fork were different than 64-65 and these early style items are no longer available. Both have been replaced in service with the 66-67 parts. The patch is the longer 66-67 rod, part number 3888213. (I think) I believe this part is still available from GM and is reasonably inexpensive.

[Ray C.]

Re: Longer Clutch Rod - C2

I had posted earlier that I was have problems with not enough linkage adjustment length after installing a NAPA clutch. I installed a LUK clutch (actually said Corvette on the box) yesterday and now have a full pedal and enough treads for adjustment. I am wondering with the amount of import parts now being used if the problem is not with the clutches.

Ray

[Michael H.]

Re: Longer Clutch Rod - C2

Ray,

There may ALSO be some problem with the newer clutches but the linkage problem goes back decades. I remember this particular problem from the late 60's and it even showed when using all new GM parts, including the pressure plate. Almost the entire clutch linkage system was redesigned for 66 and most of the 64-65 parts were then discontinued. The "adjustment at the end of the rod" deal is not at all new.

[John H.]

Re: Longer Clutch Rod - C2

Although the throwout bearing remained the same (1-1/4"), the combination of upper and lower pushrod lengths changed, and must be correct in order to maintain the pedal free play adjustment. The '63-'65 upper pushrod grew from 18" to 19-1/4" for '65 396 and all '66-'67, and the lower pushrod got shorter by 1.2" (10.2" in '64-'65, 8.6" for '66-'67). Not sure what the length of the one-year-only ball-end '63 lower pushrod was.

[Ray C.]

Re: Longer Clutch Rod - C2

Hi! John

As per your advise I replaced the Napa clutch with a LUK clutch. When I matched the Napa clutch system & bearing with the LUK set up there was less that 1/8" difference, NAPA slightly shorter. After installing the LUK clutch the pedal met resistance at the top of the pedal, where as the NAPA clutch met restistance about an 1 1/2" above the floor.

Thanks for the help!

Ray

[Mike G.]

Re: Longer Clutch Rod - C2

John: Many thanks for providing the actual dimensions! Nothing like having the data! Now I'll be able to identify what's in the "bubba-mobile" that I'm working on, and know what I need to replace. Mike

[Michael H.]

Re: Longer Clutch Rod - C2

The 64-65 T.O. bearing was 1 7/32", which later became the 1 1/4". The big change inside the clutch housing was the T.O. arm and also the pivot ball. The 64-65 was unique and replaced in the early part of the 66 model run with the new 66 and later design. If any of these parts are mixed, there will be some problems with clutch adjustment ranging from minor to severe, depending on the combination of parts used. I've been there many times.

The lower rod for 64-66 327 was the 10 9/16" OL 3844209. This same part for 65-66 396-427 was the 8 37/64" OL 3872960. The short 960 was used on all 67's, both 327 and 427. Supposedly, no 64-66 small block originally used the short lower rod, at least according to the parts books.

Also, the lever assy (cross shaft) changed along with the rest of the newly released parts for 66, to correct the dimensions provided by the other new parts.

If the short 8" rod is required on a 64 or 65, something is wrong somewhere.

[Michael H.]

Correction...Typo

The lower rod info should have read the long 10 9/16" 3844209 for all 64-65 327, NOT 64-66. Sorry.

The shorter 8 37/64" was used for all 66-67, both 327 and 427.

[Mike G.]

Thanks to All

Speaking on behalf of all who have endured the heartbreak of too short a ...er rod --thanks for breaking the code on this pesky issue.

[John G.]

Re: Thanks to All

Keeping true to the 'while you're in there' mantra of replacing parts I ordered up a new lower rod and swivel from LIC. Both of the original items that came off my car were worn almost halfway through their diameter (at the ends that go into the cross shaft). The parts that arrived from LIC appeared to be exact repro's of the originals that were on my '64.

After the clutch was adjusted with the new lower rod and swivel installed there was an extra 3/8 inch of thread showing at the end of the upper clutch rod. Previously, there were 0 threads showing.