C2 65/66 BB Clutch Rod

[Robert T.]

Has anyone had to "trim down" their clutch rod to avoid having the rod and the pedal mounting bracket attaching bolts from coming in contact? Right before my pedal hits the floor, one of the bracket mounting bolts hits the clutch rod and tends to push it off the pivot point. I talked to someone locally and they had to do the same thing. They ground down their rod a bit. While at Barrett-Jackson last week I was able to feel around under a couple of BBs and sure enough, they too had the rod trimmed/ground down. Is this "normal".

Thanks for any insight offered.

Bob

[Wayne M.]

Do you have that thick washer in place ?

The one that is shown in '65 AIM UPC 7, sheet C2. I know what you mean about the contact / wear and I've seen it in small block cars as well, but I wonder if it's just due to "slop" in the movements.

Specifically for '65-66 BB's, do you have the correct push rod pedal bracket #3872963, with the pin higher up opposite the crotch of the pedal stop ? Do you have your bracket set to quick or normal pedal travel / effort ? Sure you have the correct pedal push rod (thru the firewall ?)

[Joe L.]

Re: C2 65/66 BB Clutch Rod

Bob-----

I've never encountered this problem but I'll offer a few thoughts.

First of all, I'm assuming that you're talking about the PEDAL pushrod. Early 1966 used pedal pushrod GM #3819154 and later used GM #3888213. These pushrods have somewhat different dimensions, so if you're replacing a GM #3819154 with a GM #3888213, that may be the source of the problem requiring the slight t*******. If your car is a later 1966, then it should have had the 3888213 to begin with. However, also keep in mind that the "flattened" end of the rod might have changed over the years even though the part number did not change. I've noticed that later-manufactured SERVICE parts sometimes have a "wider" flattened area at the pivot point.

Another thought is this: 63-66 Corvettes use a bolt-on bracket on the clutch pedal for the clevis pin pivot. 1967 used a welded-on bracket. GM changed this design for a reason; they didn't do it because the earlier style worked just as well. The problem that they were trying to eliminate might very well have been exactly the problem you're experiencing.

[Joe L.]

Re: Do you have that thick washer in place ?

wayne-----

Yes, the pushrod spacer (thick washer) is also a possible source of the problem as is the pedal bracket. Curiously, the pedal bracket is one of those "little things" that someone "converting" a 1965-66 small block to big block might forget about.

[Wayne M.]

Here's a C2 clutch system variables "map"

With all the part #s throughout the 5 midstyle years, this is the only way I can keep it straight. And there's yet another factor; the throwout bearing.

This might help in the earlier clutch threads below.

[Robert T.]

Re: Here's a C2 clutch system variables "map"

Wow! Thanks for all the responses and the great picture/drawing. To answer some of the questions.
1. I'm coverting from an auto to a 4 speed
2. The pedal bracket bolt head hits the rod about 1-2 inches before the rod turns flat at the mounting point of the pedal.
3. I think I have the bracket in the normal position, but I'll ahve to check to be sure.
4. Those different rod part numbers are interesting. I have the 3888213. This is an early, #1478, car. Sounds like I need a 381954. I wonder what the difference is.
5. Wayne, can you elaborate a little on your reference to the throwout bearing. I did install all new clutch hw.

Thanks again for any help.

Bob #22650

[Joe L.]

Re: Here's a C2 clutch system variables "map"

Bob------

The 3819154 was 18" in overall length with a dimension of 17-9/16" from the tip of the threaded end to the centerline of the pivot hole. The GM #3888213 is 19-3/16" overall length with a dimension of 19" from the tip of the threaded end to the centerline of the hole. Regardless of which rod your car was originally built with, the 3888213 should service it, although you might have to do the t******* you mentioned. I don't know of any source for the 3819154, anyway.

The original release bearing used for your car was 1-7/32" long. That bearing was discontinued years ago and replaced by one of 1-1/4" long. The 1-1/4" long bearing is the only one available today. I know of no source for the 1-7/32" bearing. At least, I don't know of any source that has them for sale.

Your car also used a clutch fork ball stud that was 1-3/8" long. That stud was discontinued years ago and replaced by one that is 1-1/2" long. I don't know of any source for a 1-3/8" ball stud.

[Robert T.]

Re: Here's a C2 clutch system variables "map"

Thanks for the additional info, Joe. Sounds like my system should work. I know the car got hit on the left side, low in the front. Nothing major, but maybe the frame got tweaked a little. I had it checked, but we are probably only talking about 3/8 of an inch interference.

Oh well, time to get the grinder out.

Bob

[John H.]

Re: Here's a C2 clutch system variables "map"

Bob -

Do you have the THICK spacer washer in place on the pivot pin between the pedal end of the pedal pushrod and the bracket? If that spacer is missing, you WILL have interference.

[Robert T.]

Re: Here's a C2 clutch system variables "map"

Hello John,

Yes, I have that spacer in place. Good question. It's weird that I have seen this issue on a few cars now. Something must "add up" to cause this problem. Maybe the frame, maybe wear in the pedal assy (though it has been gone through)Maybe just some other stack up. I assume they didn't do any grinding in the factory. I guess I can work around it, but it would have been nice not to have had any issue. Thanks for the response.

Bob