64 305E Clutch Not Engaging
 

I'm finishing up rebuilding a 64 305E. I have this clutch installed: https://www.rockauto.com/en/moreinfo...&pt=1993&jsn=9

It's a 3-on-the-tree and I don't think the clutch is fully engaging. The clutch linkages all adjusted as far as they go. Also have a new clutch fork. When I have it in gear and hold the clutch and engage the brake, the engine dies. (It's on jack stands right now.)

Any recommendations? I'm not sure how to proceed from here. This is the last thing before getting the truck back on the road (first time since 2000).

Re: 64 305E Clutch Not Engaging
 

Please explain what the test was.
Push clutch pedal in, start motor, put in gear, let clutch pedal out, wheels start turning, push on brake, motor dies??????? that would be normal.......or what is the sequence?
Please list each step like I did in my example. It sounds like you get it started and in gear but I don't know what "hold the clutch" means. Puch clutch pedal in like coasting, then apply brakes and motor stops. That would be "clutch not DISengaging"

Re: 64 305E Clutch Not Engaging
 

Push clutch pedal in, start motor, put in gear, let clutch pedal out, wheels start turning, *push clutch in*, push on brake, motor dies

Re: 64 305E Clutch Not Engaging
 

Correct, that's what I think is happening. It's in gear, the wheels are turning. I push the clutch in and then press the brake in and the engine dies, so the clutch is not disengaging the engine?

Re: 64 305E Clutch Not Engaging
 

Yes, the adjustment rod needs adjusted to be "longer" to push fork lever more towards rear of truck. Therefore rocking fork forward and pushing throwout brearing deeper into clutch release springs.
It is possible that you have some components installed incorrectly. Sometimes throwout bearing is installed backwards by installer. Reducing it's "reach".....or put the disc in backwards....or throwout bearing facing correctly but flange not "under" the spring clips....and so on. These things WILL cause your failure to disengage problem. You say you have run out of adjustment so the items mentioned are possible.

Re: 64 305E Clutch Not Engaging
 

I checked the throw out bearing, and it's good. Are adjustment rods available anywhere? Or, do you think I'd have luck fabricating a longer adjustment rod?

Re: 64 305E Clutch Not Engaging
 

I added some info, check it.

You checked the T/O bearing and it's good? Well something is wrong somewhere right? so you missed something right?

If you are all stock, you need to figure out what you did wrong or if you bought the correct stuff. If you start chasing your tail, then the clutch won't engage all the way and you will wear it out fast.

The clutch in our club list says 11" disc. Also shows a long and a short throwout bearing. Don't know what is correct. The Rockauto MU18621 shows application for GMC as 1961-1963. Has really good info at scroll down. Videos and pics of right and wrong install info. (hypertext links)

Re: 64 305E Clutch Not Engaging
 

Here's some pictures. I removed the cotter pin prior to photo. Do i have the linkage backwards?

https://uploads.tapatalk-cdn.com/202...ffd1b3dc75.jpg
https://uploads.tapatalk-cdn.com/202...7be694e05d.jpg
https://uploads.tapatalk-cdn.com/202...888dc44e1b.jpg
https://uploads.tapatalk-cdn.com/202...6775f7472f.jpg

Re: 64 305E Clutch Not Engaging
 

And some photos of the truck... https://uploads.tapatalk-cdn.com/202...2ade530157.jpg
https://uploads.tapatalk-cdn.com/202...0876d7075e.jpg
https://uploads.tapatalk-cdn.com/202...8828035b08.jpg
https://uploads.tapatalk-cdn.com/202...309ac95c7b.jpg
https://uploads.tapatalk-cdn.com/202...5c538430a5.jpg
https://uploads.tapatalk-cdn.com/202...bfd72da344.jpg

Re: 64 305E Clutch Not Engaging
 

Looks like your missing the wedge



https://www.ebay.com/itm/30476267078...mis&media=COPY

Re: 64 305E Clutch Not Engaging
 

Ordered it!


Sent from my iPhone using Tapatalk

Re: 64 305E Clutch Not Engaging
 

1. 64 has mechanical Z bar clutch mechanism.

2. The rods have been swapped. Hooked rod goes from pedal to Z bar. The other is the Z bar to fork rod.

SEE THIS LINK
https://www.lmctruck.com/1960-66-che...clutch-linkage

Re: 64 305E Clutch Not Engaging
 

There seem to be a couple different bell cranks used for Chevy V8, L6, 4x4 but, the GMC V6 is unique per this link.

It's a great read.

http://www.67-72chevytrucks.com/vboa...tures66+gmc+v6

I think JoelNC has the unit set up correctly minus the missing wedge.

Re: 64 305E Clutch Not Engaging
 

The linked post #37 seems to show what the LMC link shows.
JOEL: To answer your question, I believe you do have the linkage backwards. That post shows a 1964 305. It seems to have a different Z bar mounting bracket. There is a whole bunch of confusing stuff in that thread and elsewhere. Swap your rods and see what happens.

Re: 64 305E Clutch Not Engaging
 

Thanks so much for the reponses! The wedge is showing up today and I'll get the linkage swapped around and hopefully be on the road!

Re: 64 305E Clutch Not Engaging
 

I think you're right. I think I'm just missing the wedge. The link you provided shows that the GMC V6 setup is completely different from any of the Chevy or GMC L6 setups. My setup pushes the clutch fork, rather than pulling the clutch fork. The LMC diagram is different than what I have.

Re: 64 305E Clutch Not Engaging
 

I don't know of any GM clutch forks that are pulled. Can you post one?

Re: 64 305E Clutch Not Engaging
 

Sorry, I wasn't clear. It appears from the diagram here https://www.lmctruck.com/1960-66-che...clutch-linkage, when you press the clutch pedal, the z-bar is pulled up which pushes the clutch fork.

On my setup, when I press the clutch pedal, my z-bar is pushed down, which pushes my clutch fork.

There's a good comparison between the two setups here: http://www.67-72chevytrucks.com/vboa...tures66+gmc+v6.

Re: 64 305E Clutch Not Engaging
 

It seems like you likely have this figured out, but I thought I would just ask that you are sure this clutch is correct. In this other thread:

https://6066gmcclub.com/showthread.php?t=47796&page=4

A lot of people were having trouble with the collar being backwards and the spline protruding on the opposite side from the stock clutch. Sometimes people were installing them backwards by accident because of this. Did you have that problem at all? I have been looking for a clutch for my 65 and was only looking for the Rhinopac 04-528 because it sounded like that was the only one that didn’t have that problem and actually fit.

I’m just wondering what this was like for you, because if it all works and lines up then I have a solution for my own problem, but it also might be contributing to your troubles if it was not something you had been aware of.

Let me know how it all fit together for you.

Re: 64 305E Clutch Not Engaging
 

I may have the wrong clutch in there. I've found some little things that were off, like the z-bar was a little bit out of where it needed to be, and the clutch fork ball stud was a little bent, but I think it may be the issue in the thread you shared.

I'm going to mail my original clutch to the Brake & Clutch Supply in Bruceville, TX (254-752-4307). He says he's refaced a number of clutches for these GMC V6's. We'll see how it goes!

Thanks for responding!

Re: 64 305E Clutch Not Engaging
 

Im glad I could help, but I admit I am a little sad I was right. I was hoping for an easier answer to my own problem too! Good luck with yours!