Anyone have experience with a worn out Z-Bar on a manual clutch? I have a brand new clutch, fork, and throwout bearing on my '79. The clutch pedal started binding and squeaking very loudly about a month ago. Last week I had a "pop" under my foot and now it feels like there is barely any pressure against the pedal about half-way through travel. The exterior spring is still attached to the fork, and the car still shifts and drives but it definitely "feels wrong". I haven't driven it since this happened to limit any damage. The mechanic at the transmission shop is telling me the Z-Bar needs a rebuild but I'm not sure if that is the entire problem.

 

The pop scares me. You should be able to look down and see the Z bar, it runs between studs on the frame and the engine block. You can google a picture. You can have someone push the clutch and watch the bar. One in good shape will only rotate. If it moves back and forth then it needs to be repairs. The only other parts that can cause slop in the system is the pivot to the pedal or the rod between the pedal and the Z bar. I have never seen that.

Z bar failure is common if you upgrade your clutch. The one in may 74 failed in 1983 and it broke the stud off in the block and I had to pull the engine to drill out the broken stud. That is why the pop would scare me. Once I got the Zbar itself out I found the stud wore most of the way through the bar so the bar had to be replaced any ways. I did not know the Zbar needed to be greased. If I had done that when I put the new clutch in I may have avoided the failure. It was a 3200lb pressure plate.

 

I was able to locate the Z-Bar and it appears to still be connected everywhere. Its kind of difficult to see because there's very little room to view anything in there, I've got long-tube hooker headers. It appears like the engine mount side is still in one piece but I can' get a viz on the body mount side. Its directly under the brake master cylinder. I can feel around with my hands on all the parts and everything seems to be there. But I can't see if something broke somewhere or came loose or something. I can't tell the full rotation of the bar either, it may have some side to side movement in it which is causing the slop in the pedal.

I didn't realize you could grease those either until I started looking for new Z-Bars online and saw they had zirc fittings on them. I lubed this one up and it feels a little better. But something is still up. I'll post results when I hear from the shop.

 

The 79 should have motor mount that will not allow a lot of engine movement if the rubber rips to wears out. It has a steel wrap around safety loop to keep the motor safely in place. This makes it hard to see if the mount has failed. If it is sloppy I could see that causing a bind with the Zbar. Having someone that knows how much an engine should move watch the motor as you let out the clutch is the best way to check these mounts while it is still in the car. You could also try to jack up the engine to check the movement, just don't jack it by the oil pan.

If you end up needing to pull the header then doing the motor mount may be worth it anyways if they are older. The driver's side is the side that will lift up while the passenger's side tries to push down. .

On a side note in the 60's the factory did make motor mounts with the safety loop. In high powered cars if the driver's side motor mount would break the engine could rotate. This would stretch the throttle cable and cause the car to go wide open throttle. As you can imagine this was very dangerous. GM had a recall and put a steel cable on the engines to the keep it from rotating too far. A lot of people took them off because they did not understand what they were for. I can tell you from personal experience it is pretty scarry to pull out in traffic and goose the throttle and then just feel the throttle disappear from the bottom of your foot and the car go nuts. Luckly my 67 is a stick. I pushed the clutch as part of stopping in an emergency, With the clutch pushed the engine fell back in place. I could really see if it was an automatic someone panicking and freezing,

 

Wow, that's incredible. From my previous post, I meant the motor mount side of the Z-Bar, not the motor mount itself.. So far I don't think there are any issues with the mounts themselves. However this is not the original engine, it was a 5.0 from the factory. Somewhere along the line the motor was changed to the current 350 (can't say I blame them).

 

Got the Z-Bar rebuilt and back in the car. Much smoother pedal but something was still "off". After ripping out the seat and diving under the dash I saw a broken neutral safety switch dangling from the pedal assembly. It then wiggled its way into the clutch linkage and caused all kinds of binding/jamming issues. Popped that out (it wasn't working anyway) and noticed that both the brake and clutch pedals are super wonky. Looks like the plastic bushings are toast. Any recommendations on kits to rebuild these? Or will any old set of bushings do?

 

https://www.ebay.com/itm/13258406594...3ABFBMqKLkqt5j

 

Got the pedals out from under the dash. Numerous upside-down ventures and a few cuss words revealed that the bolt washer was installed with the nut instead of the bolt head and allowed the bolt to free-spin inside the clutch pedal sleeve when trying to loosen the nut.

 

After all this, clutch pedal still had binding issues after driving it around for a few miles. I took it to the shop that rebuilt/replaced my trans/clutch and the owner said something's not right. He removed the transmission/clutch assembly and saw immediately that the brand new throw-out bearing failed. Somehow it shifted on the input shaft and was causing all kinds of trouble. Replaced and re-installed all under the shop owner's warranty.