CiCiC3

I just had my clutch and flywheel replaced on my '74 and have about 50 miles on it when it starts vibrating very noticeably at high rpm. The speed of the vibration is in sync with the rpm. I have an idea of what's happening but what I don't know is if it is ok to drive it around like that very much. I just need to drive it back to the shop about 5 miles away. Sounds like it needs to be adjusted somehow?

63mako

They probably just bolted it in. Flywheel should be neutral balanced but I have seen them off quite a bit out of the box. Pull it back out and check the balance. Flywheel bolts should be torqued. Pressure plate can be balanced with the flywheel also and those bolts should be torqued as well.

Darinm

Totally agree with this comment. I just brought my BRAND NEW flywheel and pressure plate in to my machine shop to have balanced with crank. The new flywheel was out of balance, and the pressure plate had weight added to it. Once completed, he marked both the flywheel and pressure plate with punch marks so when i reinstall it, i align them up to keep the balance.

jnb5101

They did use an externally balanced flywheel on your 454, didn't they?

CiCiC3

Now I remember doing that last time I did it myself years ago. I would guess they did not and just slapped it in after getting the parts since I didn't request it. I would imagine this is going to cost close to the same price as I just paid to do all this again. May want to do this myself this time possibly. hmmm...thanks for all the info!

larrywalk

Check your pedal freeplay. As rpm increases, the freeplay will decrease slightly. As a test, increase freeplay a turn or so, and then retest to high rpm.

63mako

Sorry, did not realize you had a big block.

cv67

Why would you resign to paying twice bring it back and make them do it right you already paid for it! Dont accept any excuses, shops are full of them.

63mako

CiCiC3

The out of balance theory is fine but why would the vibration not show up until now? I played dragster through 3 gears yesterday and it wasn't until after that the vibration showed up. Did I possibly break the throw-out bearing release spring? This is a big block. The mechanic doesn't think the balancing is the problem.

JoeMinnesota

Is the vibration through the clutch, or felt through the shifter and entire car? If you hammered on it a bit it could be something else now, as a result of having that better clutch. I had a vibration that built with rpm in the past (gen 1 Camaro, not the Vette) show up and Finally found I had sprung/bent the rear yolk at the front of the rear end after a fresh clutch and lots of hard launches.

pauldana

did you use a center force clutch? those weights on them SUCK, and will always give you vibration.

Big2Bird

Worthless

63mako

I have a Centerforce Dual Friction in my 63 with absolutely zero issues. I love it.

DUB

. I am waiting for an answer to what I asked above.

DUB

ddawson

He did already. Too soon to be playing drag racer.

cv67

Wait if I understand this right you were romping (playing drag racer) on it THEN it started vibrating?


If so pull the valve covers pull your pushrods out see if any are bent or broken. Does it idle funny?

CF clutches.....if the motor is broken it can happen never seen one do it when everything is right. Not saying it cant happen but-
personally love them, great pedal feel smooth not muc pedal effort. Mines over 15 yrs old been on 3 motors

sgt kohler

I have a 350 4 speed and all of a sudden started getting vibration. turns out the original rear transmission mount broke. changed it out and all is good

CiCiC3

No not anything to do with the engine. It idles fine. Like I say I have it in the shop now trying to repair the in key ignition switch on the column after just having a totally new install on that. It took about 2 wks for that to go from working like new to gradually not working at all. Then it's back to the other shop to have the clutch re-examined after repairing that. Maybe by Xmas we'll be rolling again.

MotorHead

Did you pay any of these repairs by credit card ?