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Discussion Starter #1
I can shift the car without engine running but as soon as I start the motor its like the clutch is not working at all.
If I shift into 1st gear without motor running and let out the clutch the clutch does not start grabbing until the clutch pedal comes off the floor about 3/4 of the full travel.
This is in my 66 Chevelle. I have had this issue once in a while when stopped at a stop light in nuetral then trying to slip into 1st gear but now it appears to gotten much worse.
I have adjusted the free travel but even with all the travel adjusted out of the clutch there is no change ( still can not shift into gear) If I try for reverse gear it grinds and if I try a foward gear it does not grind but will no way go into gear unless I shut down the engine.
Any ideas?
 

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Sounds like it’s time to pull the trans, pressure plate, clutch and maybe even flywheel to see what is going on. Sounds like something is out of alignment. Perhaps one of those components partially broke. Maybe pilot bearing/bushing failure.
 

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X2 What blm said above ^^
It could be the clutch fork is worn,or the throw out bearing is broken where it rides on the clutch fork or maybe a clutch/pressure plate issue.
Time to pull it !!
Guy
 

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Discussion Starter #4
X2 What blm said above ^^
It could be the clutch fork is worn,or the throw out bearing is broken where it rides on the clutch fork or maybe a clutch/pressure plate issue.
Time to pull it !!
Guy
Arg..... hoping it would be any easy fix
thanks for the reply
 

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Hydraulic throwout bearing. Or mechanical bellcrank? If hydraulic, bleed, and reset the gap.

It's not going into gear because the input shaft is still spinning.
 

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Arg..... hoping it would be any easy fix
thanks for the reply
LOL,In the big picture,this is a relatively easy fix..
Guy
 

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Discussion Starter #7
Hydraulic throwout bearing. Or mechanical bellcrank? If hydraulic, bleed, and reset the gap.

It's not going into gear because the input shaft is still spinning.
.
It is all mechanical linkage , if the input shaft is spinning wouldn’t the gears be grinding when I try to force it into 1st gear?
 

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It grinds in reverse right? Reverse has no synchros. 1st gear has a Syncro to help slow the gears so they match the speed of the shaft, or stop the shaft so it can line up with gears. If the gears don't match speed, you can't shift. That's why you can get into first with the engine off, the input shaft is not spinning.

For some reason, your clutch is not releasing fully. Bent or damaged disk. This can happen if you force the trans to seat by using the bolts to draw in trans or allowing the weight of the trans to hang from the disk before fully inserted. Damaged diaphragm, input bearing/bushing seized or out of alignment, Improper adjustment or not enough throw from the clutch fork. I've seen disks rust to flywheels too.

If this problem was covered up by the Syncro, meaning at one time the Syncro could overcome the rotation of the shaft, the synco might be toast now. The sycro is like a clutch that grabs the gear to speed it up or slow it down to match the speed of the two parts so they can mesh. If the speeds don't align, the syncro acts as a blocker. You don't want to throw a new sycro in, as it will just temporarily cover the real issue which is the spinning input shaft.

What could be the cause for improper clutch release? Improper clutch engagement or disengagement (release) can be the result of any number of problems. Possible causes may be as follows: 1. Release linkage not properly adjusted or reset 2. Flywheel not surfaced before a new clutch installed 3. Flywheel surfaced improperly—incorrect flywheel step or cup dimension 4. Flywheel machined too thin or not manufactured to stock (OEM) specifications. 5. Release linkage worn or damaged 6. Hydraulics defective, leaking or air is trapped in hydraulic system 7. Release linkage cable stretched or damaged 8. Improper clutch fork geometry due to flywheel being too thin or bellhousing deeper than stock 9. Improperly adjusted pivot ball 10.Clutch disc installed improperly (backwards) 11.Clutch disc hitting flywheel bolts 12.Clutch disc binding on transmission input shaft 13.Input shaft bent causing clutch disc runout 14.Pressure plate assembly and/or clutch disc bent or damaged 15.Clutch disc is too thick or has excessive marcel 16.Pressure plate has defective or damaged drive straps 17.Damaged, worn or improperly installed pivot bearing/bushing 18.Damaged or worn throw out bearing collar......Clutch Diagnostics Guide - American Powertrain

So, what to do???
First, adjust out all the play in the clutch rod. Let the throwout bearing ride on the diaphragm fingers. See if it will go into gear. This is just a test for a short term check. It will smoke the throwout bearing if you run the engine for a long period. We're checking to see if your problem is a pivot ball adjustment or linkage set up issue. If this fails, the trans comes out. Some pictures of your clutch fork angle with the fork against the fingers may help me see the issue at this point. We are looking for the 5-7 degree forward angle of the clutch fork.


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One of Jody's old pics.^
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We also want to make sure you are using the correct clutch fork that will give you maximu=m throw with the Chevelle 64-72 bellcrank/Zbar. If you have a Lakewood, HD, or truck type clutch fork, you are losing throw. Note all of these have "wings".
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At this point, it's time to pull the trans.

Will you be doing the work yourself?
 

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I had this issue in a 69 GTO and it was oil on the clutch disc from a leaking distributor.. I pulled it apart and cleaned it with thinner and it worked fine after words. Actually it grabbed a little better then when it was new..
 

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Discussion Starter #13
thanks guys for all the ideas to check. I'll try to get on it this next week
 

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thanks guys for all the ideas to check. I'll try to get on it this next week
Be sure to let us know what you find .
Guy
 

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The only thing that hasn’t been mentioned is bell housing alignment. How long has this transmission been mated to this bell housing and engine? Misalignment SHOULDN’T cause an intermittent problem like you described, but never say never. hopefully whomever installed the transmission took the time to check this.

I agree with the masses that your input shaft is continuing to turn at engine speed. Either clutch or input shaft/pilot bushing problems are where you’re needing to start.
 
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