Clutch Problems
Thread Starter
Pro
Joined: Mar 2001
Posts: 587
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From: Leonard, MI USA
Clutch Problems
I have a 1967 327/350 hp car with Muncie 4 speed.
I have searched the forums for over an hour and can't seem to find a solution, so I am posting this.
Today while driving it, the clutch seems to be acting up.
Symptoms:
1. While cruising at 65mph or so in 4th gear, if you hit the throttle wide open, the revs climb 500-600 rpm before the car seems to accelerate. Kind of a slipping feeling.
2. The car is difficult to get into 1st gear/downshift when coming to a stop.
3. The clutch seems to have a slipping feeling while accelerating.
Questions:
1. Is this an adjustment issue
OR
2. Is the clutch worn out - needs replacement
If it is an adjustment issue, can someone help me on how to adjust - basic step by step.
if I need a new clutch, can someone point in the right direction as to which one to buy, install instructions, adjustment instructions, etc.
Any and all help is greatly appreciated.
Thank you.
UPDATED: when going about 20-25 mph, and mash the throttle - the revs don't climb. The car lugs along. Also, with the tires blocked, and the car in fourth gear, giving it gas and slowly letting out the clutch the revs don't climb either, the car starts to move forward slowly and will stall.
I have searched the forums for over an hour and can't seem to find a solution, so I am posting this.
Today while driving it, the clutch seems to be acting up.
Symptoms:
1. While cruising at 65mph or so in 4th gear, if you hit the throttle wide open, the revs climb 500-600 rpm before the car seems to accelerate. Kind of a slipping feeling.
2. The car is difficult to get into 1st gear/downshift when coming to a stop.
3. The clutch seems to have a slipping feeling while accelerating.
Questions:
1. Is this an adjustment issue
OR
2. Is the clutch worn out - needs replacement
If it is an adjustment issue, can someone help me on how to adjust - basic step by step.
if I need a new clutch, can someone point in the right direction as to which one to buy, install instructions, adjustment instructions, etc.
Any and all help is greatly appreciated.
Thank you.
UPDATED: when going about 20-25 mph, and mash the throttle - the revs don't climb. The car lugs along. Also, with the tires blocked, and the car in fourth gear, giving it gas and slowly letting out the clutch the revs don't climb either, the car starts to move forward slowly and will stall.
Last edited by kyosho; Nov 5, 2008 at 11:22 PM.
Thread Starter
Pro
Joined: Mar 2001
Posts: 587
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From: Leonard, MI USA
Burning Brakes
Joined: Jun 2008
Posts: 1,194
Likes: 13
From: Seattle area, WA (On the Eastside)
Try adjusting the clutch rod coming out of the firewall first. Screw the nuts counterclockwise so that they rotate towards the front of the car. I don't know how much you may need...try an inch to start. From what I've seen, folks will have that outer nut all the way to the end of the clutch rod before deciding to replace the clutch. Mine still has over an inche left to play with. Hope this helps, and I think your dilemma is important for safety reasons...you need to get out of the way of an errant driver and the clutch slips. Not good!
Sorry about the picture...too much coffee I guess! This is before I adjusted the swivel about an inch forward. I think you can still see it.
Sorry about the picture...too much coffee I guess! This is before I adjusted the swivel about an inch forward. I think you can still see it.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Try adjusting the clutch rod coming out of the firewall first. Screw the nuts counterclockwise so that they rotate towards the front of the car. I don't know how much you may need...try an inch to start. From what I've seen, folks will have that outer nut all the way to the end of the clutch rod before deciding to replace the clutch. Mine still has over an inche left to play with. Hope this helps, and I think your dilemma is important for safety reasons...you need to get out of the way of an errant driver and the clutch slips. Not good!
Sorry about the picture...too much coffee I guess! This is before I adjusted the swivel about an inch forward. I think you can still see it.
Sorry about the picture...too much coffee I guess! This is before I adjusted the swivel about an inch forward. I think you can still see it.
I am commenting only to prevent some confusion here. First Astroduck's clutch adjustment rod isn't typical of a correct clutch adjustment. The nuts on his linkage are run all the way aft on the upper rod. Typical of a clutch adjustment using factory correct parts and an unworn clutch would have the adjustment nuts all the way forward, not aft.
If you want free play on the clutch pedal, adjust the nuts so the swivel moves AFT on the upper rod to increase free play. A couple rounds on the nuts will get you a lot more than that at the clutch pedal.
Burning Brakes
Joined: Jun 2008
Posts: 1,194
Likes: 13
From: Seattle area, WA (On the Eastside)
I thought that's what I said 
Now I'm really confused.
From what I've seen, folks will have that outer nut all the way to the end of the clutch rod before deciding to replace the clutch.
That picture was taken "BEFORE" I moved the nuts/swivel from 'aft' to about halfway forward into the threaded area. As folks adjust the clutch over time, that swivel gets placed more and more close to the end of the rod. I guess I should have taken a photo of mine in it's current position rather than before. I believe this shot was taken before the rod was attached to the pedal as a means of just storing it in place. I had to purchase a new rebuild kit for the clutch cross shaft and that's where these pics came from. Sorry for the confusion if there was any.
Now I'm really confused. From what I've seen, folks will have that outer nut all the way to the end of the clutch rod before deciding to replace the clutch.
That picture was taken "BEFORE" I moved the nuts/swivel from 'aft' to about halfway forward into the threaded area. As folks adjust the clutch over time, that swivel gets placed more and more close to the end of the rod. I guess I should have taken a photo of mine in it's current position rather than before. I believe this shot was taken before the rod was attached to the pedal as a means of just storing it in place. I had to purchase a new rebuild kit for the clutch cross shaft and that's where these pics came from. Sorry for the confusion if there was any.
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Brett Foote
Instructor
Joined: Apr 2008
Posts: 100
Likes: 6
From: Sonora CA
If after you get your pedal freeplay, as others have indicated
and you still have the slipping, or the clutch grabs high on the pedal, you ought to be thinking about putting in a new clutch.
I just had a Luk clutch kit put in my 67 327/300HP in the OEM type and size, and I am very happy with it. Would advise to go the OEM type and size, as you might have some linkage problems with some of these newer performance type clutches.
At the same time take a look a your linkage for worn, deteriorated parts to replace, maybe a new clutch boot.
As far as installation, see the 67 service manual. Since I don't have the guts and facilities to drop the transmission, I took mine to the same mechanic who did the old clutch 16 years ago. Geez, a 3:08 rear end is tough on clutches.
and you still have the slipping, or the clutch grabs high on the pedal, you ought to be thinking about putting in a new clutch.
I just had a Luk clutch kit put in my 67 327/300HP in the OEM type and size, and I am very happy with it. Would advise to go the OEM type and size, as you might have some linkage problems with some of these newer performance type clutches.
At the same time take a look a your linkage for worn, deteriorated parts to replace, maybe a new clutch boot.
As far as installation, see the 67 service manual. Since I don't have the guts and facilities to drop the transmission, I took mine to the same mechanic who did the old clutch 16 years ago. Geez, a 3:08 rear end is tough on clutches.
Thread Starter
Pro
Joined: Mar 2001
Posts: 587
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From: Leonard, MI USA
Thanks for the responses - the nuts on my linkage are near the end at the front of the car, about 3/8" from the end if this helps. So are you saying I should start by running the nuts towards the rear of the car?
Burning Brakes
Joined: Jun 2008
Posts: 1,194
Likes: 13
From: Seattle area, WA (On the Eastside)
I don't think so, but then I know nothing about free play of pedal. It seems that you are at the end of your adjustability and may need a new clutch. As I said before, the clutch engages better when the adjustment swivel goes towards the front of the car. You have no more thread to go forward much.
Thread Starter
Pro
Joined: Mar 2001
Posts: 587
Likes: 0
From: Leonard, MI USA
I don't think so, but then I know nothing about free play of pedal. It seems that you are at the end of your adjustability and may need a new clutch. As I said before, the clutch engages better when the adjustment swivel goes towards the front of the car. You have no more thread to go forward much.
: Ugh. Ok, if that is the case, anyone here that can point me in the right direction as to the parts list and a decent write up on hwo to change it?And again, thanks for the help.
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
[QUOTE=kyosho
the nuts on my linkage are near the end at the front of the car, about 3/8" from the end if this helps. So are you saying I should start by running the nuts towards the rear of the car?[/QUOTE]
Yes. Run the nuts aft on the upper adjustment rod aft a couple of rounds. That'll give you more freeplay at the pedal.
Can you spin the tires from a dead stop? Difficult to get in first when coming to a stop? What about standing still and go to reverse? Does it grind? If it grinds going into reverse standing still and seems to slip in the forward gears, you probably need a new clutch.
the nuts on my linkage are near the end at the front of the car, about 3/8" from the end if this helps. So are you saying I should start by running the nuts towards the rear of the car?[/QUOTE]
Yes. Run the nuts aft on the upper adjustment rod aft a couple of rounds. That'll give you more freeplay at the pedal.
Can you spin the tires from a dead stop? Difficult to get in first when coming to a stop? What about standing still and go to reverse? Does it grind? If it grinds going into reverse standing still and seems to slip in the forward gears, you probably need a new clutch.
Thread Starter
Pro
Joined: Mar 2001
Posts: 587
Likes: 0
From: Leonard, MI USA
Yes, the car will spin the tires from a stop. Yes, difficult into 1st gear. Will shift into reverse easily it seems - no grinding. Yes, I seem to feel slipping at some times and vibration at some times. Could oil/contaminants getting into the bellhousing cause this?
All the 'normal' tests - 20-25 mph in 4th gear, mash the throttle, no revs climbing. Chock the wheels, put it in 4th gear, let out the clutch while giving it gas - no revs climbing. Seems to mainly happen while cruising at higher speeds - hit the throttle and the revs climb before the car seems to move.
All the 'normal' tests - 20-25 mph in 4th gear, mash the throttle, no revs climbing. Chock the wheels, put it in 4th gear, let out the clutch while giving it gas - no revs climbing. Seems to mainly happen while cruising at higher speeds - hit the throttle and the revs climb before the car seems to move.
Last edited by kyosho; Nov 6, 2008 at 12:00 PM.
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
Yes, the car will spin the tires from a stop. Yes, difficult into 1st gear. Will shift into reverse easily it seems - no grinding. Yes, I seem to feel slipping at some times and vibration at some times. Could oil/contaminants getting into the bellhousing cause this?
All the 'normal' tests - 20-25 mph in 4th gear, mash the throttle, no revs climbing. Chock the wheels, put it in 4th gear, let out the clutch while giving it gas - no revs climbing. Seems to mainly happen while cruising at higher speeds - hit the throttle and the revs climb before the car seems to move.
All the 'normal' tests - 20-25 mph in 4th gear, mash the throttle, no revs climbing. Chock the wheels, put it in 4th gear, let out the clutch while giving it gas - no revs climbing. Seems to mainly happen while cruising at higher speeds - hit the throttle and the revs climb before the car seems to move.
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
Paragon carries the same LuK clutch kit Jerry (gjfeng) put in his car, or an auto parts store should be able to order it for you from their sources, or you can get it from www.dialaclutch.com . The '67 Chevy Chassis Service Manual has the detailed procedure; be sure and have your flywheel resurfaced, and replace the pilot bushing. 
Instructor
Joined: Apr 2008
Posts: 100
Likes: 6
From: Sonora CA
As MikeM says, yes run the nuts toward the back of the car. See if you can get 3/4" -1" freeplay in the pedal. With the freeplay, then do your road tests. If you are still slipping or the clutch grab is high on the pedal, you need a new clutch.
If you are no longer slipping, and the clutch grab is low on the pedal, then it was only the adjustment that solved the problem. If you have no freeplay, then it is possible that the clutch is being held off the flywheel or you have reduced force on the flywheel.
When you replace the clutch, get the flywheel turned. That's why I took mine to a shop. Didn't even have to ask.
If you are no longer slipping, and the clutch grab is low on the pedal, then it was only the adjustment that solved the problem. If you have no freeplay, then it is possible that the clutch is being held off the flywheel or you have reduced force on the flywheel.
When you replace the clutch, get the flywheel turned. That's why I took mine to a shop. Didn't even have to ask.