[C1] Second new clutch kit and still have chatter
08-30-2018, 09:00 AM
#21
Le Mans Master
Member Since: Jul 2018
Location: San Antonio, TX/Mahopac, NY
Posts: 8,380
Received 5,554 Likes
on
2,797 Posts
2024 Corvette of the Year Finalist - Modified
2024 Corvette of the Year Finalist - Unmodified
2023 C7 of the Year Winner - Modified
I talked to McCleod yesterday about their Clutch set and he just said that their is a break-in period of 500 to 750 miles . So I guess I just have to jerk and hop down the road for the next couple summers . This can't be the answer . I have never seen this with a new clutch !
08-30-2018, 12:47 PM
#22
Burning Brakes
Member Since: Aug 2013
Location: palm springs ca
Posts: 1,063
Likes: 0
Received 314 Likes
on
178 Posts
I think you got some good advice here especially about the pilot bushing.
DOM
PS, I also take acetone or similar (one that will dry quickly) and wipe all oily finger prints off the disc, plate, and fly wheel.
DOM
PS, I also take acetone or similar (one that will dry quickly) and wipe all oily finger prints off the disc, plate, and fly wheel.
08-30-2018, 04:13 PM
#23
Race Director
I keep overlooking that this is the second clutch kit with the same results - chatter. I don't think it's the clutch. The odds of getting two bad kits with the same bad behavior is too great. And a clutch may have a little more engagement distance until the fuzzies are worn off the disc and and maybe a bit of very slight shudder if slipping it - but you should not expect the problems you are having as part of break-in.
Last edited by DansYellow66; 08-30-2018 at 04:14 PM.
08-30-2018, 08:32 PM
#24
Le Mans Master
Thread Starter
You and me both! That answer would cause me to rethink McCleod. Yes, some engagement chatter is common prior to break in, but not once the clutch is fully engaged. Your issue sounds like misalignment. Why did you change the clutch to begin with? Was the clutch slipping or did this problem exist with the old clutch?
08-30-2018, 08:37 PM
#25
Le Mans Master
Thread Starter
08-30-2018, 08:44 PM
#26
Le Mans Master
Thread Starter
I keep overlooking that this is the second clutch kit with the same results - chatter. I don't think it's the clutch. The odds of getting two bad kits with the same bad behavior is too great. And a clutch may have a little more engagement distance until the fuzzies are worn off the disc and and maybe a bit of very slight shudder if slipping it - but you should not expect the problems you are having as part of break-in.
08-30-2018, 10:00 PM
#27
Are you torquing down clutch evenly? Failure to do so may cause distortion of the stamped steel cover of the clutch resulting in uneven clamping of the pressure plate, and contributes to a chatter condition.
08-30-2018, 10:23 PM
#28
Le Mans Master
Thread Starter
08-31-2018, 08:45 AM
#29
Safety Car
Member Since: Mar 2006
Location: Itasca IL
Posts: 3,840
Received 849 Likes
on
475 Posts
2015 C2 of Year Finalist
I had one a few years ago that would just about break your teeth out on engagement with two different clutches in it. I finally discovered that one of the pressure plate mounting holes in the flywheel had not been counter-bored sufficiently to accept the alignment shank portion of the corresponding bolt. When it was torqued down, there remained a very small air gap between the housing of the pressure plate and the flywheel surface. It was on the order of 0.020", very hard to notice on visual inspection. It almost drove me insane troubleshooting that problem.
08-31-2018, 11:05 PM
#31
Le Mans Master
Thread Starter
I had one a few years ago that would just about break your teeth out on engagement with two different clutches in it. I finally discovered that one of the pressure plate mounting holes in the flywheel had not been counter-bored sufficiently to accept the alignment shank portion of the corresponding bolt. When it was torqued down, there remained a very small air gap between the housing of the pressure plate and the flywheel surface. It was on the order of 0.020", very hard to notice on visual inspection. It almost drove me insane troubleshooting that problem.
08-31-2018, 11:07 PM
#32
Le Mans Master
Thread Starter
09-01-2018, 07:47 AM
#34
Le Mans Master
Thread Starter
That's where I am planning to go next . Took it out to a cruise last night and it was shaking violently when trying to start out slow . This week I am taking the flywheel out, bolting the clutch set "pressure plate and disc " to the flywheel and taking the whole unit to the machine shop to have it gone over . ( Balanced and trued ) Will report back when that is done . It's a shame that the quality of new parts are so bad when you pay the higher price for what is supposed to be quality parts .
09-02-2018, 07:56 AM
#35
Le Mans Master
Thread Starter
I am still looking at the new flywheel being the problem . This morning I found some more information on " CAUSES OF CLUTCH CHATTER OR SHUDDER " which convinced me that it has to go to the machine shop to be checked . No.# 1 Flywheel or clutch friction surface not parallel with the crank flange surface . And No.#2 Flywheel has an improper step or cup dimension . I found this information on an automotive blog powered by Summit Racing called " ON ALL CYLINDERS " By the way this new flywheel was bought at Summit .
09-02-2018, 11:05 AM
#36
Instructor
I owned a clutch rebuilding shop for 30 years and found many odd problems that caused clutch chatter that you would never think of. Some of the common ones are listed in no particular order. Just some things to check.
1. No marcel in the clutch tabs. The tabs are actually wave springs. This creates the small gap between the 2 clutch facings. You want apx. .020-.030" gap.
2. Incorrect pressure plate bolts. Make sure the shoulder on the bolts are not bottoming out in the flywheel before it tightens the pressure plate down. Check each hole and each bolt.
3. Uneven diaphragm fingers or levers. Fingers should be within .005" of each other. Diaphragm fingers can be about .015" off. Thats how we set them before going to a customer.
4. Incorrectly installed TO bearing.
5. Bent clutch disk. If you had trouble stabbing the trans, you can easily bend the disk. Put it on the input shaft or a spindle and check for runout. Max is apx. .020". Easily straightened by hand.
6. Hot spots on the flywheel or pressure plate.
7. Cracked bell housing.
8. Bad pilot bearing. I reccommend using a bushing. Seen too many bearings ruin an input shaft.
9. Transmission tail shaft bushing worn.
10. Excessive crankshaft endplay. I found this in a customers truck.
11. Bad or 'mushy' motor mounts or transmission mounts.
12. Rear spring shackle bushings or weak spring leaves. Mustangs were really bad about this.
13. Excessive play in ring gear & pinion. Actually found this on a customers car. Fixed the rear end and the chatter went away.
14. Grease or oil on the clutch. (Dirty hands). Chatters when cold, slips when hot.
15. Clutch facing material. Some brands of facings are more prone to chatter than others. The old obsolete asbestos facings were the best, but none have been available for years. Metallic facings will chatter.
16. Worn input shaft - both the splines and the pilot surface.
17. Worn trans quill. Thats the front bearing retainer that the TO bearing slides on. Found one where the quill had broken off and was missing.
18. Make sure the spring that holds the fork to the ball is keeping it in place. And that the pivot in the fork and the ball are not worn.
19. Tighten down the pressure plate bolts evenly in a crisscross pattern a little at a time.
These are some of the most common causes. Couldn't think of much more. I've been retired too long.
1. No marcel in the clutch tabs. The tabs are actually wave springs. This creates the small gap between the 2 clutch facings. You want apx. .020-.030" gap.
2. Incorrect pressure plate bolts. Make sure the shoulder on the bolts are not bottoming out in the flywheel before it tightens the pressure plate down. Check each hole and each bolt.
3. Uneven diaphragm fingers or levers. Fingers should be within .005" of each other. Diaphragm fingers can be about .015" off. Thats how we set them before going to a customer.
4. Incorrectly installed TO bearing.
5. Bent clutch disk. If you had trouble stabbing the trans, you can easily bend the disk. Put it on the input shaft or a spindle and check for runout. Max is apx. .020". Easily straightened by hand.
6. Hot spots on the flywheel or pressure plate.
7. Cracked bell housing.
8. Bad pilot bearing. I reccommend using a bushing. Seen too many bearings ruin an input shaft.
9. Transmission tail shaft bushing worn.
10. Excessive crankshaft endplay. I found this in a customers truck.
11. Bad or 'mushy' motor mounts or transmission mounts.
12. Rear spring shackle bushings or weak spring leaves. Mustangs were really bad about this.
13. Excessive play in ring gear & pinion. Actually found this on a customers car. Fixed the rear end and the chatter went away.
14. Grease or oil on the clutch. (Dirty hands). Chatters when cold, slips when hot.
15. Clutch facing material. Some brands of facings are more prone to chatter than others. The old obsolete asbestos facings were the best, but none have been available for years. Metallic facings will chatter.
16. Worn input shaft - both the splines and the pilot surface.
17. Worn trans quill. Thats the front bearing retainer that the TO bearing slides on. Found one where the quill had broken off and was missing.
18. Make sure the spring that holds the fork to the ball is keeping it in place. And that the pivot in the fork and the ball are not worn.
19. Tighten down the pressure plate bolts evenly in a crisscross pattern a little at a time.
These are some of the most common causes. Couldn't think of much more. I've been retired too long.
Last edited by ref772; 09-02-2018 at 11:07 AM.
The following 4 users liked this post by ref772:
09-02-2018, 10:41 PM
#37
Le Mans Master
Thread Starter
I owned a clutch rebuilding shop for 30 years and found many odd problems that caused clutch chatter that you would never think of. Some of the common ones are listed in no particular order. Just some things to check.
1. No marcel in the clutch tabs. The tabs are actually wave springs. This creates the small gap between the 2 clutch facings. You want apx. .020-.030" gap.
2. Incorrect pressure plate bolts. Make sure the shoulder on the bolts are not bottoming out in the flywheel before it tightens the pressure plate down. Check each hole and each bolt.
3. Uneven diaphragm fingers or levers. Fingers should be within .005" of each other. Diaphragm fingers can be about .015" off. Thats how we set them before going to a customer.
4. Incorrectly installed TO bearing.
5. Bent clutch disk. If you had trouble stabbing the trans, you can easily bend the disk. Put it on the input shaft or a spindle and check for runout. Max is apx. .020". Easily straightened by hand.
6. Hot spots on the flywheel or pressure plate.
7. Cracked bell housing.
8. Bad pilot bearing. I reccommend using a bushing. Seen too many bearings ruin an input shaft.
9. Transmission tail shaft bushing worn.
10. Excessive crankshaft endplay. I found this in a customers truck.
11. Bad or 'mushy' motor mounts or transmission mounts.
12. Rear spring shackle bushings or weak spring leaves. Mustangs were really bad about this.
13. Excessive play in ring gear & pinion. Actually found this on a customers car. Fixed the rear end and the chatter went away.
14. Grease or oil on the clutch. (Dirty hands). Chatters when cold, slips when hot.
15. Clutch facing material. Some brands of facings are more prone to chatter than others. The old obsolete asbestos facings were the best, but none have been available for years. Metallic facings will chatter.
16. Worn input shaft - both the splines and the pilot surface.
17. Worn trans quill. Thats the front bearing retainer that the TO bearing slides on. Found one where the quill had broken off and was missing.
18. Make sure the spring that holds the fork to the ball is keeping it in place. And that the pivot in the fork and the ball are not worn.
19. Tighten down the pressure plate bolts evenly in a crisscross pattern a little at a time.
These are some of the most common causes. Couldn't think of much more. I've been retired too long.
1. No marcel in the clutch tabs. The tabs are actually wave springs. This creates the small gap between the 2 clutch facings. You want apx. .020-.030" gap.
2. Incorrect pressure plate bolts. Make sure the shoulder on the bolts are not bottoming out in the flywheel before it tightens the pressure plate down. Check each hole and each bolt.
3. Uneven diaphragm fingers or levers. Fingers should be within .005" of each other. Diaphragm fingers can be about .015" off. Thats how we set them before going to a customer.
4. Incorrectly installed TO bearing.
5. Bent clutch disk. If you had trouble stabbing the trans, you can easily bend the disk. Put it on the input shaft or a spindle and check for runout. Max is apx. .020". Easily straightened by hand.
6. Hot spots on the flywheel or pressure plate.
7. Cracked bell housing.
8. Bad pilot bearing. I reccommend using a bushing. Seen too many bearings ruin an input shaft.
9. Transmission tail shaft bushing worn.
10. Excessive crankshaft endplay. I found this in a customers truck.
11. Bad or 'mushy' motor mounts or transmission mounts.
12. Rear spring shackle bushings or weak spring leaves. Mustangs were really bad about this.
13. Excessive play in ring gear & pinion. Actually found this on a customers car. Fixed the rear end and the chatter went away.
14. Grease or oil on the clutch. (Dirty hands). Chatters when cold, slips when hot.
15. Clutch facing material. Some brands of facings are more prone to chatter than others. The old obsolete asbestos facings were the best, but none have been available for years. Metallic facings will chatter.
16. Worn input shaft - both the splines and the pilot surface.
17. Worn trans quill. Thats the front bearing retainer that the TO bearing slides on. Found one where the quill had broken off and was missing.
18. Make sure the spring that holds the fork to the ball is keeping it in place. And that the pivot in the fork and the ball are not worn.
19. Tighten down the pressure plate bolts evenly in a crisscross pattern a little at a time.
These are some of the most common causes. Couldn't think of much more. I've been retired too long.
09-03-2018, 09:15 AM
#39
Race Director
Yes , I have. About 25 years ago I bought a new Hays 30 ib flywheel that was warped and the run out was crazy on it. I had bought it some months before so returning it would be difficult, so I took it to a nearby machine shop to have it surfaced. Unfortunately, they ground it dry and when I came back later to pick it up it was still blisteringly hot and we had to use rags to pick it up. It was still warped - not surprising so I went and got my money back and took it to another shop and they wet blanchard ground it and that flattened it out and it worked fine after that.
Last edited by DansYellow66; 09-03-2018 at 02:27 PM. Reason: mistakenly put down 25 lb flywheel - damn sinus infection
The following users liked this post:
bj1k (09-03-2018)
The following users liked this post:
bj1k (09-03-2018)