Clutch Noise Got Me Stumped

[Jocko_51_B3B]

 

I just installed the clutch and transmission but I get a noise (see the video) when letting out the clutch. Once it's fully let out the noise stops. Here's what has been done:

1. fly wheel has been resurfaced

2. new clutch disc

3. new pilot bearing

4. new pull-back spring on release bearing assembly

5. Surface of release bearing lightly lubed

6. Clutch forks lightly lubed

7. Transmission input shaft lightly lubed.

8. Clutch disc has been installed with the protruding side of the hub pointing back toward the trans (which I believe is correct).

 

More info:

1. I did not replace the release bearing (throw-out bearing) because it rotated freely, seemed well lubed, wasn't loose or sloppy, and I had a professional mechanic give it the OK.

2. The video was made without the driveshaft installed.

3. The video was made in first gear, but it makes the same noise in all gears including neutral.

4. The clutch pedal is adjusted for one inch of free play as per the manual. 

5. I saw nothing obviously wrong with the clutch plate so I installed it without any adjustments, fixes, or modifications.

6. Transmission oil is topped off.

7. Transmission shifts fine between all gears including reverse.

 

If someone else had posted this I would say "Replace the release bearing." but the bearing really looked perfectly good when I inspected it. I'm kind of stumped.

 

 

Edited July 4, 2021 by Jocko_51_B3B

[Tooljunkie]

There is no load on any moving parts in the transmission, i would install driveshaft and take it for a putt. 
the video doesent give us much to work with,a slower motion on pedal may tell us more. I think its just backlash in the gears.

[Dodgeb4ya]

Was the noise why you did the clutch work?

Have you carefully watched the bearing,cross shaft fork and clutch PP cover while someone operates the clutch?

The bearing sleeve sldes smoothly on the lubed trans..... bearing retainer?

It is an odd noise.

[kencombs]

38 minutes ago, Dodgeb4ya said:

Was the noise why you did the clutch work?

Have you carefully watched the bearing,cross shaft fork and clutch PP cover while someone operates the clutch?

The bearing sleeve sldes smoothly on the lubed trans..... bearing retainer?

It is an odd noise.

Really odd!  To my ear is seems perfectly quiet when the pedal is down.  So, not likely to be a TO bearing, as that is when is most stressed..  Then the noise starts when the pedal starts to come up.

 

So, retainer to bearing sleeve grind?  maybe.  A little lube is a cost free test.  I agree with the need to watch while another operates the pedal.  

[Dodgeb4ya]

On the pedal return I was thinking...a long shot for sure...that a slight bind twist on the bearing sleeve because of a new spring or too strong of spring.

There must be a feeling thru the clutch pedal with the noise.

I don't think it's the bearing either...

[Plymouthy Adams]

  would not rule out the fact it may have slipped off the ears of the fork and dragging/scraping on the return that is the pressure plate application only... should be able to inspect this through the fork hole of the bell......but THEN I am not familiar with the truck set up 

[RobertKB]

I had a similar noise in my ‘51. I had the engine rebuilt and the rebuilder kindly said he would install the flywheel and all clutch parts. He had done this hundreds of times before. 
 

Made a bad noise when I engaged the clutch with tranny in. He had installed the clutch disk backward although it clearly stated on the disk which was the flywheel side. Being reversed, the disk springs hit the flywheel bolts. Had to replace the disk. Just a thought. Hopefully you are positive you put your disk the right way around. 

[JBNeal]

That clutch pedal motion is similar to dropping the clutch on a burnout, ya might be hearing the clutch disc and pressure plate springs etc vibrating when the clutch face contacts the flywheel and pressure plate..with all of the new parts, they may not have worn in enough for a smooth engagement.  Hopefully no lube has migrated onto the clutch face, where it can cause problems like shuddering.  Operating the clutch pedal in a slower release similar to when driving might yield a different sound.

[Jocko_51_B3B]

The fact that the noise goes away when the clutch pedal is held down does seem to rule out the release bearing. The noise only happens when I release the pedal about half way as the disk starts to engage. Once fully engaged the noise and vibration disappear. I'm thinking the noise has something to do with the disk or pressure plate. I'll install the driveshaft and see if it makes a difference.

Edited July 5, 2021 by Jocko_51_B3B
better wording

[maddmaxx1949]

To me it sounds like the disk on the flywheel/pressure plate. One I had put together myself from some old parts sounded similar, like sandpaper on a flat metal surface. It still functioned okay but I was just driving the frame around with no body so it didn't have any high torque application really.

[Jocko_51_B3B]

I installed the propeller shaft, but the noise is the same. I'll drive it for a while and see what happens. I don't think driving it will cause damage to anything at this point.

Edited July 5, 2021 by Jocko_51_B3B

[Plymouthy Adams]

34 minutes ago, Jocko_51_B3B said:

I installed the propeller shaft, but the noise is the same. I'll drive it for a while and see what happens. I don't think driving it will cause damage to anything at this point.

 

 

sometimes these are the famous last words......

[P15-D24]

Is the noise coming from the clutch area or pedal area?

[Jocko_51_B3B]

I believe I've found the problem. There is a very slight vibration in the release (throw out) bearing. With the engine running I had a friend operate the clutch pedal as I laid under the truck and watched the release bearing engage and disengage from the pressure plate. I saw a tiny bit of vibration in the bearing itself or between the bearing and the sleeve on which the bearing is mounted. When I depress the clutch pedal all the way down there is so much pressure on the bearing that it prevents it from vibrating. When I take my foot completely off the pedal, the bearing no longer rotates, so the vibration stops. But when I depress the pedal about half way down, as the bearing first begins to spin, there isn't enough force on the bearing to prevent it from vibrating. I'll need to remove the bearing and sleeve assembly to see exactly where the problem exists. If the sleeve diameter is worn down, maybe it's possible to "sleeve the sleeve". Otherwise it's a new bearing. I will post results when I know more.

Edited July 6, 2021 by Jocko_51_B3B

[kencombs]

58 minutes ago, Jocko_51_B3B said:

I believe I've found the problem. There is a very slight vibration in the release (throw out) bearing. With the engine running I had a friend operate the clutch pedal as I laid under the truck and watched the release bearing engage and disengage from the pressure plate. I saw a tiny bit of vibration in the bearing itself or between the bearing and the sleeve on which the bearing is mounted. When I depress the clutch pedal all the way down there is so much pressure on the bearing that it prevents it from vibrating. When I take my foot completely off the pedal, the bearing no longer rotates, so the vibration stops. But when I depress the pedal about half way down, as the bearing first begins to spin, there isn't enough force on the bearing to prevent it from vibrating. I'll need to remove the bearing and sleeve assembly to see exactly where the problem exists. If the sleeve diameter is worn down, maybe it's possible to "sleeve the sleeve". Otherwise it's a new bearing. I will post results when I know more.

That sounds like a classic symtom of the pressure plate release fingers being misadjusted.  The fingers may be at different heights.

[Jocko_51_B3B]

There was nothing apparently wrong with the pressure plate before I installed it, but I will check that possibility and post the results.

Edited July 7, 2021 by Jocko_51_B3B
better wording

[Jocko_51_B3B]

I installed a brand new throw out bearing and put in a NOS bearing sleeve from VPW. Same noise. I think the noise happens on initial contact between the pressure plate, disc, and flywheel. Maybe the noise is accentuated by not having the toe boards in yet. Maybe the new clutch disc and resurfaced flywheel need to "wear in". Maybe this. Maybe that. Who knows. The truck is still on jacks but the clutch seems to be working fine. I don't feel like pulling the pressure plate out right now so I'm going to put things together and drive it for a little while and see what happens next. Here's where the truck stands at the moment...

 

 

 

Edited July 26, 2021 by Jocko_51_B3B

[RobertKB]

I would still make sure and try to eliminate the clutch disc being installed backwards. Been there, done that, as mentioned in a previous post. Engaging the clutch should not be a noisy process. SOMETHING is wrong and if is unlikely to fix itself and go away. 
 

Great looking project by the way!

Edited July 27, 2021 by RobertKB

[Jocko_51_B3B]

The pictures in the parts book show the more protruding side of the disc hub pointing toward the rear of the truck. That's the way I installed it so I believe it is installed correctly. I also had the disc rebuilt. It has all new pads and whatever else they do to it..

Edited July 27, 2021 by Jocko_51_B3B

[dcotant]

Well for what it is worth, I installed the clutch from my 52 parts truck with a 3 speed  (which had been making no noise) into my 49 with a 4 speed. When I first started driving it, there was a strange noise when I let out the clutch at higher rpms (like you would do on a hill). After a few runs and a couple hundred miles it doesn't make that noise anymore. The noise was similar to yours but not quite the same, there was kind of a whine in addition, to me sounded like vibration. This last Saturday I tried to make it make that noise and it did not.

[Merle Coggins]

There was a thread on the forum not too long ago (may have been on the car side) regarding a clutch issue after replacing the clutch disc. It seems that the new disc had a larger center spring hub that interfered with the pressure plate. I don't recall all of the details. But then again, as you eluded to, you may just be hearing 'normal' clutch engagement that you wouldn't normally hear with all of the panels in place.