Throwout Bearing?

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   Just wanted to update this thread since I had so much great feedback and suggestions on my problem.

Turns out it was the pilot bushing and release bearing. The fellow that repaired it for me thinks the clutch was adjusted up too tight causing the bearing to engage all the time. Guess I should have checked the adjustment when I first got the car. Also found that the transmission mount was shot. The rubber was broken up so bad it basically was dropped to the bottom. I kind of wonder myself if this might have been more the cause of the other failures?? I know the transmission is firmly attached to the bell housing and to the engine but without tail support it must have but some force on the shaft / bushing? Any rate I'm back running in time for the cruise season.  Thanks for all the help!

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Bandana Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Jul/26/2016 Location: NC Status: Offline Points: 473	Post Options Post Reply Quote Bandana Report Post Thanks(0) Quote Reply Topic: Throwout Bearing? Posted: Apr/05/2018 at 9:29am
	Just wanted to update this thread since I had so much great feedback and suggestions on my problem. Turns out it was the pilot bushing and release bearing. The fellow that repaired it for me thinks the clutch was adjusted up too tight causing the bearing to engage all the time. Guess I should have checked the adjustment when I first got the car. Also found that the transmission mount was shot. The rubber was broken up so bad it basically was dropped to the bottom. I kind of wonder myself if this might have been more the cause of the other failures?? I know the transmission is firmly attached to the bell housing and to the engine but without tail support it must have but some force on the shaft / bushing? Any rate I'm back running in time for the cruise season. Thanks for all the help!

1970390amx Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/11/2008 Location: colorado Status: Offline Points: 3314	Post Options Post Reply Quote 1970390amx Report Post Thanks(0) Quote Reply Posted: Sep/25/2017 at 1:58pm
	The tip of the input shaft is supported by the pilot bushing. If it is worn the input can chatter around the inside of the bushing. This chatter is what you hear. The bushing is supposed to be self lubricating but lots of them are dried out. I set them on my finger tip and fill the inside with oil and cover with another finger and press, you can see the oil wick through them. Then install.
	1970 390 4speed Bittersweet shadow mask AMX 1970 Amx missing most everything, or in a box

Bandana Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Jul/26/2016 Location: NC Status: Offline Points: 473	Post Options Post Reply Quote Bandana Report Post Thanks(0) Quote Reply Posted: Sep/24/2017 at 10:11am
	While I'm hoping the cause of this problem will come to light when the transmission finally gets pulled and components are inspected, I have to ask you guys, if either the throw out bearing or pilot bushing are bad, what would cause the grinding noise? Why would it seemingly be gone and then return?

Javelin69 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Dec/11/2013 Location: Madison wi Status: Offline Points: 187	Post Options Post Reply Quote Javelin69 Report Post Thanks(0) Quote Reply Posted: Sep/23/2017 at 11:07pm
	I'm with AMX. Sounds like a pilot bushing to me.

Bandana Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Jul/26/2016 Location: NC Status: Offline Points: 473	Post Options Post Reply Quote Bandana Report Post Thanks(0) Quote Reply Posted: Sep/23/2017 at 7:19pm
	Got home last night after a week away. My rebuilt starter was in the parcel box when I got back so I spent the evening in the garage putting it in. This morning I tried her out first moving back and forth in the garage - all good , no grinding noise. Moved out to the driveway and some longer forward and back - still all good.. I'm getting pleased but still can't think how the starter figures in to the grinding noise. Got brave and took a drive out to a local car show about 15 miles away - did good all the way out, no noise. Got ready to leave after a few hours and the damn grinding started again as I was trying to leave the show - albeit not as loud as the previous episode. Once I got on the highway it didn't do it again until I was pulling into my garage.... Looks like the transmission is going to have to come out after all.......

1970390amx Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/11/2008 Location: colorado Status: Offline Points: 3314	Post Options Post Reply Quote 1970390amx Report Post Thanks(0) Quote Reply Posted: Sep/16/2017 at 12:17am
	More often than not a throw out bearing will always make noise when you put your foot on the clutch. When you put the trans into gear and start to take your foot off the clutch you are bringing the input shaft to the same speed as the crank shaft. This causes a lot of stress on the pilot bushing. Said bushing is made out of oil impregnated brass. They dry out and wear severely and make terrible noise as you release the clutch.
	1970 390 4speed Bittersweet shadow mask AMX 1970 Amx missing most everything, or in a box

Bandana Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Jul/26/2016 Location: NC Status: Offline Points: 473	Post Options Post Reply Quote Bandana Report Post Thanks(0) Quote Reply Posted: Sep/15/2017 at 7:27pm
	First step of this repair initiated. Powermaster is taking the starter back for rebuild. They will only charge parts and will do an autopsy to see how it failed. Fellow I spoke to thought the grinding noise may have been coming from the starter - more wishful thinking !! Hopefully I'll hear back from them by the time I get home next weekend..

Bandana Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Jul/26/2016 Location: NC Status: Offline Points: 473	Post Options Post Reply Quote Bandana Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 9:08pm
	Will do but it may take some time to get it done. I'm not having any luck finding someone local to do the work so I may have to tackle it myself (would be a first for me!). I'm going to get a starter on order this week. Next week I am gone all week so it'll be another week before I can start on it. Man I wish I had a lift.....

mmaher94087 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Apr/01/2008 Location: Arizona Status: Offline Points: 1690	Post Options Post Reply Quote mmaher94087 Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 8:46pm
	"..the loud grinding noise.". That is what is bothering me. The noise you described is clutch related from your description, unless something from the starter fell into the bellhousing. The noise, as you described it, only happened when the clutch pedal was depressed and released (allowed to return to its normal position). If the noise was during the time that you depressed the pedal and released it; then I can only think of the T/O bearing. Please tell us what you discover.
	Mike

Bandana Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Jul/26/2016 Location: NC Status: Offline Points: 473	Post Options Post Reply Quote Bandana Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 7:59pm
	You're right that the starter definitely needs to be replaced. Just hope that there is not something in the clutch assembly that caused it to break? Damn thing runs over $200. Before I found the starter problem I had started it up a few times without issue and rolled forward and backward in gear to try and get it to make the loud grinding noise. Took several tries before it did it and it was the same as over the weekend. As soon as the grinding noise started I pushed the clutch back in and it took a good 10 seconds for the grinding to stop. I also noted that I could vaguely hear (between the exhaust note and my bad hearing) a sound difference when the clutch was depressed and when it was out. May always have been there and I was just listening closely this time. It wasn't loud but it was there.