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New throw out bearing same noise muncie 4

13K views 27 replies 9 participants last post by  rharveysr 
#1 ·
Ok all,

About a month ago started getting this noise/vibration when I pushed in the clutch. Sounded like a briggs/stratton centerfugel clutch whoble that needed some oil on brass bearing. It happends when I press on the clutch paddel and some times when I put it in reverse. You can feel it in the paddel and sound nasty, I replaced the TH/O bearing a few days ago with a good SKF bearing still same noise comes and goes. 11" center force clutch, fork is in good shape. checked the oil in the trans, full, clean, I did find a little bit of metal on the two magnetic plugs I think thats normal. Brass pilot bearing. going down the road there is no problems no noise. Last year when I had the trans out I inspected the gears didn't see any thing that looked odd. Any insite would be thanksfull hate to damage a Muncie.:confused:
 
#3 ·
are you sure it's the throw out bearing and not a flywheel thickness issue ?

is it a stock or E Bay flywheel ? i purchased one where the seller neglected to notify it was for use with a NON-Spung clutch disc... the springs in the disc hit the bolt heads.

if it is the throw out bearing, did you install it correctly ?



 
#4 ·
Yep I see your installation and that is correct as for the fly wheel I have had it out a few times as for hitting of the bolts on the pring's there is no dust of odd sort's in the clutch chamber area no vissual damage. I didn't see any thing that appeared to be cracked not sure what cover you are talking about. All these componets have been in and out several time over the last year. So there has been a differant fork and now new bearing. Is it posiable that there is a problem in the trans?
 
#6 ·
this was my thought too.Id check the pilot bushing in the end of the crank.Bronze is kinda soft so it could be egg shaped ever so slightly and you wouldnt be able to see it.Id replace the bronze bushing with a roller bearing type bushing if it were me.As far as the internals of the trans the only way to really check is to dissassemble it.Like Veno said it could be the input shaft bearing also.Good luck
 
#8 ·
Well the pilot bearing is new if 2,500 miles inspected the trans shaft tip smooth, all the finger looks good all at same level no dis collor or wear. I think the plate you are taliking about is the input shaft support. does it have four bolts with antie loosen retainers on them if so I imspected that looks good. Let me ask this if the bearing is bad can it be replaced via the front cover or from the inside and if the bearing is bad does this require addtional parts that caused its failure or could it have failed by its self and then only need to replace it thanks.
 
#10 ·
The plate is called the bearing retainer. If there are any groves in it, replace it. They are cheap and easy to replace. There should be a small amount of lubricant on the bearing retainer as well. don't put too much or it will get on the clutch.

If the input bearing is bad, you will hear it with the clutch engaged. You will hear a rattle from it as the ball bearing bang against each other. It is easy to check by removing the bearing retainer. You will often get a vibration if the bearing is bad.
 
#11 ·
Plowman are you saying that the bearing is threaded on or a nut holding it on under the cover? I looked at a drawing today it looked as if the Bearing retainer held the bearing in place. tnblkc230WZ that is what is odd it seams to be good going down the road or at least i can't hear it, it is only when I put the car in gear forward or reverse clutch pedal to the floor that I hear the noise. If the noise does accur not always I can ingage the clutch and load the engine slitly some times it will stop it or just take off and it will stop.
 
#14 ·
tnblkc230WZ that is what is odd it seams to be good going down the road or at least i can't hear it, it is only when I put the car in gear forward or reverse clutch pedal to the floor that I hear the noise. If the noise does accur not always I can ingage the clutch and load the engine slitly some times it will stop it or just take off and it will stop.
Put the car in neutral, let the clutch out and listen under the car. You will usually hear the ball bearings rattle if they are bad.
 
#13 · (Edited)
Ok, I just got off of Riverside gear's web page in GR Michigan. I see how it all goes together so additional questions there. Tvnl that is correct the noise seams to only accure when the clutch is pressed to the floor and you put it in gear F or R any gear. So dose this rase any questions requarding the pressure plate or clutch. like I had mentioned the fork is a differant one same style and the pilot bearing is low miles and throw out bearing is new. As mentioned prior in this thread it is looking like I might have an egg shaped pilot bearing that would cause the oscalation of the input shaft at idle and would be turning in drive. Whats every one think :confused:
 
#15 · (Edited)
If your pilot bearing is bad, it WILL vibrate driving down the road. It will eventually destroy the input bearing on the trans as well

The pilot bearing and the input bearing hold the input shaft in perfect alignment. If either are bad, the input shaft will wobble. If this happens, the clutch disk will be allowed to wobble a little too.

The bronze pilot bushings are pretty reliable. If it is bad, I look for other issues that may have caused it to get egg shaped.
 
#17 · (Edited)
Well at this point I will replace the pilot bearing with roller unit and the drive bearing and let every one know what the out come is. Plowman I beleive the clutch is adjusted right, there is a fare amount of pre load on the T/O bearing IE enough to keep the peddal up. When the trans was out I had some one push the peddal in and had plenty of disk movement fronf to rear thanks agian.
 
#18 ·
Take care using a pilot bearing, they are much LESS forgiving when misaligned compared to a bushing. I run a bushing with a BB and M20, with no issues. Sorry I have no advise as to what is causing your problems.

Just a thought, have you checked the new throw out, it could be bad even though it's new? Unlikely, but possible.
 
#19 ·
What do you have to lose,try taking some adjustment out of the clutch see if that changes the noise[cheap and quick try]. About 30thousands of a inch is all that is needed to disconnect. The clutch return spring holds the pedal up,not the clutch adjustment. 30thousands between the clutch disc and flywheel.
 
#20 ·
It's lots easier to pinpoint a problem if you first understand how the system works..... When the car is in gear and the pedal is depressed the input shaft and clutch plate are stationary. The flywheel and pressure plate are spinning at engine RPM. Everything in the trans is sitting still. The only friction points in this state that could make noise are the Pilot bearing/bushing, the T/O bearing or even the clutch plate. Sometimes if the flywheel has been turned down the springs in the clutch plate can even hit the flywheel bolts and make some noise, it will be evidant when you take it apart.

When an input bearing goes bad the best way to hear it is with the car in neutral and the clutch pedal released..... I don't think your problem is in the trans.
 
#21 ·
two year ago I had the fly wheel resurfaced, I do remeber at that time having it happen every now and then it didn't consern me as it was every seldom. Last year I put in a differant T/O bearing with the motor out thinking that was it, Both bearings used. At that time I inspected all parts and found no signs of wear FW bolts, CL plate, FW, PR plate. LIke I had said there is a good amount of pre load on the T/O bearing. So when I press the clutch peddal that would put a longer travel on the P/P fingers. When the noise does accure it is continuse until you release the clutch peddal and start moving. I undreastand that when the clutch is pressed the FW and PP are spinning it is at this point the noise will start. Now if the car is in neutral and making the noise you can let the clutch peddal up and the noise will remain, you have to put some type of load on it for it to go away. I will try to release some of the pre load on the T/B. I agree that the shaft bearing is most unlikely a this point and do aggree with the posiabilty of the T/B new being bad. So lets try this I will replace the pilot bearing with brass unit and T/B and a new clutch plate for good mesure. Has any one ever heard of a clutch plate being warped? could that be rubbing on my FW.
 
#22 · (Edited)
there is no preload on a throw out bearing... to the contrary, it should be adjusted for a .250 clearance bearing to finger. this allows the clutch to grow with heat and usage.

a throw out bearing that's in constant contact with clutch fingers promotes wear on bearing and clutch fingers...


[edit] if when you adjust the bearing for the .250 clearance... test the clutch actuation... if it's not fully disengauging then i'd say you have a clutch pivot/throw out bearing height issue. you might need an adjustable pivot if it won't disengauge with proper clutch adjustment.
 
#24 ·
Flyer and tnblkc230wz you correct there should be no preload on the T/B I do that just for quicker clutch release, personl preferance. You are also right that will add adtional wear to the bearing and finger. I will some time next few days adjsut that to your spec's and see if any thing has changed thanks for the info. Ordered all the parts today looks as if this weekend, if I see any thing odd I will take some photos thanks again.
 
#25 ·
Problem solved, Well thanks all that assited first. What was causing the noise was a worn pilot bearing brass. what I replaced was the pilot bearing, clutch, Bearing retainer, and main shaft bearing and prior to all that the T/B. Talking with a local speed shop, what was happening was the pilot bearing should be about .590 and the one I took out was .638 not allot but enought to cause the main shaft to vibrate when stationarry and crank turning. Keep in mind that it wasn's egg shape but worn in a circal. According to the shop there are two things that can cause this, one the main bearing in the trans bad, two the classic miss aligned bell houseing. both my pins are in the block, from what I understand thay make off set pins if needed. Now that these parts have been replaced if the pilot bearing goes out agian then most likely my bell housing needs to be aligned with the crank. One last thing I took the main bearing to work and check it for side to side and foward and reverse movement, well with in spec's. Thanks again all.:yes:
 
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