throw out bearing orientation
Thread Starter
Burning Brakes
Joined: Apr 2011
Posts: 975
Likes: 108
From: Phoenix, AZ
throw out bearing orientation
While removing my manual transmission (69 350/350), I noticed the throw out bearing missing from the clutch fork. I fished it out of the of the bell housing.
What is the correct orientation for the bearing? Large side facing out of the bell housing toward the rear of the car, or other way around?
Having the transmission looked at by a local shop--symptoms: whines when taking my foot off the gas and it does not appear dependent upon the gear. Acceleration is no problem in 1st through 4th. How difficult it is to rebuild on my own? Removing the transmission was easy--2 out of 5 wrenches and the car was resting on jack stands.
What is the correct orientation for the bearing? Large side facing out of the bell housing toward the rear of the car, or other way around?
Having the transmission looked at by a local shop--symptoms: whines when taking my foot off the gas and it does not appear dependent upon the gear. Acceleration is no problem in 1st through 4th. How difficult it is to rebuild on my own? Removing the transmission was easy--2 out of 5 wrenches and the car was resting on jack stands.
Melting Slicks
Joined: Sep 2007
Posts: 2,149
Likes: 284
From: cary Il
removing the trans is easy, reinstalling and line up evey thing is the hard part, you most likey at this point should install a new clutch,throw out, and piolit bearing, the whine sound could be a bad throw out and pilot bearing, the bearing side of the throw out goes towards the clutch.
Safety Car
Joined: Jun 2013
Posts: 4,399
Likes: 793
clutch
I agree with checking the rest of the clutch parts especially the flywheel. This part is the culprit for many problems. Check for hair line cracks and un even surface which causes a chatter affect. Good luck
Roger
Roger
Thread Starter
Burning Brakes
Joined: Apr 2011
Posts: 975
Likes: 108
From: Phoenix, AZ
flywheel quesitons
Thanks for all of the replies and pic--very helpful and informative. To the point on the origin of the whine, the noise began before I had the rear end professionally rebuilt by Tracdogg, and the whine fluctuates when engaging the clutch. It is now embarrassingly worse--meaning louder.
More questions: flywheel--I don't see any cracks, it is smooth to the touch across the discolored areas. is it necessary to resurface the flywheel from what you see? Also, I read that the pilot bushing should be bronze and the one previously installed here is partly made of iron. I purchased a clutch kit from NAPA and the pilot bushing is bronze. One opinion on the topic of the pilot bushing shared that an iron bushing would cause a whine after a certain period of time. Can anyone else confirm that opinion? Lastly, I don't know what the numbers, 1-10 mean on the inner circle of the flywheel--any help appreciated.
More questions: flywheel--I don't see any cracks, it is smooth to the touch across the discolored areas. is it necessary to resurface the flywheel from what you see? Also, I read that the pilot bushing should be bronze and the one previously installed here is partly made of iron. I purchased a clutch kit from NAPA and the pilot bushing is bronze. One opinion on the topic of the pilot bushing shared that an iron bushing would cause a whine after a certain period of time. Can anyone else confirm that opinion? Lastly, I don't know what the numbers, 1-10 mean on the inner circle of the flywheel--any help appreciated.
Racer
Joined: Dec 2011
Posts: 284
Likes: 4
From: Philadelphia Pennsylvania
When I changed my clutch I used the same NAPA kit w/bearing and didn't have any noise. I did have my flywheel resurfaced, though, which I read was recommended any time you change the clutch. It was only $40 at a nearby machine shop.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
OK, try this:
You can generally replace the flywheel for a few bucks more than resurfacing. Your choice though.
Buy a manual and torque wrench. Use Loctite and follow torque specs and tightening sequence on both flywheel and pressure plate.
Replace both the pilot bearing and throwout bearing. The pilot bearing can be steel, needle bearing type or bronze bushing. If a steel needle bearing dies, it can damage the trans input shaft or crank. A bronze wont do that. Again, your choice.
There's a right and wrong way to install the throwout bearing. And I'm not talking about backwards. It has to be placed on the fork correctly, look it up, plenty of pics/diagrams online. Btw, the pic above is wrong.
As for rebuilding the trans, it's not too hard but still a lot more difficult than changing a clutch. A press and a few more specialty tools are required that I'm guessing you don't have. In that case, let someone else do it.
You can generally replace the flywheel for a few bucks more than resurfacing. Your choice though.
Buy a manual and torque wrench. Use Loctite and follow torque specs and tightening sequence on both flywheel and pressure plate.
Replace both the pilot bearing and throwout bearing. The pilot bearing can be steel, needle bearing type or bronze bushing. If a steel needle bearing dies, it can damage the trans input shaft or crank. A bronze wont do that. Again, your choice.
There's a right and wrong way to install the throwout bearing. And I'm not talking about backwards. It has to be placed on the fork correctly, look it up, plenty of pics/diagrams online. Btw, the pic above is wrong.
As for rebuilding the trans, it's not too hard but still a lot more difficult than changing a clutch. A press and a few more specialty tools are required that I'm guessing you don't have. In that case, let someone else do it.
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Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
I opted NOT to get my flywheel resurfaced 20 years ago when I did a frame off refurbishment. Big mistake, clutch chattered. I am now going through the process of replacing the clutch again. A local machine shop resurfaced the flywheel while I waited, cost $40. Worth doing.
Thread Starter
Burning Brakes
Joined: Apr 2011
Posts: 975
Likes: 108
From: Phoenix, AZ
I opted NOT to get my flywheel resurfaced 20 years ago when I did a frame off refurbishment. Big mistake, clutch chattered. I am now going through the process of replacing the clutch again. A local machine shop resurfaced the flywheel while I waited, cost $40. Worth doing. Only $30 at local transmission shop.
Racer
Joined: Apr 2012
Posts: 257
Likes: 0
OK, try this:
You can generally replace the flywheel for a few bucks more than resurfacing. Your choice though.
Buy a manual and torque wrench. Use Loctite and follow torque specs and tightening sequence on both flywheel and pressure plate.
Replace both the pilot bearing and throwout bearing. The pilot bearing can be steel, needle bearing type or bronze bushing. If a steel needle bearing dies, it can damage the trans input shaft or crank. A bronze wont do that. Again, your choice.
There's a right and wrong way to install the throwout bearing. And I'm not talking about backwards. It has to be placed on the fork correctly, look it up, plenty of pics/diagrams online. Btw, the pic above is wrong.
As for rebuilding the trans, it's not too hard but still a lot more difficult than changing a clutch. A press and a few more specialty tools are required that I'm guessing you don't have. In that case, let someone else do it.
You can generally replace the flywheel for a few bucks more than resurfacing. Your choice though.
Buy a manual and torque wrench. Use Loctite and follow torque specs and tightening sequence on both flywheel and pressure plate.
Replace both the pilot bearing and throwout bearing. The pilot bearing can be steel, needle bearing type or bronze bushing. If a steel needle bearing dies, it can damage the trans input shaft or crank. A bronze wont do that. Again, your choice.
There's a right and wrong way to install the throwout bearing. And I'm not talking about backwards. It has to be placed on the fork correctly, look it up, plenty of pics/diagrams online. Btw, the pic above is wrong.
As for rebuilding the trans, it's not too hard but still a lot more difficult than changing a clutch. A press and a few more specialty tools are required that I'm guessing you don't have. In that case, let someone else do it.
Mike
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
It's pushed on the fork too far.
If you would mount the fork in the bell all the way on the stud, the bearing wont be centered. If you would put pressure on the fork mounted this way, you'll break the rear flange on the bearing.
It should be centered between the fork supports.
If you would mount the fork in the bell all the way on the stud, the bearing wont be centered. If you would put pressure on the fork mounted this way, you'll break the rear flange on the bearing.
It should be centered between the fork supports.
Racer
Joined: Apr 2012
Posts: 257
Likes: 0
It's pushed on the fork too far.
If you would mount the fork in the bell all the way on the stud, the bearing wont be centered. If you would put pressure on the fork mounted this way, you'll break the rear flange on the bearing.
It should be centered between the fork supports.
If you would mount the fork in the bell all the way on the stud, the bearing wont be centered. If you would put pressure on the fork mounted this way, you'll break the rear flange on the bearing.
It should be centered between the fork supports.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
If you put the trans in with it like that, it would more likely pull the fork off the stud.
Also, like stated above, even without putting the trans on, you can break the rear flange of the throwout bearing.
Btw, if you look closely at the bearing in the pic, it almost looks like there's already a crack in the rear flange at the 9:00 position. Hard to tell for sure, but that's where they break when you try to square it up, lodged like that.
Also, like stated above, even without putting the trans on, you can break the rear flange of the throwout bearing.
Btw, if you look closely at the bearing in the pic, it almost looks like there's already a crack in the rear flange at the 9:00 position. Hard to tell for sure, but that's where they break when you try to square it up, lodged like that.
Last edited by Garys 68; Oct 16, 2014 at 10:27 AM.
Thread Starter
Burning Brakes
Joined: Apr 2011
Posts: 975
Likes: 108
From: Phoenix, AZ
pressure plate size, throwout bearing check
Forum--appreciate the help. After two trips to NAPA, believe I made a discovery that this is the wrong flywheel for a 69, L-46. Should it be 14" in diameter? This flywheel's diameter is 12 3/8". Note the correct bolt pattern for the pressure plate, but the edges of the plate extend over the flywheel by a fraction. Is there a concern only if pressure plate interferes with the bell housing?
The diameter of the clutch disc is a hair larger than the one that was removed. I do not see an issue there.
Lastly, can I get a for the throwout bearing orientation and mounting on the clutch fork?
The diameter of the clutch disc is a hair larger than the one that was removed. I do not see an issue there.
Lastly, can I get a
for the throwout bearing orientation and mounting on the clutch fork?
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
I suspect you have a 153 tooth flywheel (SBC) with a 168 tooth clutch (BBC).
Typically the 168 uses the 11" clutch and fits in the 621 bellhousing. And that would be too big to fit in the bellhousing used for the 153 tooth flywheel with 10.4" clutch.
However, I just looked back at your first pic and that looks like a truck bellhousing used with 12" clutch. Does your Muncie have a spacer ring around the front bearing retainer?
Btw, if you change over to the 168 tooth flywheel, you'll probably need a new starter too.
Pic below is a 168 tooth flywheel with an 11" clutch pressure plate.
Typically the 168 uses the 11" clutch and fits in the 621 bellhousing. And that would be too big to fit in the bellhousing used for the 153 tooth flywheel with 10.4" clutch.
However, I just looked back at your first pic and that looks like a truck bellhousing used with 12" clutch. Does your Muncie have a spacer ring around the front bearing retainer?
Btw, if you change over to the 168 tooth flywheel, you'll probably need a new starter too.
Pic below is a 168 tooth flywheel with an 11" clutch pressure plate.
Last edited by Garys 68; Oct 19, 2014 at 08:26 AM.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
It just occurred to me if you're running a truck bellhousing on a car Muncie without the bell to input bearing retainer spacer, your trans wont be aligned correctly. That will result in pilot bearing and the trans input shaft bearing failure. The misalignment of the input shaft gear and countershaft gear will cause a whine and maybe gear damage.
Thread Starter
Burning Brakes
Joined: Apr 2011
Posts: 975
Likes: 108
From: Phoenix, AZ
It just occurred to me if you're running a truck bellhousing on a car Muncie without the bell to input bearing retainer spacer, your trans wont be aligned correctly. That will result in pilot bearing and the trans input shaft bearing failure. The misalignment of the input shaft gear and countershaft gear will cause a whine and maybe gear damage.
Do you have a pic of the correct bellhousing? The clutch and transmission has performed perfectly for the last three years.
Lastly, do you have a picture of the input bearing retainer spacer?
Thanks for the help