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Grinding/scraping/noise

Grinding/scraping/noise
C

cjstefan

Jeeper
Posts
28
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Location
Maryland
Vehicle(s)
1984 CJ7
How's it going everyone? Quick background about myself...I got my first CJ (an '86) in 2000. I drove that daily for about 9 years. I replaced it with a TJ, since it was rusting out from under me. I then got rid of the TJ and picked up an '84 CJ with a T-5 about 3 years ago. Alright, now for the problem. When I start the Jeep, everything is quiet. I push the clutch in and there's no noise and it goes into each gear easily still with no noise. Also, the Transfer Case shifts through the gears as easily as it always has. As soon as I let the clutch out it slightly clunks and then there's a scrape scrape scrape scrape scrape noise. It does it in reverse or any of the forward gears. If I'm moving and I push the clutch in or put it in neutral, the noise stops. When I put it in 4-wheel Hi, the noise got even worse. I took both driveshafts off, fired it up and ran through the first couple gears and it was dead silent. Then I put the rear shaft back in (still no front shaft), jacked up the rear tires and there was the noise. A month or so before this started, I replaced the Transfer Case and t5s fluid with syncromesh. Both were still full of fluid, so I eliminated that out of the equation but I did drain the Transfer Case and refill it with gl4. I started thinking it was the Dana 300s output shaft bearings, so i started the hunt for one. The rear has no play whatsoever and the front has just enough play that you can feel it but you can't see it, which I'm told by a guy who I went to buy a Dana 300 from is okay. He suggested I try u-joints, which I replaced to no avail. Someone said it could be the rear axle, but it runs perfectly silet and the noise is clearly coming from the Transfer Case /Transmission area. Then I started thinking maybe it's the pilot, throw out or input shaft bearing on the Transmission . Now I think I'm starting to lose my mind because it's all I'm thinking about. I figured I'd better ask you guys before I go crazy. So, after all that, anyone have any ideas?
 
Check the throw out bearing on the clutch......some clunking can also be engine or tranny mounts.
 
Who's clutch kit did you use?---
You have either a bad pilot bearing in the flywheel, or a dead/dying T/O bearing or BOTH.
You have to pull the tranny to replace them.
Might as well put a whole new clutch kit in. LUK is the best choice here.
LG
 
Obviously the noise sounds clutch related......So I would focus on those moving parts first.......eventually you may have to pull the Transmission and look at the clutch fork, bearing , pressure plate , pilot bearing Etc;

If you have access with a mirror to look in from the side of the bell housing where the clutch fork exits........look in and see if you notice any broken or loose parts.

Have you checked your free-play clearance at the clutch pedal.........meaning at rest is there any clearance in the system / linkage between the pedal and throw out bearing / clutch fork........need at least 1/2"-3/4" of free play.
 
I used a Sachs clutch kit with a new flywheel. I'm not sure who's bearings they use. The pilot is one of the oilite bushings and I soaked in oil for a good two or three days. I guess if I pull the Transmission , I can access the throwout bearing through the hole in the bellhousing? The pedal freeplay is good to go.
 
When I installed a Centerforce in my CJ w/AMC 258 i6 / 4.2l , I did have a wierd noise as well. My first consideration was the throwout bearing, as the noise went away when the pedal was depressed. Replacing the throwout bearing proved that was not the problem. The noise was cured by prying out the dust cover slightly in front of the bell housing. Seems as though the flywheel was scraping against it. Good luck with figuring out what the issue is.
 
Torxhead said:
When I installed a Centerforce in my CJ w/AMC 258 i6 / 4.2l , I did have a wierd noise as well. My first consideration was the throwout bearing, as the noise went away when the pedal was depressed. Replacing the throwout bearing proved that was not the problem. The noise was cured by prying out the dust cover slightly in front of the bell housing. Seems as though the flywheel was scraping against it. Good luck with figuring out what the issue is.
Click to expand...

I'll definitely look at that. Thanks for the suggestion/idea
 
You say new FW-Were the FW bolts torqued and loctited?
You have to remove the tranny to access the T/O.
Did you do the install or have someone else do it?
Have you put a wrench to all the bolts around the tranny and t'case?
LG
 
Lumpy Grits said:
You say new FW-Were the FW bolts torqued and loctited?
You have to remove the tranny to access the T/O.
Did you do the install or have someone else do it?
Have you put a wrench to all the bolts around the tranny and t'case?
LG
Click to expand...

I used those star washers so I didn't use locktite. I did the motor swap myself but I haven't checked the bolts since I put everything together. I'll check those as well.
 
WHY would you use those washers there? :confused:
The OEM setup is no washer of any kind.
What did you torque FW the bolts to in ft/lbs?
LG
 
Lumpy Grits said:
WHY would you use those washers there? :confused:
The OEM setup is no washer of any kind.
What did you torque FW the bolts to in ft/lbs?
LG
Click to expand...

The washers came with the new bolt kit. I honestly can't remember what I torqued the bolts to. I wanna say 60 pounds maybe but I just did a flywheel on a Chevy 235 so I may be confusing the numbers
 
As per my FSM, MR-252 the torque specs is 50 ft/lbs plus 60*.
Did you torque the pressure plate bolts to the FW?
Was the pivot ball on the clutch fork greased?
Have you inspected the clutch linkage pivot points(bellcrank etc)for wear/slop?
LG
 
:agree:
I have seen split-ring lock washers used, but never a 'star' washer.
LG
 
Lumpy Grits said:
As per my FSM, MR-252 the torque specs is 50 ft/lbs plus 60*.
Did you torque the pressure plate bolts to the FW?
Was the pivot ball on the clutch fork greased?
Have you inspected the clutch linkage pivot points(bellcrank etc)for wear/slop?
LG
Click to expand...

The bell crank has a ton of slop in it but everything else mentioned was done
 
The bell crank should probably be greased, and lots of it. If the bell crank shaft is not perpendicular to the frame the motor mounts are shot. It will put excessive load on the outer bell crank pivot and can break the pivot. There are also nylon bushings inside of the bell crank and can easily be replaced. On page D-14 of the M.R.252 factory service manual, there is a blow up of the bell crank assembly.
 
It's amazing what a rebuild clutch linkage kit can make, it's night and day, look at the clutch pedal rod, I would almost bet if it's ome it's got a 3/16 groove wore in it and the bell crank ball studs wear fast when plastic bushings :dung: out the bellcrank pivot studs themselves get lose causing slop.. The piviot ball stud wears causing 1/16in slop. Frame and body flexing over the years throw of alignment 1/8inch... When it comesdown to it even if it doesn't solve the issue it the best thing you can do protect a new clutch from premature wear. I only say this because it was the problem I had when I put a new clutch an couldnt get it dial in perfect with all the stock clutch linkage. Amix-ada has a great kit IV used on both my cj's it's not American but fits and functions nice, just my two cents:chug:
 
The clutch operation is actually really smooth for the amount of play in it. I'm going to pull the Transmission this coming week and have a look at that throwout bearing. I was always under the impression that if the bearing was bad, it made noise when the clutch was pushed in as opposed to when it was let out. Then again, I've never had one go bad so I'm not sure. I'll report back what I find
 
Take the T/O bearing with you to the parts house to be sure you get the correct one.
They are many that look correct-It isn't till you do a side by side do you see the difference.
LG
 
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