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Diagnosing Clutch Rattle

1051 Views 8 Replies 5 Participants Last post by  MrSurly, 
kimchi_king
Been a member here a long time but been pretty absent. @random84 I’m a big fan, your guide for the Monster clutch install was chefs kiss

About 2 years ago, I installed a Monster Triple LT1-S, new slave cylinder, pilot bearing, and rear main seal. About a week after install I start getting a metallic “rattle”, not chatter, from what sounds to me to be coming from the clutch. I also say clutch because I only hear it when I’m stationary and when I depress the clutch, rattle goes away when I left off the clutch. Gear selection does not matter, “it” still rattles. I don’t hear this rattle while driving/moving. Car shifts and has driven fine since install. Any thoughts on what it may be?

I did replace the throw out bearing once and it last about 2-3 days before the rattle returned. Then I replaced the slave again, but it still rattled immediately. Sent Monster pics of the assembly and they said everything looked right. Now I’m debating on sending it in to them for testing.

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RocketSled
What you describe sure sounds like a throwout bearing. You replaced it and the noise went away for a little while. So that would seem to confirm your theory. But the replacement failed quickly. That being the case, the question is "why does this clutch assembly wreck throwout bearings?" The only way I know is if the bearing is still under load even when the clutch has been fully released. Throwout bearings are not designed to be under load continuously, they're only supposed to be loaded when you've pushed the clutch pedal down.

My guess, the clutch is not fully releasing and that's wrecking the throwout.

What does the clutch pedal throw feel like? Is the engagement point near the top or the bottom of the pedal travel?
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kimchi_king
RocketSled said:
What you describe sure sounds like a throwout bearing. You replaced it and the noise went away for a little while. So that would seem to confirm your theory. But the replacement failed quickly. That being the case, the question is "why does this clutch assembly wreck throwout bearings?" The only way I know is if the bearing is still under load even when the clutch has been fully released. Throwout bearings are not designed to be under load continuously, they're only supposed to be loaded when you've pushed the clutch pedal down.

My guess, the clutch is not fully releasing and that's wrecking the throwout.

What does the clutch pedal throw feel like? Is the engagement point near the top or the bottom of the pedal travel?
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near the top. The car had the original clutch when I bought it so I guess the travel feels like a worn Clutch.
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RocketSled
Suggests it may not be releasing fully. I don't know if there's any kind of shim or other adjustment for the slave cylinder/fork, but that's where I'd look.
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kittyboy
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I agree with @RocketSled. I'm not familiar using the clutch assembly you currently have installed. If it is a 'Direct Fitment Part' when installed properly, you may have some other issue to resolve? However, it does sound like you do not have proper air gap clearance and are ridding hard on the throwout bearing based on what you stated.

You might consider installing an adjustable Tilton slave PN: 60-6105. Make sure to first verify compatibility with your clutch manufacturer prior to installing. There is a flat style throwout bearing, and a slightly rounded style throw out bearing available from Tilton for use with the 60-6105 slave. The throwout bearing type is determined based on the clutch assembly diaphragm spring. You will also need to order the Tilton master cylinder line adaptor for OEM CTSV fitment, and a Tick Performance PN: TPSBL bleeder line kit.

I personally have been using a Tilton 6000 series slave for the last 7000 miles and its excellent!

See attached image with slave travel ranges to compare between GM and the Tilton. As you can see, the Tilton is adjustable and will allow you to back-off when adjusting your air gap.

Keep in mind proper air gap measurement for many manual clutches is only between 0.125"-0.20" not much room for error.
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kimchi_king
So I hear what you both are saying, it’s just not clicking in my head. The rattle only occurs when the pedal is down which means the slave cylinder/TO bearing is applying pressure to the clutch fingers, correct?

The clutch kit came with a shim/spacer specifically for the V and last I check a few years ago, the air gap was good. I’ve got it taken apart so I’ll check again.
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Florida-Vee
D
kimchi_king said:
Been a member here a long time but been pretty absent. @random84 I’m a big fan, your guide for the Monster clutch install was chefs kiss

About 2 years ago, I installed a Monster Triple LT1-S, new slave cylinder, pilot bearing, and rear main seal. About a week after install I start getting a metallic “rattle”, not chatter, from what sounds to me to be coming from the clutch. I also say clutch because I only hear it when I’m stationary and when I depress the clutch, rattle goes away when I left off the clutch. Gear selection does not matter, “it” still rattles. I don’t hear this rattle while driving/moving. Car shifts and has driven fine since install. Any thoughts on what it may be?

I did replace the throw out bearing once and it last about 2-3 days before the rattle returned. Then I replaced the slave again, but it still rattled immediately. Sent Monster pics of the assembly and they said everything looked right. Now I’m debating on sending it in to them for testing.

Video of sound
Click to expand...
Did you verify the pilot was the correct diameter to the input shaft nose? and to your above question, yes when the pedal is down the TO bearing is compressing the fingers on the pressure plate and releasing the disc's. Are you certain the disc's are facing the correct way? I don't see how this is a slave issue, unless where the TO bearing rides has been worn (a lot) and allowing the TO bearing to wobble but only at the end of the housing.. I just reinstalled mine and I'm trying to run through all the things that would do this..
Good luck,
Jeff
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kimchi_king
Florida-Vee said:
D

Did you verify the pilot was the correct diameter to the input shaft nose? and to your above question, yes when the pedal is down the TO bearing is compressing the fingers on the pressure plate and releasing the disc's. Are you certain the disc's are facing the correct way? I don't see how this is a slave issue, unless where the TO bearing rides has been worn (a lot) and allowing the TO bearing to wobble but only at the end of the housing.. I just reinstalled mine and I'm trying to run through all the things that would do this..
Good luck,
Jeff
Click to expand...
its an OEM pilot so I imagine it would be correct, but wouldn’t be the first time I’ve received incorrect parts because of a PN mismatch. Even then, the pilot just keeps the alignment, so why only during clutch engagement?

Really you can only incorrectly face one disk in the LT1-S, but it’s stamped which side is which.
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MrSurly
I'm curious if OP found anything new regarding this?
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