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ericoneal
Whenever I start my car when its cold and press the clutch, its making an awful rattling sound, even at idle. The noise increases as a push on the clutch pedal and from my research on here and YouTube, it sounds like the throw-out bearing on the transmission.
The odd part of all of this is that it only happens when the engine is cold. Once I let her warm up for a few minutes, the noise is gone by the time I'm leaving the house (Reverse, then Forward, then no more sound) Everything seems to be shifting fine and the noise disappears.
Something is going on down there, do you guys think its safe, mechanically, to drive it like this for awhile or will a worn throw-out cause more damage?
Seems like an easy fix as soon as I can get time to drop the tranmission.

solex
I had a similar problem except that when I pressed the clutch the sound went away. I cannot comment on how long it will go before failing, but given the cost of everything around the bearing I would replace it sooner rather than later.
ericoneal
I'm thinking the same, may need to clear my weekend. sad.gif
ericoneal
So I got the throw-out bearing installed and the car put back together. Still sounds the same, so I've wasted a whole week under this POS.

Can someone have a look at this video and give me an idea of what else this could be?

914 clutch noise

It shifts just fine, and the noise lessens as the car warms up until it just goes away all together after a few minutes.

Not sure what to do at this point..

zipedadoo
It sure sounds like a release bearing to me. I would get back under the car and remove the clutch cable and then try to release the clutch by hand. Granted you wont be able to move the lever much but maybe you'll get a better feel for whats going on. Also have some one push the clutch in as you watch from underneath maybe a worn mount or something moving around thats not supposed to.
IronHillRestorations
Sorry you are having trouble Eric.

If you replaced the TOB and it sounds the same, then it's probably not the noise.

Sounds to me like something in the pressure plate or the clutch disc. Did you take off the PP when you replaced the TOB?
Mark Henry
agree.gif
That's not the sound of any release bearing I've heard failing. Usually would sound a lot like a wheel bearing failing, real bad you would feel the grind right through the pedal.

First thing is to get a buddy to press on the clutch, crawl under and isolate where the noise is coming from.
Do you feel that right through the pedal?

My first guess is you have a busted pressure plate spring. Or the spring rivets have let go or it has broken spring fingers.
The PP has a diaphragm spring I bet it has cracked all the way around and part of it is letting go or it has totally failed and the shoe is spinning and hitting whatever is left of the rivets.
This may be hard to spot as it's sandwiched between the PP cover and shoe.

Although different spring type I had a type 1 PP arm (KEP stage 1) let go and it sounded similar.
If I'm right only cure is a new or good used Pressure Plate.
ericoneal
I took the car out yesterday for a quick drive around the block a couple of times, and it shifted and ran great. Also, the noise was gone by the time it had warmed up for 2-3 minutes before my drive and was not there while I was driving at all.
Its all very odd. If it were the clutch, there would be issue while driving, right? I'm thinking, maybe just wishful, that its something else at this point. Will get it under tonight or tomorrow and search closer using zipedadoo's approach. Perry, I did not touch the clutch while I was under there, just replaced the TOB and put it back together.


Thanks all,
Eric


QUOTE(Mark Henry @ Jul 31 2017, 07:52 AM) *

agree.gif
That's not the sound of any release bearing I've heard failing. Usually would sound a lot like a wheel bearing failing, real bad you would feel the grind right through the pedal.

First thing is to get a buddy to press on the clutch, crawl under and isolate where the noise is coming from.
Do you feel that right through the pedal?

My first guess is you have a busted pressure plate spring. Or the spring rivets have let go or it has broken spring fingers.
The PP has a diaphragm spring I bet it has cracked all the way around and part of it is letting go or it has totally failed and the shoe is spinning and hitting whatever is left of the rivets.
This may be hard to spot as it's sandwiched between the PP cover and shoe.

Although different spring type I had a type 1 PP arm (KEP stage 1) let go and it sounded similar.
If I'm right only cure is a new or good used Pressure Plate.

Mark Henry
Like I said get a buddy crawl under and isolate the noise.
ericoneal
Still have this noise happening, only when the engine is cold, or at least thats only when its noticeable.
I had my wife push the clutch with me under it, dont see anything obvious. Engine and transmission mounts seem to be fine at a glance.
Whats odd is that it seems to me to be coming from near the fan, or at least near the front of the engine. It also seems to be correlated with RPM. Maybe a fan bearing? Still does not explain why the noise goes away when the engine is warm?
Also adjusted the valves for good measure to no effect.

Any ideas here would be great.

Thanks,
Eric
Mark Henry
Hmmm... pray I'm wrong on this one.
You have to figure out a way to push/pull the fan and check for play.
You might be able to pry the flywheel through the little window on the bottom of the trans. You looking to see how much end play the crank has, .006" is the limit which would be barely noticeable by eye.
If it goes clunk-clunk, as in lots of play, or you can definitely see it move, that's bad news.
ericoneal
K. Will try that.
Why exactly is it bad news, and any thoughts on why it would only happen when engine is very cold?

ALso, the engine only has about 1000 miles on it since it was rebuilt. No issues until now.

QUOTE(Mark Henry @ Aug 6 2017, 04:38 PM) *

Hmmm... pray I'm wrong on this one.
You have to figure out a way to push/pull the fan and check for play.
You might be able to pry the flywheel through the little window on the bottom of the trans. You looking to see how much end play the crank has, .006" is the limit which would be barely noticeable by eye.
If it goes clunk-clunk, as in lots of play, or you can definitely see it move, that's bad news.
zipedadoo
Pull your fan belt/ belts. Just to make sure it's not the alternator or a/c if you have it.
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