New clutch squeals at idle

[Clifford Heath]

Clutch on Liberty 2.5 RX was replaced when HG rebuild done
in August. Now there's a squeal coming from the clutch while
the engine is idling. At first I thought it sounded like a
fan-belt squeal, and in fact I did just have to replace the
P/S & alternator belt, which hadn't been tightened properly
and wore out. However the squeal stops when the pedal is
depressed, and I think also when the car is in motion. All
oil levels are ok.

What's the noise likely to be coming from? Bearings, slip
ring, ...?

 

[Edward Hayes]

Clutch misadjusted causing the throughout bearing to spin even when
the clutch is disengaged?

 

[Steve]

Did you also change the throw out bearing?

 

[S]

Hi Clifford!

Clutch on Liberty 2.5 RX (snip) However the squeal stops when the pedal is
depressed, and I think also when the car is in motion.

Noise when idling with tranny in neutral, clutch engaged?

Probably not throw-out bearing; noise would get worse when clutch
pedal depressed.

Probably not clutch friction plate; slippage highly unlikely with no
load on engine.

Could be the face of the throwout bearing is just touching the fingers
of the pressure plate. I can see where this might make a little noise;
does the sound go away with light pressure on the pedal, or do you
have to depress far enuf to dis-engage the clutch?

Could be the transmission input shaft bearing; I had a similar issue
with a Suzuki Samurai I once owned.

FWIW, the input bearing can be damaged by inexpert handling when
mating the engine to the tranny, either as a result of supporting the
weight of the engine on the tranny input shaft, or from forcing the
engine/transmission mating (by using the bell-housing bolts to pull
them together) in the event of improper clutch alignment.

Could be something else entirely; use a mechanics stethoscope (a $10
item at the auto parts store) to pinpoint the sound.

ByeBye! S.

Steve Jernigan KG0MB
Laboratory Manager
Microelectronics Research
University of Colorado
(719) 262-3101

 

[Clifford Heath]

Steve,

Noise when idling with tranny in neutral, clutch engaged?

Thanks for your thoughts. Still no resolution of this, but
I do have more information. Both the throwout bearing and
the spigot bearing (what's that do?) were replaced with the
clutch in August. The noise occurs whenever the clutch is
engaged, whether at idle or moving.

Could be the face of the throwout bearing is just touching the fingers
of the pressure plate. I can see where this might make a little noise;
does the sound go away with light pressure on the pedal, or do you
have to depress far enuf to dis-engage the clutch?

The sound changes as the clutch disengages, and goes away when it's
fully disengaged.

Could be the transmission input shaft bearing; I had a similar issue
with a Suzuki Samurai I once owned.
FWIW, the input bearing can be damaged by inexpert handling

Ouch, I hope it isn't this. Sounds pretty likely though. :-(
In any case it can't be diagnosed without pulling it apart, I
guess.

Could be something else entirely; use a mechanics stethoscope (a $10
item at the auto parts store) to pinpoint the sound.

I thought of that, but how do you get to listen to the different
parts of the clutch/gearbox, it's encased? The sound is clearly
coming from there.

 

[Michael Pardee]

Steve,


Thanks for your thoughts. Still no resolution of this, but
I do have more information. Both the throwout bearing and
the spigot bearing (what's that do?) were replaced with the
clutch in August. The noise occurs whenever the clutch is
engaged, whether at idle or moving.


The sound changes as the clutch disengages, and goes away when it's
fully disengaged.


Ouch, I hope it isn't this. Sounds pretty likely though. :-(
In any case it can't be diagnosed without pulling it apart, I
guess.


I thought of that, but how do you get to listen to the different
parts of the clutch/gearbox, it's encased? The sound is clearly
coming from there.

Mostly I rely on what makes the sound change, and correlating that with the
actions of things (particularly the bearings). Sometimes it comes out wrong
(I recently thought a spring that had popped out of a disc was a seized
pilot bearing) but it's worth a try.

The throwout bearing normally doesn't spin unless pressure is placed on the
clutch pedal, so that doesn't match the symptoms. The pilot bearing (must be
what they call a "spigot bearing" - goes in the flywheel to support the end
of the input shaft) spins when the pedal is depressed enough to disengage
the clutch, so that also doesn't match.

Sadly, the input shaft bearing (which can be damaged if the tranny isn't
properly supported during removal and reinstallation) fits the profile:
spins when the clutch is engaged, but not when disengaged. If that bearing
is the squealer, it will show up when you jack up the wheels (can this be
done with just the front wheels on the Subie AWD?) and rotate a wheel by
hand while the tranny is in gear and the clutch depressed. Shifting to
neutral would stop the squeal, even with the clutch disengaged.

I don't see any solution but to remove the tranny again :-(

Mike

 

[Clifford Heath]

I don't see any solution but to remove the tranny again :-(

Thanks for your quick response. I'll let you know how it goes.
Unfortunately the engine work was done 200 miles from here, so
I'm not going to just "take it back to the store" :-(.

 

[Clifford Heath]

I don't see any solution but to remove the tranny again :-(

The Subaru dealer service folk think that the clutch throwout
bearing was fitted incorrectly and the coupling has come loose.
The slave cylinder lever seems to wobble about even at idle
when it should be still. I haven't seen the throwout bearing,
but he mentioned forks and some ball arrangement which he
thinks wasn't tightened correctly.

So they're going to pull the tranny, 6 hours work... the earlier
repairer seems prepared to take responsibility as long as he
gets some evidence from a 3rd party that it was their fault, so
we'll see, negotiating now.

 

[Michael Pardee]

The Subaru dealer service folk think that the clutch throwout
bearing was fitted incorrectly and the coupling has come loose.
The slave cylinder lever seems to wobble about even at idle
when it should be still. I haven't seen the throwout bearing,
but he mentioned forks and some ball arrangement which he
thinks wasn't tightened correctly.

So they're going to pull the tranny, 6 hours work... the earlier
repairer seems prepared to take responsibility as long as he
gets some evidence from a 3rd party that it was their fault, so
we'll see, negotiating now.

Here's hoping! Good luck, Clifford.

Mike

 

[Clifford Heath]

Here's hoping! Good luck, Clifford.

Ok, all fixed - except the cash ($AU770). The throwout bearing has
two clips, only one of which was fitted, so the assymetric pressure
caused failure after only 7000km. Also, there was no grease on the
face of the gearbox where the bearing was in sliding contact, so
the face was scored and had to be linished back. So all up, a
plainly incompetent job for which I intend to make the repair shop
pay. They're reputable and claim to stand by their work, so it
shouldn't be too much drama, I hope.

Clifford Heath.

 

[Edward Hayes]

WOW; It appears that they did not put a real mechanic on your clutch
replacement or even have it checked by a mechanic: I've seen this too
many times. My dealer actually has the guy who cleans up the shop
floor doing oil changes when their behind on their service and for
this they want to charge me $85/hour to "expert service" work?