Clutch setup video

Mattp

Member
Messages
501
That's just what I need, at just the right time!

Is what this guy says all correct???
 

tulit

Member
Messages
110
That's just what I need, at just the right time!

Is what this guy says all correct???
No. The description of how the clutch wear index relates to PIS and how to set the PIS is wrong.

Sent from my SM-A515W using Tapatalk
 
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Gp79

Member
Messages
1,393
No. The description of how the clutch wear index relates to PIS and how to set the PIS is wrong.

Sent from my SM-A515W using Tapatalk
Please could you expand on that.
what is the correct way and where can the information be found?
 

tulit

Member
Messages
110
You can have a look at a document called "Advanced Electronics 1" from the Maserati academy, but in short, the PIS is not some unitless measure. Its the amount the throwout bearing is moved from a fully closed clutch to when you tell it the clutch should start biting (as a result it self corrects for any wear/etc).

The wear index itself should be reset (to 4000) using the scan tool after a clutch change BEFORE the PIS is set. The wear index controls the transmissivity curve (e.g. how the clutch moves between the PIS and fully closed state) and is a measure of slippage.

The workshop manual even clearly states:
"Note: the clutch wear index must be reset (= bring back to the default value of 4000) after replacement of the clutch and before performing the Kisspoint procedure."
(note kisspoint and PIS are used synomously)

Note that the procedure varies slightly depending on the version of SoFast. This is for SoFast II which 4200 cars have.

More details on PIS and clutch operation here (doesn't go into the resetting the index needed on a clutch change) - https://italianautotech.com/2021/01/03/setting-clutch-pis/
 

Gp79

Member
Messages
1,393
You can have a look at a document called "Advanced Electronics 1" from the Maserati academy, but in short, the PIS is not some unitless measure. Its the amount the throwout bearing is moved from a fully closed clutch to when you tell it the clutch should start biting (as a result it self corrects for any wear/etc).

The wear index itself should be reset (to 4000) using the scan tool after a clutch change BEFORE the PIS is set. The wear index controls the transmissivity curve (e.g. how the clutch moves between the PIS and fully closed state) and is a measure of slippage.

The workshop manual even clearly states:
"Note: the clutch wear index must be reset (= bring back to the default value of 4000) after replacement of the clutch and before performing the Kisspoint procedure."
(note kisspoint and PIS are used synomously)

Note that the procedure varies slightly depending on the version of SoFast. This is for SoFast II which 4200 cars have.

More details on PIS and clutch operation here (doesn't go into the resetting the index needed on a clutch change) - https://italianautotech.com/2021/01/03/setting-clutch-pis/
Thanks for that, I’ll have a read up.
 

hladun

Member
Messages
149
At 6:10 of the video he talks about clutch bleeding but he doesn't seem to understand how this actually works. The service manual describes the correct procedure. You use the pump to pressurise the system but you have to simultaneously open the bleed screw at the clutch to allow the air out when you're doing this. Otherwise you end up with the air in the system and soon it's good bye clutch. He says something about the pressure relief valve opening to release pressure but that's not the same because it doesn't get the air out.
 
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Gp79

Member
Messages
1,393
At 6:10 of the video he talks about clutch bleeding but he doesn't seem to understand how this actually works. The service manual describes the correct procedure. You use the pump to pressurise the system but you have to simultaneously open the bleed screw at the clutch to allow the air out when you're doing this. Otherwise you end up with the air in the system and soon it's good bye clutch. He says something about the pressure relief valve opening to release pressure but that's not the same because it doesn't get the air out.
As far as I understood that part was just a demo of the clutch bleed on the diagnostics, it would have been bled before at the bell housing. he does actually mention getting the reservoir topped up as its bled from the underside.
I don’t think it would even run if it wasn’t bled, a new release bearing full of air etc
 

conaero

Forum Owner
Messages
34,594
When we bleed a clutch, it’s a three person affair.

One filling the reservoir
One opening and closing the bleed screw
One (usually me) up on the ramp arm leaning through the window with scantool triggering the pump and cutting the ignition to stop the pump.

This is so you don’t burn the pump out which is very easily done.
 

hladun

Member
Messages
149
As far as I understood that part was just a demo of the clutch bleed on the diagnostics, it would have been bled before at the bell housing. he does actually mention getting the reservoir topped up as its bled from the underside.
I don’t think it would even run if it wasn’t bled, a new release bearing full of air etc
So what you're saying is that if it was done right before then doing it wrong now has no effect. I guess I can't argue with that.
 

Mattp

Member
Messages
501
When we bleed a clutch, it’s a three person affair.

One filling the reservoir
One opening and closing the bleed screw
One (usually me) up on the ramp arm leaning through the window with scantool triggering the pump and cutting the ignition to stop the pump.

This is so you don’t burn the pump out which is very easily done.


That sounds like a bleed procedure!