AC Compressor issue

[Mikelly]

Gang, I had a noisy issue withthe engine bay where I though it was the belts/pulley's and swapped out the tensioner and guide pulleys, along with a new belt, then found the noise was actually in the HVAC compressor when the AC was turned on.  So, per searching this forum I found the suggestion of replacing the AC Compressor clutch and pulley/bearing assembly.  So I ordered a refurbished unit and "borrowed" these items and installed them.  I now am the proud owner of a 911 with NO functioning AC.  The system turns on but it doesn't seem like the clutch actuates.  The hub is magnetized when I turn the ignition on, but the clutch doesn't seem to actuate and the system is not blowing cold air.  I'm looking for suggestions. 

 

[creekman]

Mike or Kelly, or shared address, or none of my business...  Anyway the compressor clutch is extremely sensitive to the gap of the pulley to the plate.  I'd measure the gap, I 'think' it should measure in thousands of an inch.  Have you checked to be sure you have 12V.  I have sympathy for you since I have somewhat the same condition.  It has taken as long as 10 minutes before the clutch engages .  For reason that delay has come down to less than 5 minutes.

 

Mitch

[Mikelly]

1 hour ago, creekman said:

Mike or Kelly, or shared address, or none of my business...  Anyway the compressor clutch is extremely sensitive to the gap of the pulley to the plate.  I'd measure the gap, I 'think' it should measure in thousands of an inch.  Have you checked to be sure you have 12V.  I have sympathy for you since I have somewhat the same condition.  It has taken as long as 10 minutes before the clutch engages .  For reason that delay has come down to less than 5 minutes.

 

Mitch

It’s Mike Kelly.  I’ve been around since 2007 and wrote a BUNCH of tech articles when I was running the 996TT 30 track days per year.  So I checked the airgap and added an extra shim because it seemed to rub against the the hub and was dragging.  Now it’s not engaging at all.  I’ll measure the air gap.  Thanks.  

[Mikelly]

Fixed.  Replaced the old clutch and shims and it works, strangely enough.  Little bit noisy.  I may end up trying the new clutch with the old shims.  But for now it works. 

 

Mike