A/C Compressor Question:ZR-1 Vs LT1

[zrwhat]

Can anyone tell me what the difference is between our ZR-1 A/C Compressors and those from a L-98 or LT1 car?

One of my ZR-1s seems to have an issue with the serpentine belt chaffing on the engine side and the belt is riding on the edge of the pulley,

My guess is someone changed out the compressor and it has the wrong offset causing the pulley to set further forward then the correct ZR-1 compressor.

Any ideas?

Gibby

[Dynomite]

AC compressors are completely different (LT5 and L98). Including Mounting and Compressor ports.
On LT5, distance from center of drivers side front AC Compressor mounting bolt and rear edge (closest to engine) of Serpentine belt is 1.25 inches.

[zrwhat]

Thanks Dyno,

I wonder if maybe the clutch assembly for the A/C may have been changed out and installed but not taken as far as it needs to go causing the pulley to be forward too far making the belt to ride on the pulley shoulder towards the rear chaffing the edge of the belt?

Might be time to pull the Plenum and take a look-see....

[Dynomite]

Originally Posted by zrwhat

Thanks Dyno,

I wonder if maybe the clutch assembly for the A/C may have been changed out and installed but not taken as far as it needs to go causing the pulley to be forward too far making the belt to ride on the pulley shoulder towards the rear chaffing the edge of the belt?

Might be time to pull the Plenum and take a look-see....

See if you have 1.25 inches distance from center of drivers side front AC Compressor mounting bolt and rear edge (closest to engine) of Serpentine belt.

I am the one that should have issues with pulleys
I have Randy Woods Power Steering and Water Pump pulleys, Delco CS130D Alternator 6 Groove Pulley, and UPR Billet Aluminum Belt Tensioner Pulley.

[A26B]

Originally Posted by zrwhat

Thanks Dyno,

I wonder if maybe the clutch assembly for the A/C may have been changed out and installed but not taken as far as it needs to go causing the pulley to be forward too far making the belt to ride on the pulley shoulder towards the rear chaffing the edge of the belt?

Might be time to pull the Plenum and take a look-see....

Look closely under the accordian air tube where it is clamped to the air horn. Very little clearance under there and I have seen the belt rubbing the clamp & chafe the belt. May need to move the clamp a little to get it away from the belt.

[zrwhat]

Originally Posted by A26B

Look closely under the accordian air tube where it is clamped to the air horn. Very little clearance under there and I have seen the belt rubbing the clamp & chafe the belt. May need to move the clamp a little to get it away from the belt.

Thanks for the tip Jerry,

Has a Samco coupler and no rubbing from the clamp.

When you look at the A/C Compressor pulley from the side, you can see the belt riding up on the rear edge of the pulley, I thought maybe someone did not center the belt on the pulley when installed so I took tension off the Belt Tensioner and re-centered the belt on the pulley, only to have it go back to rubbing on the edge of the rear of the pulley once started which is telling me the pulley is too far forward by about 1/8" or more.

Gibby

[Dynomite]

Originally Posted by zrwhat

Thanks for the tip Jerry,

Has a Samco coupler and no rubbing from the clamp.

When you look at the A/C Compressor pulley from the side, you can see the belt riding up on the rear edge of the pulley, I thought maybe someone did not center the belt on the pulley when installed so I took tension off the Belt Tensioner and re-centered the belt on the pulley, only to have it go back to rubbing on the edge of the rear of the pulley once started which is telling me the pulley is too far forward by about 1/8" or more.

Gibby

Are the Power Steering Pump Pulley and AC Pulley in line?
It is unlikely the AC Pulley is out of line with Power Steering Pump Pulley and Harmonic Balancer Pulley.
Look from Passenger side and check alignment of Alternator Pulley and AC Pulley.
Does the Serpentine Belt ride on those other three pulleys correctly?

[zrwhat]

It appears the belt is riding correctly on all pulleys except for the A/C pulley, next step is to see if the A/C Clutch unit is fully pressed onto its shaft, only thing I can think of to cause just 1 pulley to be out of sync.

I'll be away from the car for a few days but will look and report back.

Thanks

[Dynomite]

Originally Posted by zrwhat

It appears the belt is riding correctly on all pulleys except for the A/C pulley, next step is to see if the A/C Clutch unit is fully pressed onto its shaft, only thing I can think of to cause just 1 pulley to be out of sync.

I'll be away from the car for a few days but will look and report back.

Thanks

Now you have my interest
I will go out now and take a picture of my measurement of that AC pulley location precisely with respect to something fixed on the engine so you can compare to what I have within 1/16 inch....if possible.
I will also take same measurement on that crate engine to verify (comparing a 91' to a 95').

There is some play in the bolt holes of the AC when you sit it in position which may contribute to its final position forward or rearward on the engine block.

95' Air Horn - 15/32


95' AC - 1/2


91' Air Horn - 19/32


91' AC - 17/32

[zrwhat]

There is some play in the bolt holes of the AC when you sit it in position which may contribute to its final position forward or rearward on the engine block.

BINGO!

My answer may lie here in this statement above if movement is possible within the mounting holes.

If the compressor is too far forward, could be causing the "rub" on the rear most edge of the A/C pulley shoulder (actually riding on the raised pulley edge).

Gibby