AC belt too short

[dapiper]

Stock size too short, next size too long. All '77 OEM. Why? Maybe boneyard gave me '79 AC and compressor mtg brkt different? Hate that belt squeal during start-up.

 

Does AC compressor have swing adj like alt?

[HizAndHerz]

Stock size too short, next size too long. All '77 OEM. Why? Maybe boneyard gave me '79 AC and compressor mtg brkt different? Hate that belt squeal during start-up.

 

Does AC compressor have swing adj like alt?

 

Stock '77 AC has an adjustable idler pulley and compressor bolts solid to a steel bracket. The 280ZX compressor mount is different (aluminum). The ZX AC pulleys all use a thinner belt than the 280Z to make room for the extra power steering belt. Most dealer installed compressors I've seen use a swing adjust bracket for the compressor.

 

Do you have a Hitachi SWP167 compressor? If not, it is most likely from a dealer installed AC system and you'll need a different bracket or a different compressor.

[zcarnut]

...The 280ZX compressor mount is different (aluminum). The ZX AC pulleys all use a thinner belt than the 280Z to make room for the extra power steering belt..

 

Some clarification: The early ZX’s AC compressor used the wide belt like on the 1974-78 Z’s. The power steering pulley was a stamped steel piece that was bolted to the front of the harmonic balancer. They also used the same cast iron mount as the early Z cars.

 

The later ZX’s changed to the thinner belt. According to a Nissan TSB it was done to reduce belt drag.

 

The compressor mount was changed to aluminum when the mount was re-designed for the ZX turbo engine. A mounting boss was added for the crankshaft timing pickup. Nissan then just used the aluminum mount on all the NA ZX’s.

[dapiper]

Thanks guys, guess I should have specified; using '77 OEM from Roger at ZBarn in TN. Guess the compr is fixed, but that doesn't explain why stock belt too short. Found one 1/2" longer at 37.5" will try that.