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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: GMCStepper76 on July 29, 2012, 07:02:39 pm

Title: 76 GMC K15 A/C quetion
Post by: GMCStepper76 on July 29, 2012, 07:02:39 pm

Hey all,

I'm sure this has been asked and answered before but I cant find exactly what I need.

I have a 76 GMC K15. I am doing a cab swap. My old cab did not have A/C. My new donor cab does. Its off a 76 Chevy 3/4 ton 2WD longbed.

I have a couple questions about the A/C system. The ac box is on the passenger side. I did not pay attention when I stripped the donor truck for the swap. I have ALL the A/C pieces I just don't know which side the compressor goes on. The donor truck had a 454. I have A/C brackets for the 350 in my truck now. Can someone give me a quick rundown, I also will need new pulleys to run the compressor I just don't know which pulley actually turns the compressor. If anyone has a pic that would also be VERY helpful.

I think I need a 3 groove pulley for the crank and a 2 groove pulley for the water pump. The truck has Power Steering as well.

Thanks in advance Guys. I appreciate your time.
Tony

Title: Re: 76 GMC K15 A/C quetion
Post by: Jason S on July 29, 2012, 11:27:40 pm

If your A/C brackets are for the '76 GMC, then the compressor should be an A-6 style mounted on the driver's side of the engine. 
The crankshaft pulley actually turns the compressor.

Both of my trucks ('73 and '74) have  a 3 groove crank pulley, 2 groove waterpump pulley and 2 groove power steering pulley. 

Brackets for a '74 Chevrolet smallblock V8
(https://lh6.googleusercontent.com/-f_PkGjZb_aA/UBYHGHzHLDI/AAAAAAAAAoY/7XFriK5Er3c/s640/DSC03691.JPG)

Brackets for a '79 Chevrolet smallblock V8
(https://lh5.googleusercontent.com/-x0aiHNrSKgQ/UBYHH5fXEmI/AAAAAAAAAog/WFKWQnEX-Bo/s640/DSC03692.JPG)

Belt routing for a '79 Chevrolet smallblock V8 - non-California  (lower right for P/S and A/C)
(https://lh5.googleusercontent.com/-DTJSRb1ObuU/UBYHNLJejzI/AAAAAAAAAqo/2P3lkl1R1t8/s640/DSC03695.JPG)

Belt routing for a '79 Chevrolet smallblock V8 - California (lower left for P/S and A/C)
(https://lh6.googleusercontent.com/-zUMrUBu7kYQ/UBYHTmNlD6I/AAAAAAAAAqs/hIwMQBWljG0/s640/DSC03699.JPG)

Additional A/C compressor adjustment info from '79
(https://lh3.googleusercontent.com/-XWtsvYw1rxQ/UBYHWqhGUdI/AAAAAAAAAqw/RhbGwjbHZxc/s640/DSC03701.JPG)

Waterpump, power steering and crankshaft pulley on my '74 Chevrolet K10
(https://lh4.googleusercontent.com/-r-rdrzkkNh0/UBYHY_fO-yI/AAAAAAAAApw/WpMraihFiIk/s640/DSC03703.JPG)


Photos from my '74 Chevrolet K10 (350 with centerbolt valvecover heads).  My setup isn't absolutely factory correct, but it works very well.
View of waterpump, powersteering and crankshaft pulley.
(https://lh3.googleusercontent.com/-Axt40IIaoTU/UBYHaW4XX5I/AAAAAAAAAp4/5Kba3scb2Mc/s640/DSC03705.JPG)

View from compressor of waterpump, powersteering and crankshaft
(https://lh3.googleusercontent.com/-2A6MaEzicmA/UBYHd0MNVPI/AAAAAAAAAqA/Pv1bjH9zMqI/s640/DSC03708.JPG)

View of compressor mounting
(https://lh4.googleusercontent.com/-JtwDO0wnTFg/UBYHicIAbhI/AAAAAAAAAqI/gwMko0nH0ng/s400/DSC03709.JPG)

View of compressor mounting brackets at intake manifold
(https://lh6.googleusercontent.com/-AiDVE7WHV0s/UBYHk8dg6uI/AAAAAAAAAqQ/9NN8LeLR9Z8/s400/DSC03710.JPG)

View of lower compressor mounting brackets.  Note: the power steering mounting bracket is modified from a non-A/C bracket. 
(https://lh5.googleusercontent.com/-hDaJYI7ZFXA/UBYHnUIVg2I/AAAAAAAAAqY/s5sZpHQUVWU/s640/DSC03711.JPG)

Hope this helps a little bit.