GATOR454

Here is a picture of the belt arangement on my '74 LS4 W/ PS & A/C before disassembly:


I believe that this is a kluge by Bubba when the A.I.R. pump was removed. What you can't see in the picture is that the crank pulley is a two groove with an offset from the balancer. The crank pulley also used to be a three groove, but the outer track was cut off. So I believe that the crank pulley is for a long water pump big block.

So the arrangement was like this
Track 1 - No track on the crank pulley, Empty track on the water pump pulley.
Track 2 - Belt around crank pulley, water pump pulley, alternator pulley inner track, power steering inner track.
Track 3 - Belt around crank pulley, water pump pulley, A/C pulley. There is also a belt from the alternator pulley outer track to the power steering pulley outer track.
There is no idler pulley.

Here is what I was thinking of doing.

Purchase a 3-groove crank pulley and a 2-groove water pump pulley.
Track 1 - Crank - WP - A/C
Track 2 - Crank - WP - ALT
Track 3 - Crank - PS

Questions:
1) Does this new arrangement make sense, or are there problems with it or is there a better way?
2) Is there enough adjustment room in the A/C mounting to move it back 2 tracks?
3) or should I move the Alt belt to track 1 and the A/C to track 2? This would require sliding both the Alt and A/C back one track. Is there enough adjustment room in the mounting brackets to move them both back one track?

Any info on how your BB with PS & A/C is belted would be helpfull.

David


[Modified by GATOR454, 8:56 AM 4/1/2004]

Steve's74

Yup, since my '74 arrived sans belts, I sure would like to see the right pictures. David, you are right about the A.I.R. pump missing. In your picture it sat overtop of the waterpump, with a bracket bolted to the waterpump. And my crank pulley is indeed a three groove pulley. However, my alternator only has a single groove pulley. I don't think the original setup had more than one groove, and had a single belt running up from the P/S pump. But since I got the car with no belts, I have no real knowledge. Since I haven't figured out how to post photos yet, I'll shoot you some of the ones that I took. They may not help, with no belts, but all of the equipment is there.

I don't think you will be able to easily move the A/C compressor.

Anyone out there that can help a beltless bigblock?

Steve

sray454

Going from memory on my '72 BB, the #1 belt ( closest to engine ) goes around the crank and water pump only. Because it's an A/C car, it has an idler pulley to adjust tension. #2 belt - next out on the crank is the water pump, crank, A/C, Air pump belt which on mine is now shorten because I do not have the AIR pump either. #3 belt goes between the crank, water pump and inner groove of the power steering pump. #4 belt goes between the outer groove on the power steering pump and the alternator. Only one belt to the alternator.

Hope this helps.

sjr1971

Non-Air no air pump BB '71. :iagree:

R 73 454

Hold the phone! Second opinion! From engine: Belt #1 crank, idler and water pump, Belt #2 crank, water pump and inside track of power steering, Belt #3 water pump, A.I.R. pump, and A/C compressor. Finally Belt 4 runs from outer track of power steering to alternator. Oh and it's a real treat to get them all running true. Power steering brackets especially well designed! The triple groove pulley is a '74 only I think on 454 A/C. I have a '73 454. Your crank pulley seems correct it is a two groove!

GATOR454

Thanks for the replies. I don't have an idler pulley, and since it's a fairly expensive piece not to have I'm trying to avoid the need for one. Also the crank pulley has an offset from the back face to the first groove. the first groove on the crank pulley lines up with the second groove on the water pump pulley. also the third groove was cut off the crank pulley and if it was there the pulley would interfere with the crossmember. These things lead me to believe it is not the original pulley and belongs to a LWP BB engine.

I would still like to know if the ALT and A/C brackets have enough adjustment to move them back a groove, or would I need different brackets. According to my AIM the Alt originally ran off of track 1 and the A/C off of track 2, so I think that they were moved in the past, I just don't know if the brackets were changed when all this happened. I don't want to order the new pulleys just to find out that they won't work once I get to reinstalling the Alt and A/C compressor.

David

Steve's74

Whoops. Told you wrong David. After I got home and looked, I realized that my rat only has a two groove pulley from the factory. Sorry. I'm going to shoot you some pictures of the factory mounts and setups. Don't know if it will help.

Steve

R 73 454

If you want everything to work... hmmm. First, the A/C compressor has ZERO front to back adjustment, sure not a whole pulley track. The crank pulley is only supposed to be a 2 groove! My '74 vette parts book lists the pulley as a '74 with A/C #336098. The 3 groove water pump pulley is listed as a '74 with A/C #336097. For the Alternator pulley, it should be a single groove same one listed for 69-74 Big Block. I don't know what to tell you about the idler pulley, yes it's not cheap. And I can't figure out it's function, seeing as it's not spring loaded, it just rides against inner belt. I have all the part #'s, belt sizes etc you might need, just drop a line. I just don't have a bubba solution for your problem. Regards! :cheers: