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The car in question is a '74 350 auto that came from the factory with AC and P/S.
I'm in the process of removing the AC from the car but I had a question about the P/S pulley. From the factory the P/S pulley uses the third add-on grove on the crank pulley (furthest from the block) and didn't go around the water pump.
But on non-AC cars it seems to go around the water pump as well.
I don't think that I can get away with just removing the AC belt can I? If I do need the P/S belt to go around, do I just need a different P/S pulley or do I need different water pump and crank pulleys as well?
Hello MP,
You should be ok with the pulleys you have on the car. You just need to get a different belt. All the vendors should have one. Here is the part number from Paragon for the 1974 350 PS Pump belt for a 350 w/o air. #13888. I've also included a diagram showing the correct belt installation from my 73 AIM. I don't have AC on my car. The PS Pump uses the 2nd groove pulley on my 73 which should be the same for your 74.
Hope this helps.
Tooch
Last edited by Tooch1; Aug 31, 2017 at 08:54 AM.
Reason: Added info.
Hello Tooch1,
My problem is more to do with the P/S pulley aligning with that second grove as mine sits on a third grove that only exists on the crank pulley. I guess my question is if there is a different P/S pulley I need to get it to line up or if I need to change all of my pulleys to a P/S but non-AC setup. This picture I took should show what I mean a little bit better.
I see what you mean now! Here is another belt routing diagram from my AIM showing the three groove crank pulley with the ps belt on the third groove like yours. Looking at this I don't see why you couldn't just remove your AC belt.?
Tooch
I had thought about just removing the AC pulley and just leaving the P/S one alone but I had doubts because in my mind I figured GM would have made the non-AC cars with P/S belts go around the water pump for a reason. i'll give it a shot and let you know if it works as intended.
Sometimes in this situation, people encounter belt squeal after removing the AC belt. The issue is that the AC equipped cars use a HD fan that requires more power to drive it, with one belt removed from it, the alternator belt is then doing double duty. The fix is to find a short belt that will fit from the water pump to the crank pulleys. Loosen the fan and let the pulley tip down to get the belt on, then tighten the fan. A search on here will probably give you the belt # for this.
It is wise to have two belts going around the water pump, just so you have one (or the other) in case one of the belts fails. That way, your engine won't overheat as you limp back home.
I don't believe that you need to change anything on your engine. You either go with the belts you have and then only have one belt around the water pump; or you get a longer belt for the power steering which would go around the water pump, as well.
If your P/S pulley won't align with the water pump and crank pulleys, you might have to add spacers to the P/S mounting points to get it in alignment.
I ran my 70 (AC & PS) without the AC belt for a couple of years until I found the time and money to restore the AC. I never had any issues. YMMV
I have run mine with only the short belt to the crank pulley without the a/c installed. Didn't make any difference. Use quality brand name belts (it made a difference as far as squealing--- I didn't believe it until it happened to me and I replaced a squealing belt with a good belt).
I ended up removing the AC belt and did experience belt squeak at 3500 rpm. I'm definitely going to look into getting a short belt to run around just the crank and water pump in lieu of the AC belt for the redundancy factor as well as an attempt to stop the squeak.
I didn't have any luck finding a belt for crank / water pump only. Either it was a half inch too long or too short. Keep in mind that a single belt ran everything for decades. I wouldn't worry about doubling up the WP. And you can always keep a spare belt stored in a rear compartment.
Both of those numbers ring a bell. Trouble is, its a lot of work experimenting with different length belts. Loosen Alt, removing the fan, loosen PS belt, bolt up the fan again, etc. I gave up, not that important. So I have an empty pulley groove like the photo above. I would be concerned about putting too much stress on the WP bearing running an extra belt, but thats just my 2 cents worth.
Last edited by HeadsU.P.; Sep 3, 2017 at 03:10 PM.
I ended up removing the AC belt and did experience belt squeak at 3500 rpm. I'm definitely going to look into getting a short belt to run around just the crank and water pump in lieu of the AC belt for the redundancy factor as well as an attempt to stop the squeak.
That might be also a posible not properly tensioned belt...
If you don't have two belts driving the water pump, it will likely squall at you. A/C belt and alt belt will do the job. Or, either one of those and a W/P to crank belt can suffice. The W/P to crank belt is not adjustable; you just loosen the attaching bolts to allow the pulley to tip, install the belt, and tighten the bolts.
AC removal P/S pulley question
