Technical Driving a Sanden single v compressor off the water pump?

I made a real rookie error in my cooling system layout where in my lower radiator outlet is smack in the middle of where my A/C drive belt wants to run. I'd hate to relocate the neck on my new $800 radiator. So my idea is to run the compressor just off the water pump pulley, and not the crank. Will this work, or will it slip?

 

Do you have room for an idler pulley? I'll apologize for the crudity of the drawing; I'm still working on my first cup of coffee.

 

Not to be a buzz kill but wouldn’t the headers wrapping around that close to the compressor cause issues? Not that I’m saying that it would but that is a lot of heat to have around the hoses and such.

 

I'm running V belts, Alan. Can't "back bend" those, can I?

 

It's not as bad as it looks, how about this angle?

 

Chrysler in the 70s or 80s use an idler pulley on a/c & alt. v belts

 

You can get a backside idler also. But V belts can bend. You can run the compressor on single belt. But being that long Id be afraid it would slip. Can you change the ac bracket to locate the compressor up by the valve cover?

 

Based on my years designing mobile HVAC systems, I think you’ll be fine with the belt running off of the water pump pulley. I’d be more concerned about the length of the upper brkt and the comp wanting to twist when tensioned.
Also, that header seems awfully close to the compressor. Remember any heat absorbed into your suction line (coming from the evap), will reduce your AC efficiency as it will increase your suction press which will increase your discharge pressure accordingly, which will result in higher refrigerant temps which will will result in hotter air coming off the condenser which means hotter intake air temps into the rad which means higher coolant temps.

 

Why not? Works on my JD mower deck, seems to work on this other guy's hovercraft.

 

Can you find a moulded hose with a big dip in it, or make one out of metal tube with straight hose on each end to connect it to the engine and radiator.

 

One thing I would do is move the compressor closer to the block. From the rear view Pic it looks like you could move in a couple inches. This would help strengthen the brackets and help fight some of the flex/twist problems that may arrise.

I'd also weld a tab onto the backend of the bracket bolted to the block so that I could bolt a bracket from that tab to the back of the compressor.

I wonder though what kind of side load you'd put on just the water pump bearings with the belt.


...

 

Yes , back side of V belts ,
& custom make tight
Coolant & other

 

Try it and see!
I mounted the Sanden on the original generator bracket on the Buick Straight Eight. Then a bracket mounted on top of the Sanden took care of the alternator. Sanden driven with crank/fan belt. Alternator driven off 2nd groove of Sanden. Works for me.

Ben

 

Sounds like this thinking outside the box would solve this whole problem and could put the a/c on the same side as alt.

 

Many ways to skin a cat!

 

Will work fine; the 180-degree wrap means the AC belt won't slip. The only limitation is do you have enough wrap on the crank to water pump pulley? Since it has to handle twice the load, it needs traction.

jack vines

 

https://www.aircomponents.com/produ...Vk66YTFztOPulZMd2X9LwDGsjQKai3I3xOebl9DKjQnu3

https://www.mcmaster.com/products/idler-pulleys/belt-type~flat/

 

Thank you, Alan. I didn't know of any applications that use V-belts that back-bend, well, except lawn tractors. I assumed that only worked at low RPM.

 

Thank you. The position the compressor is in is where it fits and looks best. I have mirror brackets on the other side for the alternator. Maybe I can add another slider/bracket and a heat shield to the rear of the compressor.

 

Thanks for responding. There's just not enough space for a hose with a jog.

 

Thank you. Not much room for inboard relocation, but I agree, I could do with more rigidity.

 

Thank you for responding. Not much room for a Z shaped tube there though.

 

I think that's the plan. I can always improve it.

 

Thank you. This thing is all about the look- I'm trying to make it all symmetrical...the engine is open, no hood..

 

Thanks, Jack. That's the real question. Is there enough grip on the other belt to drive it all???

 

Great response Gimpy! Thank you.

 

I appreciate everyone's responses here. I gotta tell you guys, this has been a humbling thing for me, been beating myself up about it all weekend. This whole drive system I basically copied from another set of brackets I built long ago for my Studebaker when it had a BBC, but in mirror image. In fact, I had the alt on the driver's side initially, which as you know has a smaller pulley, that had good clearance, but swapped it all to to opposite sides for plumbing and wiring neatness concerns. Somewhere in the mock up phase on my engine stand, it totally escaped me that the larger pulley of the compressor would conflict with the lower hose. I think I'm gonna wing it and see what it does as far as slip, as I can add a back side pully and longer belt if it won't work. And I an looking at adding a rear slider bracket/stiffener to the compressor. Thanks, guys.

 

Those are some really good looking brackets!!

 

Didn’t see the other comp mtg brkts in the previous pics. Haha! Don’t think you need any more brkts. If I’m seeing correctly it appears the brkts are sitting on top of spacers. Not sure how well that will work out in reality. Believe it or not a lot science/engineering goes into accessory mtg brkts to eliminate resonate vibrations. You might want to join the front and rear lower comp mtg brkts with a gusset. You’ll only know once you fire it all up.
Heat shield would be a good idea as the heat from the header could shorten its life as max temps they (comp) typically would see around 250F - 300F.