Am I going to throw a belt doing this?

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ESP47

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The plan is to run a belt on the inner groove of the crank for the water pump and alternator. Outer groove of the crank for the compressor and power steering. Problem is that it also runs down the outer groove of the water pump pulley. I have a feeling this is a no go but I wanted to check here first.

My one groove pulley doesn't line up with anything and I'm afraid the one grooves I buy online probably won't either. I've got a weird setup. Magnum 360 block, borgeson pump and sanden compressor with the buchillion bracket for the magnum engine and passenger side offset thermostat housing.

IMG_20230814_190320832_HDR.jpg
 
IF it is aligned and IF the water pump and crank both have the same groove diameters, you should be OK

If it does seem "long" you might consider constructing an idler on that long side to pull it in towards the center
 
67Dart273 said:
IF it is aligned and IF the water pump and crank both have the same groove diameters, you should be OK

If it does seem "long" you might consider constructing an idler on that long side to pull it in towards the center
Click to expand...

Thanks they're both from CVF and they basically line up perfect.

The belt is too long but I was just using it as a prop to show the issue I had going on.
 
No, it won't throw it I don't believe, but that's nowhere near enough belt coverage to drive the water pump. Will you have another belt in play for the water pump?

Nevermind. I'm blind. I re-read it. lol
 
RustyRatRod said:
No, it won't throw it I don't believe, but that's nowhere near enough belt coverage to drive the water pump. Will you have another belt in play for the water pump?
Click to expand...

Yeah the crank inner groove will run the water pump and alternator. Basically this setup.

BPE-4730-b.jpg
 
I agree, not enough wrap on those pulleys. You usually want 1/2 at minimum up to 3/4. Thats going to do nothing but slip.
 
Tho mine doesn't have power steering yet. I run the A/C to the inner pulley and the water pump/alt on the outer pulley.
Using a 2 pulley alternator with belt on the outer.
I believe when I get ps it will run crank/ac/ps much like ESP47 photo.
Sorry best photo I got.

IMG_0004.JPG
 
The more belt engagement the better. I would say at least half the pulley coverage minimum. Any less and it could slip. Thats for all the pulleys. Lay a straight edge across the center of the pulley and it should meet belt on both sides. Yeah there will be some custom situations where this is not possible but its not an idea situation. If you cant get it to work out you may need to fab a bracket with an idler.
 
The way I read it, he's going to run a fan/alt/water pump belt on the inner groove, with the outer belt as shown, or did I read wrong ?
Bottom pulleys equal size .
Water pump is merely an idler/guide for the outer belt.
 
Last edited:
inertia said:
The way I read it, he's going to run a fan/alt/water pump belt on the inner groove, with the outer belt as shown, or did I read wrong ?
Bottom pulleys equal size .
Water pump is merely an idler/guide for the outer belt.
Click to expand...

Yeah that's correct. Thanks for simplifying it.
 
The only problem I see is if the outer and inner crank pulley grooves were different diameters. Then the belts would be traveling at different speeds and the one barely touching the water pump pulley would burn up pretty quickly. But it appears the inner and outer grooves are the same diameter.
 
Expect it to overheat with the tiny crank pulley. P/S might be a bit ratchety at low speeds.
 
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