V-belt pulleys

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pjc360

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I have a 320hp crate 360 magnum engine in my 91 half ton short bed four wheel drive truck.
The front of the engine had the la timing cover and la v-belt set up on it with a mechanical fuel pump.
I've struggled to get the belts to line up with the pulleys and I've come to the conclusion that I must have the wrong pulleys, my crankshaft pulley has 4 grooves and my water pump pulley has 2 grooves and the water pump pulleys grooves sit further up towords the radiator which seem to throw everything off.
From what I've seen the early to mid 70s small blocks that run with no a/c and no smog pump just power steering and alternator have a one groove water pump pulley that is deeper making the groove further back towords the engine.
Then the crankshaft pulley has 2 grooves.
The alternator runs around the water pump pulley and crankshaft pulley and then the power steering pump belt rides soley on the crankshaft pulley.
I'll post some pics below to show you guys what in dealing with, I'm thinking I'm going to need to hit up the scrap yards and find a early to mid 70s non a/c small block and take the pulleys off and then put them on my engine.
I've never seen a 4 groove crankshaft v-belt pulley on a small block mopar and I've never seen the two groove water pump pulley that's on my engine currently ether.

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The first picture shows how the power steering pump pulley doesn't line up with any of the crankshaft pulley grooves.
It sits between the groove that the alternator belt is supposed to ride on and the groove behind it.
Even though the power steering pump isn't bolted up in that picture I'm
Holding it where it would be once it's bolted up.
 
Double groove alternator and water pump pulleys typically came on vehicles with A/C.

If you didn't have A/C, the alternator and water pump pulleys were single groove...
 
IIRC, the pulley that is first shown by the OP is a per-1970 pulley, made for the older, iron water pump. The later deeper type that KK shows is needed and is for the longer snout on the Al pump that you have on your engine.

I don't know about the PS pump.
 
I have that alternator bracket that Krazykuda posted, and do I need the two groove crankshaft pulley or can I get away with using this 4 groove crankshaft pulley?
I was told once I have the correct water pump pulley the alternator will run on the groove closest to the engine on the crankshaft pulley and the power steering belt will run on the crankshaft pulley one groove ahead of where the alternator belt will be.
 
pjc360 said:
I have that alternator bracket that Krazykuda posted, and do I need the two groove crankshaft pulley or can I get away with using this 4 groove crankshaft pulley?
I was told once I have the correct water pump pulley the alternator will run on the groove closest to the engine on the crankshaft pulley and the power steering belt will run on the crankshaft pulley one groove ahead of where the alternator belt will be.
Click to expand...

You can use the 4 groove pulley if the grooves line up with the rest...
 
krazykuda said:
You can use the 4 groove pulley if the grooves line up with the rest...
Click to expand...

I went to one of the junk yards and found a early to mid 70s half ton power wagon truck with a 318 no a/c and no smog pump and pulled the water pump
Pulley and crankshaft pulley.
I'll post pics below of the pulleys I bought.
I think these are the correct pulleys for the set up I am trying to run the crankshaft pulley has two grooves and the water pump pulley has one groove and it sits back further by the water pump.

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The water pump pully looks right it should be about 3" deep, front to back. I would not be surpised if it lined up with either crank pulley.
 
The water pump pulley is correct.

It's hard to tell on the crank pulley with the angle of the picture...
 
krazykuda said:
The water pump pulley is correct.

It's hard to tell on the crank pulley with the angle of the picture...
Click to expand...

The crankshaft pulley should be correct because I pulled both pulleys off the same engine.
Which was a 318 I believe, guess it could have been a 360 too.
But it was in a early to mid 70s power wagon truck with no a/c and no smog pump.
I put the crankshaft pulley on my 360 and everything went fine there then I swapped water pump pulleys and then I put a brand new one groove pulley alternator on and the belt lined up perfectly with the water pump pulley.
I got the power steering pump back on the engine and realized I don't have a belt short enough for the power steering pump now since it will be running soley off of the crankshaft pulley now.
Anyone have a part number to the correct belt for the ps pump?
By lookin at where the pump sits when it's bolted to the engine the ps pulley seems to sit a tad bit behind the outter groove on the two grooved crankshaft pulley but I guess I'll see how it looks with a new belt on it.
 
pjc360 said:
Anyone have a part number to the correct belt for the ps pump?
Click to expand...

We just installed our belts a couple days ago:

Alt-WP-Crank belt = Gates 7470 (47 inches long)...

PS-Crank belt = Gates 7380 (38 inches long)....
 
Ok guys I'm back, I'm real close to having the v-belt set up figured out and straight but my power steering belt is going on cockeyed and I don't know why.
As you know I changed the crankshaft pulley and the water pump pulley to the correct pulleys for the v-belt set up with alternator and power steering.
My previous ps pump brackets were bent and tweeked from it being mounted wrong and from being really old.
So I bought brand new ps pump brackets and they arrived today so I swapped the brackets out and was excited thinking that was going to solve my crooked ps pump belt and it didn't sold it.
So I took some pictures to show you guys how the ps pump belt looks. I got frustrated and asked my wife to look at it and she thinks the ps pump pulley is on the ps pump crooked or cockeyed and that's what's causing it. But I'm
Not seeing that when I look at the pump and the pump pulley.
The alternator belt is perfectly straight and looks great, power steering not so much.
It looks time like the power steering pump pulley needs to come forward more to match the crankshaft pulley.
With where my ps pump pulley is sitting the ps pump belt is straight inline with the crankshaft pulley when I move the belt back a hair like right between the two grooves on the crankshaft pulley.
The pulley that's on my ps pump did come off of a Chevy Saginaw ps pump cause my original ps pump pulley was bent.
But the pulley looks identical to my original pulley I remember comparing them and noticing they were the same.
Anyways here's some pics below, please help this is so frustrating.

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It looks like the ps pulley is not parallel to the crank pulley... It's slightly cocked inward on the inside...
 
So what do I do? Pull out the pulley puller and push it on further or pull it out some?
 
krazykuda said:
Look to see why it's crooked.

Are the brackets ok? pulley shaft?
Click to expand...
Brackets are brand new. Thats why I listed saying I need help, I don't understand what's causing it.
I just installed brand new ps pump brackets.
 
pjc360 said:
Brackets are brand new. Thats why I listed saying I need help, I don't understand what's causing it.
I just installed brand new ps pump brackets.
Click to expand...

Is the shaft perpendicular to the pump?

Is the pulley perpendicular to the shaft?
 
I'm starting to wonder if the 360 magnum blocks are just different and things don't line up the way they do on la 318s and 360s.
I just don't get this issue its bizzar and I've been fighting with it for years now.
I finally get the right pulleys crankshaft and water pump cause I did have some strange pulleys on it a 4 groove crankshaft pulley, and a two groove water pump pulley where the grooves were up closer to the radiator.
I got brand new ps pump brackets online and put them on and the pump pulley isn't lining up with the crank pulley.
It just doesn't make sense to me
Here is the paper that came with the new brackets.

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My wife looked at it and said she thinks the pulley is on crooked on the pump.
But I don't see how or why it would be throwing the belt off so far
 
pjc360 said:
My wife looked at it and said she thinks the pulley is on crooked on the pump.
But I don't see how or why it would be throwing the belt off so far
Click to expand...

I am seeing the pulley a little crooked from the pictures myself...

If the pulley is crooked, it can throw the belts off, especially when you rev it up...
 
Look at the illustrations and the picture on the bracket instructions at the outer fastener of the PS pump body (the one closest to the frame rail). Notice that there is a nut or spacer between the back of the bracket and the body of the PS pump at the outer fastener. You are missing this spacer; put that in and I bet it will angle your pump properly to align with the crank pulley. You can just stack a few washers in there.....
 
nm9stheham said:
Look at the illustrations and the picture on the bracket instructions at the outer fastener of the PS pump body (the one closest to the frame rail). Notice that there is a nut or spacer between the back of the bracket and the body of the PS pump at the outer fastener. You are missing this spacer; put that in and I bet it will angle your pump properly to align with the crank pulley. You can just stack a few washers in there.....
Click to expand...

Yep, that could do it...
 
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