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Of course you will have to remove the fan assembly, and all of the belts to install the crank to wp belt. With the wp pulley in your hand, put the belt on the on the rear crank pulley groove and rear wp pulley groove and work the wp pulley onto the water pump studs.
Report back if you need help.
And be prepared for a wrestling match getting the pulley holes to line up with the water pump studs while wrestling a belt with little elasticity. Once on, the belt will have some slack to be taken up with the idler pulley. Both the mounting bolt and pivot nut for the idler need to be loosened; press the pulley against the belt by hand to slightly deflect it and snug the slotted pivot nut to hold the position. Then tighten the mounting bolt and recheck the pivot nut.
Lord help me, I've got it apart.
There's not much room between the crank pulleys and the shroud. I had to wrestle the PS belt off.
It was so loose that I was able to just pull the water pump pulley off with it still attached and didn't have to loosen the PS pump at all.
Doubt I'll be so lucky as to be able to put it back on that way.
The sides feel very slick so I'm guessing it's glazed. I'm going to buy a new one, I guess one same size and one a 1/2 inch smaller to see what I can do. I haven't been able to contort myself around to see how much adjustment is left on the PS pump yet.
Just got home from the store with a 3 ton floor jack so now we're cooking.
Which P.S. belt you select will be determined by the final location of the pumps dip stick / cap.
Or in laymans terms: How the hell do I get the PS cap out?
I used a Gates 7440. It was easy to get on. The 7435 fit, but it put the PS dip stick under the alt bracket and i had to spin the pulleys to get it on. The 7445 was so loose I could not adjust it. I am considering trying a 9440 because I have a 140 amp alternator on now and I still get slippage when cold.
Last edited by 2mnyvets; Jan 31, 2021 at 01:43 PM.
Okay, the Gates 7315 absolutely will not fit. I need something that is several inches bigger. With it wrapped around the crank pulley it just barely goes over the water pump studs. No way is it going to fit over the top pulley.
In this picture I had to pull hard just to get it over the studs.
Also, I jacked the car up and climbed underneath. I don't see hide nor hair of the bottom PS bolt. I think I can barely see it when looking down from above.
And finally, I can't get my wrenches in to loosen the pivot bolt on the idler pulley. There's just no room.
Okay, the Gates 7315 absolutely will not fit. I need something that is several inches bigger. With it wrapped around the crank pulley it just barely goes over the water pump studs. No way is it going to fit over the top pulley.
In this picture I had to pull hard just to get it over the studs.
Also, I jacked the car up and climbed underneath. I don't see hide nor hair of the bottom PS bolt. I think I can barely see it when looking down from above.
And finally, I can't get my wrenches in to loosen the pivot bolt on the idler pulley. There's just no room.
Keep looking, on the PS there's 1 bolt on the bottom in the front and a nut on the rear, plus the adjustment nut.
On the bottom idler pulley bolt, you have to go through one of the pulley holes with a socket to loosen and tighten it. You have to have the idler pulley pulled out before you can install the belt over the crank pulley.
Last edited by 71 Green 454; Jan 31, 2021 at 02:23 PM.
Okay, I measured the circumference of the valleys of both pulleys together and had my son (the human calculator) do some math. Looks like I need a belt with about a 36.6" OD in order to fit.
The Gates 7315 is about 32.5" OD.
I actually got the idler with an open end wrench, reaching over from the far side of the car, and using a much better light source.
I think I found the PS bolts, had to go further under than I thought to see them.
I have no idea what I'm looking at in your pictures.
Remember, when it comes to cars, I'm retarded.
Yes, you can use an open end wrench to loosen the idler pulley adjustment nut, but there is also a lower bolt for the swivel.
The first photo shown is the Lower PS bracket where the rear nut is located, and the second photo is the Lower PS bracket where the front bolt is located for the PS to swivel.
I can get a Gates 7315 belt on my BB but it's super tight. I use a Gates 7320 for the crank to water pump belt.
*If the crank to water pump belt goes on easy, then it's probably going to be too loose. I wouldn't go any larger than a Gates 7320.
Last edited by 71 Green 454; Jan 31, 2021 at 03:58 PM.
Okay, I measured the circumference of the valleys of both pulleys together and had my son (the human calculator) do some math. Looks like I need a belt with about a 36.6" OD in order to fit.
The Gates 7315 is about 32.5" OD.
Are you replacing your PS belt? If you are, measure it and then cut it from a loop to a straight piece. Put you WP pulley on with one bolt. Wrap the cut piece around the pulleys and mark where the cut end meets the extra length. Measure that and it should be close to you needed length.
Okay, I measured the circumference of the valleys of both pulleys together and had my son (the human calculator) do some math. Looks like I need a belt with about a 36.6" OD in order to fit.
The Gates 7315 is about 32.5" OD.
I don't like the sound of that. And you mention the engine and possibly the bottom pulley could be from a truck. Everything thing else looks like factory 427/454 vette pulleys.
Why don't you go check the diameter of the bottom pulley? And I'll go check mine. It's possible a truck could use a different pulley ....
Update. You should have BB 2 groove pulley # 3921923 according to Paragon and it should be 6-3/4" diameter. There are some larger pulleys out there, especially on trucks, and since someone here suspected you grooves may not line up well, I think it would be good to check.
Look at the engine in post #8 and you can clearly see the 6-3/4" crank pulley and the much larger 8" harmonic balancer.
A police car is exactly the kind of vehicle that would have a bigger crank pulley.. And your PS belt number says it is 1.7" longer that greens LS5 belt and should not be even close to fitting.
Last edited by leigh1322; Jan 31, 2021 at 05:57 PM.
For your son: I decided to try and calculate the length too. I used a 5.5" WP pulley and a 6.75" Crank Pulley. I found these on the internet. I measure (approximated) the CL to CL distance at 7.375" to 7.625". The belt sits about .1" deep in the pulley so I subtracted .2 from the diameter. I used half the circumference (180 degree wrap) for each pulley and twice the centerline length. I came up with 33.35 OD.
Two other things. As I was searching for pulley diameters, it appears that 74 and later vettes use a 7.25" pulley and there appears to be 2 different big blocks. I don't know if the CL distance is the same on them.
I think these methods should get you close to sizing your belt.
Well, a 7320 was TOO small, and a 7340 was TOO big. So I've got a 7330 on order to pick up tomorrow.
I knew I should have just paid a shop $180 to do this right the first tine.
Well, a 7320 was TOO small, and a 7340 was TOO big. So I've got a 7330 on order to pick up tomorrow.
I knew I should have just paid a shop $180 to do this right the first tine.
But think about all the familiarity you are getting with the belt and pulley system! Priceless.
BTW, I find the lower idler bolt is easy to reach with a socket and 3.5" extension through a hole in the idler wheel itself. As I recall, the upper bolt doesn't align with a wheel hole, so open-end wrench is the only option.
