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Discussion Starter #1
Hello Boys:buhbye:
The aluminum crank pully on my 406SB just doesn't line up with the PWR steer pump pully. The stock pump mounting brackets, pully and pump are correct for my year and not damaged in any way. I need the crank pully shimmed out 3/16" (or so) for the belt to run true. Would fabricating a proper spacer (not just a washer) between the ballancer & pully harm anything or cause ballance problems? I know the water pump pully and alternator would have to be shimmed the same, but that's the easy part.
Eddie

P.S. I did measure the harmonic ballancer and it's the same thickness as previous.
 

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Are you going to shim the crank pulley, water pump pulley, alt pulley out to match the PS pulley? Wouldn't it be easier to move the pump back? Maybe I misread your question.
 

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Discussion Starter #3
Are you going to shim the crank pulley, water pump pulley, alt pulley out to match the PS pulley? Wouldn't it be easier to move the pump back? Maybe I misread your question.
And how would you move the pump back? Wouldn't purchasing all new pump brackets be necessary? It would be numerous hit or miss purchases to do so not knowing which would work.
I want to shim the ballancer pully out 3/16" so that it matches the PWR steer pump pully without any strength/ballance/etc issues.
Your thoughts???
Eddie
 

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I was thinking you could move the pump back with spacers on the three mounting screws however I can understand that there may be limited clearance there. Summit sells water pump pulley spacer kits and ,if I'm not mistaken, crank pulley shim kits. Not sure what you might do with the alternator.
 

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Discussion Starter #5
I was thinking you could move the pump back with spacers on the three mounting screws .
:cheers: Thanks for your response, but the original SB pump bracket is a one piece unit that bolts to the block and cannot be shimmed or modified rearward.
The search for an answer continues....:D
Eddie
 

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First make sure you have the correct water pump. There's a misconception that all short water pumps are the same. This isn't true. A standard short water pump has a block to hub dimension of 5 5/8 inch. This was used on Chevrolet passenger cars ( 55-68) and corvettes (69-70). 1971 - 1982 Corvettes used a short water pump with a dimension of 5 13/16 inch from block to hub. If you are using a pump for a 69 - 70 the block to hub distance will be 3/16 inch too short or, looking at it another way, your accessories will be 3/16 inch too far out. Now, given all that, its possible that the crank pulley you have is made for a 69-70 water pump which would cause you the same problem. I would check the dimensions of pulley suppliers to see if there is a pulley with the correct block to hub dimensions. Here's a link to Edelbrocks website that gives dimensions. Good luck.

http://www.edelbrock.com/automotive_new/mc/water_pumps/high_perf.shtml
 

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Discussion Starter #7
First make sure you have the correct water pump. There's a misconception that all short water pumps are the same.
http://www.edelbrock.com/automotive_new/mc/water_pumps/high_perf.shtml
Thanks for the info Vettefixer. Things are never "easy" with any project I take on. :thud: The water pump pully and the crank pully line up perfect with each other, so I think I will start looking into billet/aftermarket PWR steer pump brackets. I racked my brain studying the original steer pump bracket and it can not be modified to fit any closer to the block.
This is my biggest sumbling block to getting my car back on the road after nearly two yrs...ARRGGGGG...:crazy:
Eddie
 

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I racked my brain studying the original steer pump bracket and it can not be modified to fit any closer to the block.
If you have clearance to the mounting bracket behind your PS pulley, you should be able to put spacers on the three bolts that mount the pump to the bracket (not the bracket to engine). Just a thought.
 

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Being that everthing else is correct-could you have the wrong PS pump? Wrong PS pulley?They make different pulleys.Can you move the pulley on the PS shaft?If you cant move it can you modify and move it,3/16 isnt much?
 

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I just set my Damper in or out for the correct pulley alignment. You don't have to have the damper seated flush with the crank throw. All the damper shaft has to do is be in far enough for the pulleys to align and the timing cover seal to seal.
 

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Discussion Starter #11
I just set my Damper in or out for the correct pulley alignment.
If the ballancer is not seated on the crank throw and doesn't move while running...why not try that?? After all...it's only about 3/16" or less.
Thanks George
Eddie
 

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I set the damper with the puller/installer tools. Don't you have a threaded crank? You install the big center bolt and washer so the Damper won't come off
 

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If the ballancer is not seated on the crank throw and doesn't move while running...why not try that?? After all...it's only about 3/16" or less.
Thanks George
Eddie
The harmonic balancer bolt will keep getting loose and if you tighten it the balancer will go back in.If you want to do that then make a washer type shim to go between the balancer snout and the crank where the balancer bottoms out.I wouldnt leave the balancer bolt loose.
 

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I wouldnt leave the balancer bolt loose.
:agree: The balancer retains the lower timing chain pulley also and it's just a matter of time before the bolt falls out and perhaps a little more time before the balancer comes off:surprised
 

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Go to the hardware store and to the Hillman section (all the little cardboard drawers)and look for machine shims.They should have a 1.250 X 1.750.Stack a couple and it should work.
 

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I just set my Damper in or out for the correct pulley alignment. You don't have to have the damper seated flush with the crank throw. All the damper shaft has to do is be in far enough for the pulleys to align and the timing cover seal to seal.
Could that be why your crank cracked?
 

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Could that be why your crank cracked?
:huh: You are very confused!

I've had really good results with 4340 cranks no matter where I install the damper. The only crank that i ever broke in a chevy V-8 was the results of a mechanic cutting corners during balancing and clearancing the rods to cam. When the rear most main bearing was no longer there to support the 7 and 8 pistons and I floored it, the crank rear most throw broke off

The damper is fine and running on my 434 With the correct pulley alignment

When you get about 16 year of experience and not just 16 years of age you too will have some experience knowledge. My advice to you if you like working on motors is get on with a quality race shop or better yet a team shop and then be teaching us older guys all the new tricks.

I go to allot of world class road racing evens and I wonder how or where do all these young mechanics and techs come from? Most of them can't even speak english and they are from all over Europe.
 

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Not confused

I was just thinking pulling the crank out to align it could let it wobble a bit.
Aftermarket dampers are so tight that you sometime have trouble even getting them on far enough.

The damper crank hole must be 2 1/2 - 3 inches long of machined surface so a 1/4 inch in or out is not going to wobble
 

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Discussion Starter #20
Replies to all:
First of all...thanks for all your replies guys:cheers:
I know not to run the ballancer without the retaining bolt torqued to spec. :lookinup:
Didn't know the ballancer could be pulled out a bit to line up pullies...I will do that to solve my pully alignment problem.
Someone mentioned machine shims to shim the ballancer out or the crank pully out. THAT answers my question from the original post that it can be done...but I will go a different direction by moving the ballancer.
Thanks again to all
Eddie
 
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