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Discussion Starter · #1 ·
I got the 400 in the car and now i ran into the infamous Pontiac pulley alignment issue...the pulleys of water pump, alternator and ps pulley all match up. But the lower crank pulley dont match up with the water pump. It appears if the lower crank could go in further it would match but its in as far as it will go. Short off converting and switching everything will a wp spacer push out the wp pulley work?

Car is a 75 block
Pulleys came off my 69 block. So that appears to be the issue?

The wp is 4.5 for both 69 and 75 block so that cant be the problem.

On my 1969 400 b4 engine went bad never had pulley issues and these the same ones.

Finally only thing i changed on the 75 block was i installed a new Harmonic balancer.
 

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Pulleys came off my 69 block. So that appears to be the issue?

The wp is 4.5 for both 69 and 75 block so that cant be the problem.
Sure it can be the problem. Early production 69s had a short snout water pump and it sounds like that's the pulleys and brackets that you have for all your accessories. I bet if you have a way to actually measure, you'll find that your crank pulley is sticking out exactly 1/2 inch too far.

I ran into this exact same problem on my 69 when I upgraded the harmonic balancer to an SFI rated piece.

On early production 69s, the outer edge of the balancer has a chamfer so that the drive pulley on the crank can fit around the outside of the edge of the balancer. When you change balancers, most of them don't have that feature and you'll end up with the crank pulley being out a half inch too far.

In my case, I made spacers to move all the accessory drives forward just enough to get the belts to line up. It was a tough job. I made an alignment checking tool to help me get all the belt grooves in alignment with each other.

Bear
 

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Discussion Starter · #3 ·
Sure it can be the problem. Early production 69s had a short snout water pump and it sounds like that's the pulleys and brackets that you have for all your accessories. I bet if you have a way to actually measure, you'll find that your crank pulley is sticking out exactly 1/2 inch too far.

I ran into this exact same problem on my 69 when I upgraded the harmonic balancer to an SFI rated piece.

On early production 69s, the outer edge of the balancer has a chamfer so that the drive pulley on the crank can fit around the outside of the edge of the balancer. When you change balancers, most of them don't have that feature and you'll end up with the crank pulley being out a half inch too far.

In my case, I made spacers to move all the accessory drives forward just enough to get the belts to line up. It was a tough job. I made an alignment checking tool to help me get all the belt grooves in alignment with each other.

Bear
sounds like exactly what happen with mine. if my crank pulley would go in more then they would all match up.What did you do and use for spacers?
 

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sounds like exactly what happen with mine. if my crank pulley would go in more then they would all match up.What did you do and use for spacers?
I used a combination of things. I used steel plate behind the big bracket that mounts the power steering pump and the alternator, between that bracket and the head. For some of the other spots I use some thick wall tubing on the bolts in various places to move everything forward. It took a lot of time and I had to measure everything really precisely to get it all to work.
 

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I actually found some photos of how I did it. I hope this helps:

Automotive tire Vehicle brake Automotive lighting Motor vehicle Bicycle



Tire Wheel Vehicle Automotive tire Synthetic rubber



Tire Wheel Motor vehicle Automotive tire Tread



....and the alignment tool I made. The curved notches seat it and square it up with any one of the pulleys. I set it into one pulley first and make sure it's seated well, then lay the other end of the tool into a different pulley. If the bar sits in the center of it, then I know the two are aligned with each other. I always check alignment from both the 'top' and 'bottom' sides of each pulley to make sure that they aren't "canted" with respect to each other.

Automotive tire Automotive exterior Rim Bumper Automotive wheel system



Tire Wheel Automotive tire Motor vehicle Tread



Automotive tire Motor vehicle Automotive design Wheel Tread



Chair Windsor chair Motor vehicle Wood Machine tool


Tire Bicycle tire Automotive tire Motor vehicle Wheel
 

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1968 Solar red GTO
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I just switched to a 1 wire alternator, and it starts chirping above 4K rpm- the alternator (or pulley) is just a bit forward of the stock one- i can drive it, but it squeals above 4K when i get on it.

The alternator needs to go back just a bit
 

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I had the devil of a time with mine. Did you know that the factory parts book lists something like 3-4 different water pump pulleys for 69 A bodies, all because of the different pumps that were issued only for part of the model year?

Mine kept throwing or rolling belts until I finally got them lined up.

Bear
 

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I used a laser pointer for pulley alignment. I found a circular laser pointer, like a pen shape but shorter. I layed it in the pulley grove which self-centered it and then taped it in place. Rotating the pulley I could point it at any other pulley and see where the laser dot hit, made adjustments until it was centered in the pulley groove.
 

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I used a laser pointer for pulley alignment. I found a circular laser pointer, like a pen shape but shorter. I layed it in the pulley grove which self-centered it and then taped it in place. Rotating the pulley I could point it at any other pulley and see where the laser dot hit, made adjustments until it was centered in the pulley groove.
That's a great idea!
 

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Discussion Starter · #11 ·
Update

I ended up getting the belts to line uo but only because i happen to have a friend that had a different Pontiac pulley..one i had is 9799130xj for ny old 1969 Pontiac 400..since the new block is a 75 with 68 heads and m6 friend pulley came out of a 76 Pontiac and the numbers are
10004850yy for 75 76 Pontiacs. So now everything lines up.
 

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Cameo Ivory 1967
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I just switched to a 1 wire alternator, and it starts chirping above 4K rpm- the alternator (or pulley) is just a bit forward of the stock one- i can drive it, but it squeals above 4K when i get on it.

The alternator needs to go back just a bit
I have the same issue, but in my experience, that means a belt is too loose. Powermaster recomends that a belt be so tight, you cant turn the alternator with a 1/2 breaker bar on the pulley!

This is a quote from Holley Performance:

Our friends at Powermaster sell high output alternators that often use v-belt drives and these higher capacity alternators demand more power to turn. Powermaster’s recommendation for belt tension is that the belt is not tight enough unless you can begin to turn the engine with a socket and breaker bar turning clockwise on the alternator fan nut. That seems a bit excessive, but then a 140 amp alternator at full output will place a much greater load on the belt than the old 60-amp alternators from back in the day.

 

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I use a gates laser belt alignment tool. Designed for that job. On Gates web you can see various procedures for tightening different belts. But generally a new belt is set very tight, then after five minutes of break in idling the tension on the belt drops dramatically.
 

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I have the same issue, but in my experience, that means a belt is too loose. Powermaster recomends that a belt be so tight, you cant turn the alternator with a 1/2 breaker bar on the pulley!

This is a quote from Holley Performance:

Our friends at Powermaster sell high output alternators that often use v-belt drives and these higher capacity alternators demand more power to turn. Powermaster’s recommendation for belt tension is that the belt is not tight enough unless you can begin to turn the engine with a socket and breaker bar turning clockwise on the alternator fan nut. That seems a bit excessive, but then a 140 amp alternator at full output will place a much greater load on the belt than the old 60-amp alternators from back in the day.


That’s exactly what happened! Ive now adjusted it and its noise free!

Thank you for the input
 

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I use a gates laser belt alignment tool. Designed for that job. On Gates web you can see various procedures for tightening different belts. But generally a new belt is set very tight, then after five minutes of break in idling the tension on the belt drops dramatically.
Which tool do you use? The ones for v-belts that I found on the web just now were very expensive.
 

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I used a laser pointer for pulley alignment. I found a circular laser pointer, like a pen shape but shorter. I layed it in the pulley grove which self-centered it and then taped it in place. Rotating the pulley I could point it at any other pulley and see where the laser dot hit, made adjustments until it was centered in the pulley groove.
I agree, great idea. I borrowed your idea and used what I already had, a laser bore sight for sighting in firearms. It works great if you slip it into one pulley groove and rotate toward whatever you are trying to line up. Thanks for the good idea.
 

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I have the same issue, but in my experience, that means a belt is too loose. Powermaster recomends that a belt be so tight, you cant turn the alternator with a 1/2 breaker bar on the pulley!
No way would I ever run one that tight. :oops: It's possible to get the belts so tight that they put enough upward pressure on the crank to cause premature wear on the upper main bearing shell. I've done it. Never again.

Bear
 
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