Alternator Bracket Problem PartII

[Gramp'sGold70K20]

First, I would like to thank everyone for the posts on my original thread.
http://67-72chevytrucks.com/vboard/s....php3?t=164373

I'm still running into problems though. I removed the harmonic balancer because there was a little wobble and thought it might not have been pressed on all the way. I was thinking that a combination of pulley alignment and wobble caused one of the bolts on my alternator bracket to shear. Apparently, all my belts are slightly off center and I hadn't noticed it.

With a new balancer, my lower pulley is still off slightly. What do I need to do? From the pictures I posted can you tell me If I need to use a little more muscle to press that thing on or what? With the harmonic balancer installer I used it went on smoothly and stopped right where I thought it would. Does it need to go on more? Any suggestions?

[jhow66]

What kind of alt. brackets are you using? Photos?

[Gramp'sGold70K20]

This isn't mine, but it looks the same. I have a short water pump too.

[jhow66]

Just use spacers behind the bracket until it lines up. Does lower pulley line up with pulley on water pump. (Power steering looks like it lines up.)

[Gramp'sGold70K20]

I did just that with washers and was advised against doing that unless I fabricate a spacer so the entire bracket sits flush against the head. The original post goes into pretty good detail about that. Maybe my eyes are playing tricks on me, but it looks like the lower pulley is a little less than 1/8" too far forward. Same on the water pump.

[jhow66]

I have used spacers before with no problems. It sounds to me like the bolt just loosen and broke from the shake. Try blue loctite on the bolts. If you notice the space between bolt holes in the bracket do not touch the block so a spacer will work as good as a plate.

[SK1970]

Thats why I put a serpetine system from an 1989 Chevy 1500 on my motor it is alot less headache everything lines right up .

[Gramp'sGold70K20]

I may have to resort to that type of fix. Thanks for the on the loctite advise. That certainly may have caused the problem. From the picture can you tell if the balancer is on all the way?

[GMC AMI]

Originally Posted by Gramp'sGold70K20

I may have to resort to that type of fix. Thanks for the on the loctite advise. That certainly may have caused the problem. From the picture can you tell if the balancer is on all the way?

If it was on any further you would not be able to see the timing mark scribed line.

[55454]

I have been dealing with 69-72 since 81 (I Know 67-68) and I have never seen a pully like that with the factory alt set up. I mentioned this on the other post. If you could measure or have someone measure the distance from the balancer to the timing chain cover and see if yours is correct. Also if you need a pic of the correct pully pm your e-mail. If you need help you can call me I can send you the correct pully if you want to try it, I spent an hour on the last post and would like to see this fixed, thats all I can do, but cant help anymore by posting. I am can send the pully for shipping and you can try it and ship it back. Tell what to do.

Thanks Tommy

EDIT: PS not trying to be smart just trying to get it fixed for you.

[55454]

The p/s needs to run in the third position, a/c second and alt first. In the other post I noted in 67 and early 68 with power assit they had four positions, with no pully in the second positon. I believe this was done because the compressor was positioned differently but I am not positive. If you want this fixed check the balancer position and then get the correct lower pully for that set-up, I am more than willing to send you the pully for trail or call you.

Tommy

[Fred T]

Pulley spacing should be 2.0" between the centers of the inner and outer pulleys. Here's pics of the "correct" pulleys.

[55454]

Fred,

I could be wrong, but those are for the 67-68 and 67-69 GMC. with a/c,p/s and alt.
That is the four position pulley I have been talking about, the alt and a/c brackets are different in the 67-68 chevy p/u. I believe gramps needs the 69-72 chevy three pully set up to match the Alt. bracket, this pully also fits flat against the balancer. I am only trying to help and I could be wrong. I have pics of the complete set-ups if needed. I will ask huggercst to post a pic.

Thanks Tommy

[HuggerCST]

Looking at the pics, my guess is that you have the wrong lower pulley. I think 67-69 used the pulley that Fred posted, and 70-72 used 3 groove stamped steel, but I may be wrong. I don't think they will interchange with each other though. Here is a pic of a 69 a/c setup that I have for sale if that helps any. If you need a pic of the lower pulley I can do that, but I think it's the same as Fred's above. 67 & 68 used a cast 3 groove water pump pulley. In 69 GM changed the alternator brackets to the type pictured above, and went to a stamped steel 3 groove water pump pulley. In 70 they went to different(stamped steel) 2 groove water pump and 3 groove crank pulleys, a different offset on the PS pulley,(more inset), and changed a/c brackets. In '72 the upper alt bracket changed to have more arch. This is what I've gathered over the past few years, and have pics of some of the differences, but I don't claim to be an expert, especially with GMC & chevy differences, so if I'm wrong, someone straighten me out.

[mrein3]

Originally Posted by HuggerCST

Looking at the pics, my guess is that you have the wrong lower pulley. I think 67-69 used the pulley that Fred posted, and 70-72 used 3 groove stamped steel, but I may be wrong. I don't think they will interchange with each other though. Here is a pic of a 69 a/c setup that I have for sale if that helps any. If you need a pic of the lower pulley I can do that, but I think it's the same as Fred's above. 67 & 68 used a cast 3 groove water pump pulley. In 69 GM changed the alternator brackets to the type pictured above, and went to a stamped steel 3 groove water pump pulley. In 70 they went to different(stamped steel) 2 groove water pump and 3 groove crank pulleys, a different offset on the PS pulley,(more inset), and changed a/c brackets. In '72 the upper alt bracket changed to have more arch. This is what I've gathered over the past few years, and have pics of some of the differences, but I don't claim to be an expert, so if I'm wrong, someone straighten me out.

Hugger,
I don't want to step in front of Gramp'sGold70K20 but if he doesn't want to buy that lower pully I would be interested in buying it.
However I'm not sure what I need.
Right now I have a wobbling 4-groove set-up. I have ps and I have all the brackets to add AC, I just didn't get to the AC yet.

My truck is a mutt. I have something from every year but '67 so I can't tell you what I really need. I believe the AC brackets I have are the later style. The PS can't be correct because you can't see in the reservoir because the alternator bracket is in the way. However I'm so tired of calling for a ride with an almost overheated, alternator bracket bolt sheared engine that I'm willing to just try that pully.

If Gramp'sGold70K20 doesn't want it.
And you're selling it seperate from the rest of the AC system.

[HuggerCST]

Originally Posted by mrein3

Hugger,
I don't want to step in front of Gramp'sGold70K20 but if he doesn't want to buy that lower pully I would be interested in buying it.
However I'm not sure what I need.
Right now I have a wobbling 4-groove set-up. I have ps and I have all the brackets to add AC, I just didn't get to the AC yet.

My truck is a mutt. I have something from every year but '67 so I can't tell you what I really need. I believe the AC brackets I have are the later style. The PS can't be correct because you can't see in the reservoir because the alternator bracket is in the way. However I'm so tired of calling for a ride with an almost overheated, alternator bracket bolt sheared engine that I'm willing to just try that pully.

If Gramp'sGold70K20 doesn't want it.
And you're selling it seperate from the rest of the AC system.

mrein3- I would rather sell as a package deal, but may split it up. If I am correct in the above post, then the lower pulley that I have(like Fred's), will not work with your A/C brackets anyway. But, I could be wrong.

[Fred T]

So they changed pulleys in 70. Dang. Still, looking at the picture the crank pulley doesn't match the p/s. Best solution, if sticking with v-belts, is to measure from a flat surface on the face of the engine to the pulleys. I usually use a pair of steel scales. A heavy one that is long enough to lay across the face of the p/s and alt pulleys, to get a distance to the block. What you need to end up with is distances from the face of the balancer to the center of the v-grooves so you can get the right pulleys for the crank. You also might be able to shim the appliances out to match the crank pulleys, but that opens up another can of worms.

[pjmoreland]

A few days ago I was driving down the road and my truck started to make a whining noise. I pulled over immediately, thinking my transmission had taken a dump. As I got out of the truck I could tell the noise was coming from the engine compartment, so I opened up the hood and what do you know, the inner alternator bracket mounting bolt was backed all the way out of the head and was just dangling there from the bracket. Needless to say, I immediately thought about you Fred T and mrein who have both struggled with this issue. I guess I'll clean the threads out and throw some Loctite on there.

[PICKMUP]

Way too much info for me to sort out, but I notice a slight mis-allignment in most of our systems. If it is not throwing belts, I don't worry about it. Bolt shearing can be caused by the threads & shoulder of the bolts lining up with the edge of the bracket where it meets the head.
Just to add a little more confusion to this subject, there are three different PS pulleys depending on which of the year/bracket types you are running. When all else fails...go get a complete matching set of everything off the same engine...no mutts.

[Gramp'sGold70K20]

All of you are great for helping me get my truck up and running properly again! I am going to find a 3 groove lower crank pulley tomorrow. I double checked my harmonic balancer and made sure it was pressed on all the way. It measures 1 15/16 " from the back of the timing chain cover to the front of the balancer. I'll measure things out like FredT spoke about. Thank you FredT. Hopefully the pulley will solve the problem. Thanks for the info regarding the power steering pump too. I am hoping it will line up with the new pulley. I will post some pictures after I get that lower pulley in place and see what you think.

SKY1970, do you have a picture of your setup from that 1989 1500? I would love to see it. I want to do this first, but later on down the road I want to convert to the serpentine system.

[HuggerCST]

Originally Posted by PICKMUP

Way too much info for me to sort out, but I notice a slight mis-allignment in most of our systems. If it is not throwing belts, I don't worry about it. Bolt shearing can be caused by the threads & shoulder of the bolts lining up with the edge of the bracket where it meets the head.
Just to add a little more confusion to this subject, there are three different PS pulleys depending on which of the year/bracket types you are running. When all else fails...go get a complete matching set of everything off the same engine...no mutts.

AH, so there are three different PS pulleys. I thought that there might be, but wasn't sure. Well, I know that the one on the right is like the one on my 69 setup. I know that there are also 3 different styles of PS pump mounts also, but I thought that they all interchanged. But, if there are three different offset PS pulleys, then there are either three different lower pulleys, or differences in the PS brackets. confusing.