The Stovebolt Site Forums The Shop Area Engine Shop 292 alternator pulley alignment

What is the best solution to align the alternator pulley with the other pulleys on a 292? It is about an inch off from the harmonic balancer and water pump.

Thanks

I would use spacers.

Kevin - Can you take and post a picture of the misalignment?

Too far forward or too far back???

This might help.
Service manual

Thanks for all the help. I'll post a pic when I can. The alternator is too far back. I don't see where it has any adjustment features. I think the bracket is standard for a 1966 292 engine. It is stamped "3831195"

I shimmed mine out with a spacer and longer bolt

I see that, thanks. I could do that on top but not sure what to do on the bottom pivot bracket. I'm trying to go stock as much as possible, and my water pump pulley is stock, not so sure about harmonic balancer though. However, harmonic balancer and water pump pully are perfectly aligned, only the alternator is out of whack.

GM# 3831194 comes up in my search as the correct part number for the 292 lower alternator mounting bracket. Fits 1963-72 C-10 thru C-30's w/292 engines (not for AIR, 62 amp alternator or HD water pump equipped trucks). First pic below is a pic from a 1970 Chevy Truck Master Parts Book showing the design for C10 thru 60 6 cylinders reference.

Your number "3831195" didn't come up in my searches. Possibly a typo?

Could be someone swapped out the balancer and water pump and you may need to get a different lower mount bracket. The same period 230/250 lower alternator brackets (GM# 465826) puts the alternator over an inch farther forward, but has a rear bushing that can be moved to the rear (gap created forward would need a spacer or washers to fill) to allow for alignment of the alternator with your current pulleys in the new bracket.

A new 230/250 style bracket can be found from lots of various aftermarket sellers. A sample is pictured also below.

Before jumping in, please post a picture of what you currently have as that needs to be confirmed before chasing this rabbit.

Thanks for the info. I will get some pics up. I had a new harmonic balancer put on, and it lines up with the stock water pump pulley. But I'm missing out on something. But as you say it is wasted effort without some pics so you can see the situation.

Did everything line up before you bought the new balancer? If so, then something's installed backward or has been forgotten

I'm working on a re-built engine so I'm putting everything back on. But I looked back at my old pics, and should have brought this up before now, but the original balancer had 3 grooves. The engine came out of a C-60. But that does not account for why the water pump pulley lines up with the balancer I now have. But like Gdads51 says above, I got to get some pics.

I have attached some pics. Note that this is a mock-up - I could not find the bolts for the water pump pulley, so it is stuck on with duct tape, and slightly out of kilter, but I think it shows that it will line up with the balancer. (I've got to knock the rust off the front of the balancer and paint it - that is if I keep it. It came from Summit Racing and may not be what I need)

Seeing the casting number on your mount, it's likely an original lower mount being it's just one number off from the actual book listed part number. It's kinda how Chevy did their parts identification with casting numbers, but since they mostly stopped listing the casting numbers in the mid '60s and later parts books in the item description, it makes it a little hair pulling to try and confirm what you have.

Anyhow, seeing the pics of what you have, I think your harmonic balancer and water pump and pulleys are good for use as is. On the realignment of the alternator, you have a couple of options IMHO.

First is to swap the mount with something that will move your existing alternator forward to attain alignment as suggested before with different bracket and spacers.

A second possibility is to purchase a slightly different style alternator (see screen shot below) from this sample linked source. It would allow you to relocate the alternator forward using the existing lower mount, by placing the forward lower mount ear in front of the mount forward pivot ear. Then use a longer bolt with spacers/washers and nut to attach to the lower mount to align with the other pulleys.

In both these cases, you will also need to modify and/or add spacers to the upper mount adjusting swing arm too.

Just throwing stuff at the wall to see if something might help you out.

Thank you. That alt. realignment looks like it may be a good alternative.

I just wish I could find out how it is supposed to work. How did it work on a 292 C-10 originally with the 3831194 or the 3831195 bracket? That is what I want, i.e. the "stock parts", if at all possible. I don't know how to find that out. I looked thru all my service and parts manuals and could not find any help.

I may be wrong, but your alternator looks like a 10si unit to me. They have internal voltage regulators. GM started using them in 1969 Corvettes and in all GMC cars by 1973. Maybe the mounting scheme and dimensions of your 10si are different than what was used on your '65 truck???

Not sure how to help at the moment. Could be the engine coming from a C-60 with possibly a different alternator and pulley could be the fix you need. Won't know more about that thought until I can get another chance to dive through the parts books.

Currently pulling Grandpa duty, so it may be a day or so before I can offer more. In the meantime, perhaps others have some suggestions?

I appreciate your efforts and certainly don't let it interfere with Grandpa duty. I don't know if you watch the Jayhawker youtube videos, but they are pretty good, and he is the one that told me about the engine I got. So I just sent an email to him to see if he can help. He has a series of videos where he rebuilt a '66 292, and I have watched them very closely, and it appears that his alt. pulley sticks out farther than mine, but not sure So I am hoping he can help.

to use what you have. drill a hole back the distance forward in the lower mounting bracket. Or use an adjustable mounting bracket.
I have one here that is slotted to match block(s).
Shim the upper bracket out to match the other pulleys. It looks like your ALT is close to the frame in the pic.

Just from the pics.

10-4 I don't have the water pump pulley bolted on for the pic so it looks kind of out of whack but it actually lines up pretty good. I appreciate your input I am considering all options

The simple, easy fix will be to put a 2-groove pulley on the alternator. Alternators DO NOT have woodruff keys in the rotor shaft- - - -the pulley is a simple friction fit. Use a 1/2" drive impact wrench to remove the single sheave pulley and replace it with a 2 sheave item. Lots of them are available on Ebay.

www.ebay.com/itm/134152116481?

www.ebay.com/itm/273276191786?

Jerry

I had a similar problem. I made a new mount to move it forward and clear my 7.5" damper. It was easier than it looks.

Thanks guys, really appreciate all the help. I'll let you know how I resolve

The two groove alternator pulls will be the fast fix for it. Damperdudes.net lists 6 different balancers for the 292, each with different pulley arrangements.