72 Olds Project

Okay, so I read you should be fine using your 350 brackets as long as you use them all on your 455. I have an issue here though. Am I missing a bracket? The diagrams are not very clear in the manual and it looks like another link goes to the pump bracket to the manifold bolt. I was thinking my alternator bracket hole at the bottom went on the manifold bolt. If I do that then it will not go on. Here are some pictures. Thanks.



You can see the monster gap in this picture. This is when I bolted everything up but left the hole on the manifold bold undone and the front one of course.

oldspackrat

Unknown-106.jpg?t=1306200546

MDchanic

It looks to me like you've got the correct lower alternator bracket in photos 1 and 3, but it is not attached in photo 2.

As in Scott's picture, the bracket should span the space between the frontmost exhaust manifold bolt and the hole in the front section of the 2-piece p/s pump bracket.

What is probably confusing you is the illustration in the parts manual of a smaller bracket that goes between exactly the same holes. That bracket is used in cars without A/C, but with p/s, which have the alternator on the opposite side. If you have both A/C and p/s, then the alternator is on the LH side, and the lower alternator bracket serves the purpose of stabilizing the p/s pump, which the smaller bracket would have to serve otherwise.

Did that make sense? I'm not sure.

- Eric

72 Olds Project

Thank you both and that does make sense Eric. Thanks for clearing up that other phantom bracket I was wondering about. The problem is though when I started I kept all the brackets together thinking i could just pop the 2 main ones back on. Well that lower one with the brace does not want to pop. LOL When I got everything together and thought I was set, I went to put the alternator in and found out the bracket was way too off for it to work. The pulleys would never line and the back brace was about a 1/2 inch deep into the body of the alternator. Once I took the bolt out that goes with the P/S bracket it would fit as it was supposed to, but of course left with that gap. So essentially I have everything and it should work though. I will look again tomorrow. Now I put a stud on the front manifold bolt. Is it supposed to have a nut then bracket then another nut? Or is the bracket supposed to be touching the manifold/header with no space between? Thanks again!

MDchanic

The part that attaches to the exhaust manifold just goes right against the manifold with no nut or spacer. The smaller bracket (for non-A/C cars) has 2 possible manifold holes in it - one for 350 and one for 455 - only one will work. I believe that the lower alternator bracket that replaces it has the same feature.

- Eric

72 Olds Project

That could be where I went wrong as I put a nut to hold the header on then tried the bracket with a nut holding it on. Thinking typical Chevy ways is wrong I know. I will try that after work and see if that helps taking that out. I actually think I saw a long bolt with a lock ring on it. That probably went to the front manifold bolt originally.

72 Olds Project

Okay, well I took the nut out and unfortunately still no luck. I included more photos. The 1st is just the bracket installed by itself. Then the next is when I add the alternator. As you can see, no way that bracket will fit. My next question is...did they use 2 different alternators? Maybe with using the older C heads I need to use the older alternator? Help please






In the pics you can see the bracket for the front of the Alternator is a good 1/2 inch away and its not straight. Like it has a curve to it. Both sides bolted fine though on the block and on the P/S bracket. Just when you go to put the alternator on it is all messed up and doesn't fit right.

MDchanic

Okay, I'm baffled.

There's only one hole that you can attach to the exhaust manifold bolt, and there's only one hole you can attach to the p/s bracket. The part only fits one way, and the parts manual says it fits both 350 and 455 (part #410760).

The alternator mounting points should be the same.

All I can say is that I wonder whether you've got the spacers to the p/s pump bracket right - if they are off, then the location of the front of the bracket will be off, and this alternator bracket will be off because it attaches to the p/s bracket.

- Eric

72 Olds Project

Me too Eric. LOL Thanks for trying to figure it out. Something is just not right in Olds land. I even looked at the second set of brackets and I have 2 of the lowers that are the same...just one has a big box cut out of it.
But like I said.....the bolts to the block and pump bracket fit perfect....but once you put the Alternator through the top bolt...its a no go. Way way off. Very very odd.
I will check the spacers, but the one I have was the original and the other I had to rig up a little, but even say an 1/8th of an inch wouldn't throw it all off that bad on one. I have a mechanic buddy coming over this weekend to figure it out. My shade tree is not working on this one

hamm36

I think for starters I would put the PS pump strait up. PS bracket attached to the block on the lowest part of the PS bracket there should be a 1/2", or more spacer in there, between the bracket and the block. Believe it or not that might help.

MDchanic

The pump sits at the same angle on my motor. It's the closest in position for when you've got new belts that haven't worn yet.

- Eric

72 Olds Project

Thanks. The spacer is on there. Its a little over a 1/2 inch one. I messed with it again tonight and no matter what I did I get the same results. Now I have a thick 1 inch round spacer that I shoved between the P/S bracket and the Alternator bracket. When I did that it made everything straight. Wonder if I should just go with that?

hotrodpc

It seems I read somewhere that a 350 water pump has a different dimension for some reason. Anyone know if its true or not, and if it will affect the way the brackets line up, or would it make a diffenece in the water pump pulley at all??

I too, have a 68 455 wo brackets or a harmonic balancer. It's my understanding I can use my balancer and brackets off of a complete 77 350 that I have, on the 68 455. Does this sound right to anyone else?

72 Olds Project

Now that is a VERY good question HotRod. Does anyone know if that matters? I know for a fact I am using a 455 water pump. Maybe it does not play well with 350 brackets?

72 Olds Project

Well I jumped on Autozone's webpage and it shows both the 350 and 455 use the same water pump. I guess that is not an issue, yet a good guess HotRod. The past 2 nights I went outside to mess with those brackets and they are wearing me down. LOL I may just use that big thick spacer I have and put it in between the two brackets. That spacer had to go somewhere.....just not sure where. The joys of messing with 2 different engines and not knowing what you have to start with.

J-(Chicago)

If everything lines up correctly with it like this:



Then I would just make a spacer to go in between the bracket gap.
The 455 has about a 1" taller deck height than the 350 did, and your 350 alternator adjustment bracket looks like the correct one.

72 Olds Project

Exactly what I was thinking J. I mean if it is known to have a 1" difference in the height of the heads, then perhaps that is the entire issue. I do not see how the 350 brackets that have shorter heads would fit exactly the same. I will take a pic tonight and show the spacer I had and put in its place. It looks a little funny, but it seems to fit

joe_padavano

Think about this for a second. The PS pump bracket bolts to the block. The alternator bracket bolts to the head. The head is 1" further away on a BBO than on an SBO. Of course there is a spacer that goes in there.

72 Olds Project

Just the fact though that the diagrams do not show any spacer....of course we are not stock anymore I just wonder where I got that spacer from honestly. Because those brackets all came off the 350 I had and they would not have needed said spacer. Maybe I just got lucky? Or maybe it did come from my Core 455 block? Who knows at this point. It just does not look like something the factory would come up with and use Pics later when I get home.

hotrodpc

I've still got my 77 350 all together up front and planned on taking lots of pics before I pull the front off. I'll see about taking some good close ups. Maybe it will help you out in orientation of the brackets, or maybe you're missing a spacer. We'll find out. Hopefully by this evening.

BTW, should I keep this 350 motor? I was thinking of scrapping it. Its a 77-80 block and smogger heads, so its the not so favorable mains. I just figured if I was going thru the expense of a 350 build, I'd rather do the older 350, and I don't want to use these choked up heads. I was just going to rob all I could off of it for my 68 455 and scrap it.

72 Olds Project

I really appreciate that HotRod. I thought I took good pics, but unfortunately I missed the most important ones it looks like.

Hmmmmmm the purist here will say keep it I am sure and you also may be able to sell it. Honestly I gave away my tired 350 and TH350 transmission. I am sure someone here would take it off your hands. The motor I had still ran but it was wore out. It actually got me halfway through NC (back home) after only 4 or 5 break downs It had 0 Oil Pressure when sitting at a light. haha I had a Pontiac 350 before and I did not like that motor at all. I knew when I got the Olds that I was not dropping 1 cent in that 350. Not to hurt people's feelings as I am sure a built 350 has some power, but mine was WAY underpowered. These cars to me are too heavy to have a small block. They are good for "economy" cruisers though and can see that side of the argument as well. To each his own

And to add....I am saying a small block of this era. Not some 2011 Corvette small block or something crazy like that. Don't want people to get all touchy and turn this into "The Baddest Small Block Ever" infomercial. haha

hotrodpc

I took some pics just now. Probably not enough, but I will take more as I pull it apart too. I tell you what, digital cams are so awesome. I wish I had this cam and computer techhology 15 years earlier when I was much younger. It would have saved me countless hours. I tell all my buds, a digital cam in your toolbox is just as important as your 3/8 ratchet. Take pics of things like wiring harnesses, pulleys, brackets and such. I also take pics of transmissions I build as I take them apart and I know most GM transmissions like the back of my hand, but when you start getting confused between trans models, year differences etc, its always nice to be able to go back and look at the pics for confirmation.

Yes, this is runs but is wore out too. Compression was low, it burnt oil and blew blue smoke like crazy. Who knows, I might just freshen it up with hone and rings, but still, I've got other projects like the 68 455 to invest time into. If this wasn't a windowed main motor, or smogger heads, I'd hold on to it with my life, but its not.

hotrodpc

Here is some pics of the Aleternator/PS Pump side. Notice the white arrow in the one pic. Its a spacer on the PS pump bracket. Its down low but I took the pic from up above.

72 Olds Project

I wish I would finally purchase a real camera, but the car takes all my spare money. I use my iPhone for all my pictures, though not perfect they work. You are not kidding about the convenience of picture and PC technology. Where was it years ago? It helps when searching for answers that's for sure.

It would be nice to have a backup motor for sure, but I dont know. Again you could go get another 455 and go that. I bought my core motor for $150. No telling what you will run into on that 350. That was my final decision on mine as to whether fix it or dump it. Mine was a smog motor too so not worth anything to most.

72 Olds Project

Can you also get a picture of your top alternator mount as well that goes to the intake and to the block? I notice people have a support bracket up there as well...which I do not have. Hmmmm?

hotrodpc

See if this helps. I just remembered something. I am not sure how mine was done. But originally, this was diesel motor in an 80 Truck. They converted to this gas engine. So I don't know if they used OEM gas 350 bracketry or if they transfered the 350 Diesel bracketry. So this could be different than some others, but I have noway of know what they used for sure.

72 Olds Project

That's what it interesting. Everyone's top bracket to me looks a little different than what I have. The bottom brackets you have are the same as mine. Including the support brace. Hmmmmmm. Thanks for putting those pics up.

joe_padavano

Be careful with interpreting those photos. The 1980 diesel (as well as all other SBOs that year) use brackets that will ONLY fit an SBO unless you use a spacer. Keep in mind that the BBO was discontinued after the 1976 model year. The dual-compatible brackets were used for a while, but the brackets that use the aluminum upper alternator mount are DEFINITELY SBO-only. Again, the difference is just the 1" of deck height, so the SBO brackets bolt to the BBO but the brackets that bolt to the head will not reach the brackets that bolt to the block, as you've found out. That's why you have to use a spacer between the lower alternator bracket and the PS pump bracket.

72 Olds Project

Thank you Joe. So my top bracket is a normie then I hope. Okay here are the pics I promised. Everything is still a little loose, but I did it so I could figure this mess out. Does that spacer really look like something GM would try to get away with on an engine? Ever seen anything like it?

MDchanic

I can't post an image grab from the parts manual right now, as I'm at work, using a PC ::ick::, but I've gone through the parts manual and feel at this juncture I should make this point:

There are eight parts listed for attaching the P/S pump and alternator to the V-8 engine on A/C-equipped cars from 1972, aside from fasteners.
They are:

• Power Steering -
  • Brace 410335
  • Bracket 398668
  • Link 562594
  • Spacer (front) 404353
  • Spacer (rear) 398917
• Alternator -
  • Bracket 560594
  • Brace, adjusting 410760
  • Link, adjusting 410352 -or- 410353

These parts all fit all V-8 engines and all body types, with occasional exceptions (such as Toros and X-cars) from '68 or '72 until '75, and the same part numbers are used for ALL V-8s, 350 or 455, except for the "adjusting Link," which is the bracket with the curved adjustment slot that holds the bottom of the alternator.

"Adjusting Link" part #410352 fits 350s (and all 1974s, which I think is a typo).
"Adjusting Link" part #410353 fits 455s.

I believe that this might answer your question (and might also mean I need to get another adjusting link for when I assemble my smallblock ).

- Eric

joe_padavano

OK, let me clarify my earlier post. ALL of the brackets pictured in this thread are NOT correct for a BBO. They are all late 1970s-up SBO-only brackets. The dual-compatible brackets used from 1968-1976 do not connect the alternator bracket to the PS pump bracket. For the A/C configuration, the alternator bracket is two part. One part bolts to the front of the head, the other is a large H-shaped bracket that straddles the valve cover and bolts to the back of the first bracket. One leg bolts to an intake manifold bolt that has a stud on the head. The other leg bolts to a head bolt that has a stud on the head.

This design does not touch or bolt to the PS pump bracket at all, so it works for both BBO and SBO. The SBO-only brackets shown in this thread will work on a BBO if you make a spacer as I discussed above.

joe_padavano

Just stumbled over this photo on the web. THESE are the correct driver's side alternator brackets for a BBO. They fit both BBO and SBO (dual compatible) and were used for 1968-1976.

J-(Chicago)

Mr. Padavano is on point here.
However, I believe the brackets in this picture were discontinued in 1970. 71-up 455's have the style 72 olds project is currently using. 68-70 are the only motors that I have seen have this "letter H" and letter C" style.
I have been wrong before, but from my experience, these are a 68-70 only thing.
I can take a picture of my 72 455 brackets for everyone tomorrow.

hotrodpc

Thanks for the info Joe. We're getting alot of info and some can be confusing. So to clarify your clarification, obviously my posted pics of the 350 brackets are wrong and not going to work on a BBO at all. So the tell tale sign, or to make it easy to know, you're saying if the lower alternator bracket bolts the PS bracket, then you know its SBO ONLY bracket set and not to use it on BBO??? I'm not suprised at all. I never get lucky like that.
And since we have all the bracket pics flying around this thread, yes, that woudl be great to see your brackets J-Chickago. At least then maybe I'll recognize them if and when I see them. Thanks

hotrodpc

BTW guys, I don't want to confuse this thread anymore than it is. But if anyone knows anyone needing some 67 425 Alternator and PS brackets, I have some. The PS pump can type is round so it won't work with the more modern shape PS tank.

MDchanic

I agree with J that the pictured brackets would work, but are not the brackets supplied by the factory for the '72-up cars.

The H-bracket type look like this installed:


The Newer type look like this:


I couldn't find any other views of the newer type brackets, but I'm sure others will post some.

The H-type look like this from other angles:




I couldn't find any views at all of the lower portions of any of the brackets.

- Eric

hotrodpc

Thanks for the pics. At least I'll have an idea of what they look like so if I see them, I know what to keep if I come across it.

72 Olds Project

Thank you for the pics as well! Wow such a big difference between the 2 types. I wish I had the originals and part of me is thinking about purchasing some if I find a good deal. Of course I had to miss the most recent huge swap meet in Charlotte

Run to Rund

Please see my posts in this thread for more info:
https://classicoldsmobile.com/forums/small-blocks/45495-olds-350-alternator-bracket-question.html#post374309