Why does my alternator sit right against the flange on the valve cover? There is a small boss that hits. I know it's not original but I don't see why this should happen. The bracket and spacers look right. I suppose I can just stick a washer between the mount and the bracket but that's kinda dirtbag. Any thoughts?

anytine you change one thing,it will affect another.use a washer or use the correct alternator

Terry, is the small boss supposed to be there? Or is the back housing supposd to be oriented differently? Thanks.

My date correct alt has a boss right there. It's a little different shape though. It does come very close to the cover. Just barely touches it. My brackets are all original.

here is a pic of the correct alternator back.

Mine is different than that. It's interally regulated. They aren't all the same... I'll get a picture...

See how the wiring plug is on the side?

67 to 69 firebirds did not come with internally regulated alternators.when you change one thing,you usually have to change other things

Ok now Terry. You caught me wrong now I catch you! Some 69's did have internal regs. Mine does and so does Vikki's car. Same assembly line, same month. AC cars. As you can see, the original wiring harness is even different.

Yep, the '69 400 equipment description calls for a standard "Integrated Circuit Voltage Regulator". UPC Code is K96 on the order sheet, 55 amp self regulating, available on V-8 only for $26.33 and standard on all Firebird 400 along with the R59 battery. Which is fine with me because I always hated voltage regulators. That along with points and ballast resistors put a lot of cars on the side of the road.
DJ

i thought only the trans am was the only exception and maybe the 400 cars.none of the standard 67 to 69 firebirds i have ever seen came that way

Way back when no one wanted firebirds, it seems that they were all clocked @ 12 o'clock, and all replacments--GM or aftermarket-alternators-were clocked @ 3 o'clock. The problem with clocking new parts is that they are often marked to show signs of fastener removal, voiding the warranry. That makes it a safe guess as to the reason why the 3 o'clock register--standared clocking on 2nd gen +--has now become "industry standard." I cannot tell, but it looks as if both alternators in the picture are clocked @ 3.

Unlike other people who don't mind coming off as most insluting, I add a disclaimer that I realise that some folks might not know what clocking means. I point out what clocking means because I realise that such configuration may not be common knowledge not because I'm an @$$hole and I view you as an idiot.

Clocking is the way the outer housings register. Remove the 4 long bolts that hold the housing together. Without taking the alternator apart rotate it one set of bolt holes. Based in the angle of the picture, it's hard to tell, but it looks if the back housing was rotated counterclockwise (looking from the back) one set of bolt holes, it would solve the problem.

Of course you have to make sure that there won't be a wiring interface problem.

Another factor that comes into play is that the mounting bosses on the alternator brackets can show signifigant wear. ALso,To judge how wear comes into play, eyeball the belt alignment. If it looks like whatever amount of spacing would offere better alternator alignment, the wear factor is also playing a role.

The problem could be that your fan belt is too big. A correct, or smaller, diameter one might move the boss enough to make it a 'non factor'.

not sure when that was....but I bought my first Firebird (a 68 350 coupe) as a used car in 1969, it was still under warranty....I loved the styling ,fell in love with it as I saw it for the first time.... but of course , I have exceptional taste....

Thank you all for your input. It does appear to be clocked correctly, the wires line up like they belong there. If it was rotated counterclockwise, the feed wires on the side would be right under the radiator hose.
DJ

My convertible came from the factory internally regulated. Have the dimples on the firewall to prove it. The cammer has a external reg.

Jim's on the right track, the belt is to big or stretched out. The alt should sit a little higher.

I had the exact same problem with my 69 400 cvt, which had an replacement alternator (internally regulated) when I bought it. The dimple was rubbing on the valve cover, not much but it didn't look right. When I finally got hold of a numbers correct alternator for the car, I found out that it had a different orientation (12 o clock), even though I used the same belt. Was a while back but I do seem to recall that numbers correct alternator had a slightly larger pulley. Here's how it looked installed.

http://www.frojdh.com/bilder/main.php/view/bird/misc/alternator_inplace.jpg?g2_imageViewsIndex=1

Goran,
Did that put the side wiring connect on the bottom? As short as your belt is in that picture my boss wouldn't hit either. My belt is longer. I probably have too long a belt.

Jim,
Again, this was a couple of years ago, so I don't remember the exact location, but as I recall both connectors (alternator main wire and the plastic thingy) was around 10 or 11 o clock on the back of the alternator.

Thanks. I would like to see a picture of the back of the correct one.

Searched my albums, and found a pic of the back. This is not my car, but it should be 100 percent original (I know the owner, and used his car as a reference when rebuilding my own 69). Looking at the connectors, it seems my memory wasn't all that good...

OK That looks about 180 degrees off from mine. I don't like how the main positive connect is so close to the valve cover. Looks problematic with adjustment. Original position or not, I'm not going to 'clock it' to get into that position. The way I have it would be better IMO.

Mine is installed the same way, but is rotated about 90 degrees clockwise (from the rear). The field wire connector is on top, and the main tap is clear of all obstructions.

It is my understanding that the positive connection which is supposed to have the plastic red cap on it, is supposed to be on top as Vikki is stating. My original alt was like that, then when I switched to an internal regulated alt. my positive connection was at the bottom near the valve cover.

As Jim said, having the positive connection at the bottom near the valve cover can cause some issues. At one time mine was so close I could not install the red cap and sure enough it was so close that the positive wire was arching accross to the valve cover.

I was told that you could rotate the two peices and bring the positive connection up to the top as they are supposed to be. Bascially re-clocking as Amervo talks about above. This solves all the problems. In addition the red cap will install and everything will look as it should...

Speaking of this same topic. Does anyone have an old correct fan/pulley for an alt.? I recently replaced my alt. and the new ones have a solid disc type thing vs. a fan blade look. I'd like to buy the correct fan/pulley if someone has one...

The extra-clean, not origional, car that's pictured is clocked, I think 2 steps too far. That's an accident waiting to happen. The factory did some chitty stuff on the cars, but they would never had sent a vehicle out with an always hot, 10 guage wire resting on a metal ground. Also, it's not the correct p/s cap. Then again, they may have used more than one style because they will use anything laying around the shop when bulidin a car. (Not knocking the car. The point is that this more than ovious incorrect has somehow become the benchmark for others to follow. I'm not big on trying to get a car back to origional, but I do like to try to maintain whatever origional aspects of the car remains. And it's sad that someone manages to gain a position on the food chain, and use incorrect configurations as the benchmark.)

As I said, the main lead, where the red cap is, was clocked @ 12. That means RIGHT UNDER THE HOSE. Correct clocking would slove the problem

Another configuration issue is the differences in alternator belts; how it relates to this case is anyone's guess. There is a difference in belts beteen w and w/o p/s. Even though I know the component match is correct--or is at least supposed to be if the factory did its thing correctly--the correct belt doesn't fit--too long and bottoming out on the adjustment braket. I played alon for 30 years with the belt issue. I think I also tried the w/o p/s and it was too short. After a few hit or misses, I had a guy fish up a belt that fits.

Okay, I clocked the terminal around to 12:00, it took the lower boss out of the way of the valve cover. The side terminals are on the top and the radiator hose is behind the housing by an inch or so. Only thing I'm not thrilled about is the way the wires are bent to clear the hose but if that's the way it was built so be it. It's not the worst thing i've seen go into the design of a car. If you spent some time with me at the GM or Chrysler tech center and saw how a car gets from concept to reality, you'd wonder how they get down the road. Bunch of idiots.
DJ

Finally found my pic.