So...I have not gone up in my parts loft yet, but pulled some pics off my files for stellar et al interested in platings + info. I think the few pulley pics are a typical NOS 442 pulley, I'm too lazy to check the #. You can see they have just a tinge of gold. The Heartbeat pulley is repro, you can see it's heavy gold. The other pics are just misc NOS fan pics I've sold in the past. There's a nice pic of a galvanized fan. The fans had to be plated to prevent rust. There were many different styles of fans + pullys. Some years, like the open years...there were different pullys used on the same alt. Typically, around 69/70 the famous "shark tooth" fan came into use. I've got an NOS one, I've got a few used I think, but too lazy to look for them. It seems I read somewhere that the "shark tooth" fan made a lot of noise and was recalled + changed to a toothless fan. 'Course in the old days...recalls only meant if a customer complained then they would fix it. So...even though GM KNEW those toothed fans made noise, they only changed them if the customer complained. Eventually they changed the design. Small + large fins, teeth, number and spacing of fins I think changed as the alts got more powerful, they got hotter, too. Here's the pics.....

 

Lazy here too, and I am having a bald moment....
Whats the "sharks tooth..' look like?

Thanks, Brett

 

Nice info, but why the outrage over GM KNEW? Perhaps a bit of noise for better cooling is a better solution than a quieter fan with less airflow. Turbulence makes noise, but it means airflow. I would much rather have some noise and a longer lasting alternator than a grandma special that burns them up. Not only is it cost effective to only swap out parts that might annoy some people when they complain; it's smart, seeing as how the power users aren't going to be the ones bitching about the noise.

 

I suppose you are right in this case. But...you know...there were safety recall issues back then, too. Some were quietly fixed by the dealers when the cars were serviced. The public was not made aware of these issues, or notified to have their cars fixed. There were TSB's sent to the dealers. I agree...noise isn't a big issue, especially on 455 4BBL's! But safety is another thing. I know you work in the industry, but I feel better with the government overseeing some stuff. Anyways...here's a "toothed" fan pic for paladin. This one has been painted black. It seems like some had a pointier tooth than others. This is the fan that came on most early unmolested open face alts. https://i.ebayimg.com/thumbs/images/...GgH/s-l225.jpg

 

I totally agree on the safety thing. Negligence is nothing else but negligence. I appreciate your pics, love learning this stuff.

 

Here is more info from a Z site. I'm not sure why the "toothed" fan made noise, if it was more efficient or not, or why the "tooth" was put there originally by the engineers. I DO know they are somewhat coveted by the 'vette guys. http://nastyz28.com/threads/1970-z28...or-fan.221247/

 

Nice pics. Thanks. The vet fans pics 1 and 6 look like they are zinc plated with clear chromate. Very shiny. I always thought they were cadmium plated which is a bit dull in appearance. Do you think they were made later when GM started using zinc instead of cad? I like the shiny look better. Pic 2 is a Ford fan and looks galvanized. I think it should have a gold tint. The ford fan is a tiny bit larger diameter. On some applications it will rub the adjusting brace. The pulley pic 5 is also Ford. Pics 3 and 4 look to be replated zinc. Pics 7 and 8 look like new a zinc plated pulley. Thats my thoughts. I'm looking forward to any other thoughts. Thanks for the pics

 

You may be right stellar, those 'vette fans may have been a later plate, but the box style is old. I've noticed the Ford fans typically have like a circle at the bottom of the fin slots. Plating on the fans seems to vary, although I still don't think I've seen a gold factory GM fan of that era.
A couple things more to mention for you alt fan freaks (you know who you are!). First thing is what I would call the gold fan sydrome or effect. It seems about 15 or 20 years ago, most of the the rebuilders began putting gold plated fans and pulleys on their rebuilt alts. They do look kind of spiffy, so if you had a ratty or bad alt, you would chuck one of these gold jobs on and it looked "new". Then what happened was you would go to a car show and 17 or 18 GM musclecars had rebuilt alts with gold stuff on them. Then people think that's how they should be, or were originally.
The other thing about the fans and alts is the open face alts. Starting in 1969 or so GM began integrating the voltage regulator inside the alternator. I think for Olds it was only the 442 that had the voltage regulator inside the alt. The Cutlass still had the regulator separately mounted on the firewall. I think 'vettes, some Firebirds and the GTO got the open face alts first. I guess GM knew they would make more heat internally, because at the same time they were upping the amps. So...the open design was for heat release, I think. They also added the "diamond back" to dissipate heat. Finally, they changed the fan design at the same time to move more air. Anyways, the open back hung around GM for a few years. Then there were problems with the open face...it was weak...some developed cracks, broke, etc. So it was only a few years and the face was re-designed to be stronger. The fan design was changed again, too. That's why they bring the $, because only a few years they were made, and many cracked or broke and the faces were replaced. Weirdly, I have a couple factory pics of GS cars with the open face. But, to my knowledge Buick never used them!

 

The galvanized (left) fan is an aftermarket universal fan (Tiawan). The (right) fan is ford that has been blasted. 1100924 is an unmolested Buick openfaced. The 1100937 is an unmolested Cadillac openfaced. I have never seen another Buick or Cad openfaced original alt. I have been trying for a long time to determine the correct plate and color for the various fans in specific years, but no matter what combo I think is right (except for the very early years) someone always has a different opinion. I wonder if anyone knows with 100% certainty or if maybe it isn't even a cut and dry subject. Cad vs zinc, silver vs gold? I suggest go with what you like best.

 

Sharks tooth or hooked fan

 

thank you Mr for the pics , and I will now have to start digging thru the boxes to see if I have a correct one.
So the addictions continue...
Brett

 

Great Info. I had a complete NOS 890 alternator with original fan and pulley on my 70 W-30. The fan was a galvanize style coating and the fan had a gold tint to it. Also had the "shark tooth fan" I will look for pictures of it tonight and post them

 

Thanks stellar...wow...Buick + Cad opens, never seen them and I'm an old guy who spent a LOT of time in the boneyards. Are both those diamond backs? The one in the latter pics, that fan with the notch in the blade looks to be a later style fan than open faced used. Sometimes I think it's like carbs, when they rebuilt them, they just put them all on a table, and the workers mixed the parts up. You definitely see that on carbs, starters, and distributors. Another thing of interest to you guys may be the stamp. The first open stellar shows has an ink stamp near the number. Looks like maybe BB. All the GM alts had an ink stamp in addition to the hard stamped number. The ink stamp code is usually in the assembly manual. Olds open years were like AZ AN or AM...I forget off hand. Earlier GM alts had an ink stamp number. If the alt was say 1110654 (made up) then 654 was stamped on the alt in like 1/2" (?) letters. I think this was for the assembly line guys so they could pic up the right part fast.

 

Unfortunatly neither the Cad or Buick open faced had the diamond back. The Buick 1100924 is dated 0G1 (July 1st 1970) The ink stamp is BP with the number 1 under it. The Cad alt 1100937 is dated 0K6 (oct. 6th 1970) which would make it for a 1971 model. This is the one with the notch in the fan.

 

This is an original 890 for a 70 442 that had never been bolted on a car. Just thought I would post these pictures for reference.

 

Very nice. Even the regulator is date coded. I have only seen a few with the date coded reg. The fan does not look to be gold tint. Is it? The pulley looks like it may have gold tint in one pic, but it looks silver in another. I like the #5 on there.

 

That's a nice piece! The 5 on the pulley is the last digit of the part #1949355. See the old post below. No time to post more tonite, I'll get back with more info tomorrow.
https://classicoldsmobile.com/forums...or-pulley.html

 

Only the pulley had a gold tint but it was for sure not gold cad. I do not know what the coating was.

 

My guess would be the pulley was zinc coated with the yellow dichromate. I think only the diamond back alts had date coded regulators.

 

Thank you all for all this information and great pictures ! The aftermarket Alternator i have on the car is a close match to the one Jensenracing77 has pictured ! Guess I'll have to re cad the pulley since mine is showing some l plating ( Paint) loss ! And change the fan color from black ! Great info and reading !

 

I'm not sure if you guys are aware of this, but the shark fan has been repro-ed recently.

 

 

I'm not positive Al, but I think there is one more hook style with a sharper "tooth".

 

Thank you for pics and info, great information for inquiring minds!