Identify Correct 72 Alternator Fan??

[Norm C.]

I have received a correct dated alternator, but not sure if its the correct fan. Could not locate in archives an "Alternator Fan ID" discussion,,,,, could any of the judges help describe the fan blades and if there are any stamps or other features of the correct fan?
As always.... thanks in advance for any assistance!!!

[Joe L.]

Re: Identify Correct 72 Alternator Fan??

I have received a correct dated alternator, but not sure if its the correct fan. Could not locate in archives an "Alternator Fan ID" discussion,,,,, could any of the judges help describe the fan blades and if there are any stamps or other features of the correct fan?
As always.... thanks in advance for any assistance!!!

Norm-------


While there are slight differences in the 2 fans shown in the attached photo, I believe that both are GM #1966990 and I believe this is the fan used for 1972.


DSCN0676.jpg

[Norm C.]

Re: Identify Correct 72 Alternator Fan??

Thanks Joe!!!! Just couldn't ask for anything better than that!!

[David L.]

Re: Identify Correct 72 Alternator Fan??

Joe,

I believe that that the fans in your photo are not the same number. Apparently in my photo below the LABELS ON MY TWO FANS SHOULD BE SWITCHED. I believe that one of the fans in my photo below is GM # 1969448 as referenced in the Sept. 13, 1968, Technical Service Bulletin. I guess the fan on the right side in my photo with the "shark fin" is actually GM 1966990 as it is the same as your NOS 1966990.

Dave

[Joe L.]

Re: Identify Correct 72 Alternator Fan??

Dave-----


The GM #1966990 is from the box beneath it. So, I'm sure it is a 1966990. The other fan in my photo is the original fan from my 1969 GM #1100859 alternator. That alternator was manufactured in August, 1969. The GM #1969448 was discontinued from SERVICE in May, 1969 and I expect it was dropped from PRODUCTION use well prior to that time. It was replaced by the 1966990 and I expect that's what was used on my alternator and pictured.

The "notch" in the blade, which you also point out in your photo, is the only real difference between the two fan blades I pictured. My original fan has only a very slight "notch" and the NOS 1966990 has a more pronounced notch. However, this could have been a change to the drawing for 1966990.

[David L.]

Re: Identify Correct 72 Alternator Fan??

Joe,

I sure would like to see a NOS 1969448 fan.

Dave

[Joe L.]

Re: Identify Correct 72 Alternator Fan??

Joe,

I sure would like to see a NOS 1969448 fan.

Dave

Dave------


Unfortunately, I do not have an NOS example of the 1969448. Its having been discontinued so long ago, finding one would be difficult. Since GM rarely included a stamped part number on alternator fans, positively identifying a used piece is impossible.

I expect the use of the 1969448 in PRODUCTION probably ended about the date of the service bulletin you posted a copy of.

[David L.]

Re: Identify Correct 72 Alternator Fan??

Joe,

The 1969 Camaro Parts Catalogue (Nov. 1968) lists the following:

2.274 Fan, Delcotron

1966990 1968-69 ALL 37 or 42 AMP
1969448 1968-69 ALL 63 AMP

Do you have any idea why?

Dave

[David L.]

Re: Identify Correct 72 Alternator Fan??

Joe,

Have you ever seen an alternator fan like the one in the photo below?

Dave

[Joe L.]

Re: Identify Correct 72 Alternator Fan??

Joe,

The 1969 Camaro Parts Catalogue (Nov. 1968) lists the following:

2.274 Fan, Delcotron

1966990 1968-69 ALL 37 or 42 AMP
1969448 1968-69 ALL 63 AMP

Do you have any idea why?

Dave

Dave-------

I think this is one of those "questionable" references in the P&A catalogs. I think the 63 amp alternator of the late 60's was used in few, if any, passenger cars. I believe it was a different series alternator than was generally used in passenger cars (i.e. it was not a "DN" or "SI" series). In any event, I'm virtually certain that the 63 amp unit was never used in Corvettes.

[Joe L.]

Re: Identify Correct 72 Alternator Fan??

Joe,

Have you ever seen an alternator fan like the one in the photo below?

Dave

Dave------


I don't think the black paint is original but I believe the fan is a GM #800594. This fan ultimately replaced most of the other alternator fans.

[David L.]

Re: Identify Correct 72 Alternator Fan??

Dave------


I don't think the black paint is original but I believe the fan is a GM #800594. This fan ultimately replaced most of the other alternator fans.

Joe,

Enclosed is a photo of a NOS 800594 fan that I bought at my local Chevrolet dealer.

Dave

[David L.]

Re: Identify Correct 72 Alternator Fan??

Dave-------

I think this is one of those "questionable" references in the P&A catalogs. I think the 63 amp alternator of the late 60's was used in few, if any, passenger cars. I believe it was a different series alternator than was generally used in passenger cars (i.e. it was not a "DN" or "SI" series). In any event, I'm virtually certain that the 63 amp unit was never used in Corvettes.

Joe,

I assume 1968 Chevrolets w/AC (maybe only in Canada) used a 63 AMP alternator as referenced in the Sept. 1968 Technical Service Bulletin concerning the noise problem with 1968 passenger cars equipped with V8 and Delcotron high speed fan (GM # 1969448). According to my research the 1968 Corvettes with AC used a 61 AMP alternator, 1100750. According to the 1968 Camaro AIM V8 models w/AC used a 1100796 alternator, 61 AMP.

Dave

Dave