Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

[Wayne M.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

My original has "3858533 BJ" and "GM" stamped on it, and I can't see any other markings. ...A close look at pictures of the current 3858533 pulley on two of the vendor sites (which may be the current GM production piece) showed a distinct lip around the outer perimeter that is definitely not present on the older NOS and original 3858533 pulleys, and I could not see any "BJ" stamped after the part number.

The fairly recent NOS (circa 2005) GM 3858533 pulleys appear to be made in Canada, and are very similar to my original, with "BJ" and "GM" stamped in the center area of the pulley. The only difference I could see is that there is an additional set of numbers/letters stamped, e.g., "C5" over "S2".
.....

Scott -- as to stampings, here's the 904/533 set on my '65 air L76; which I've owned since 1980 and I believe the pulleys to be original. Of interest is the script (sans serif ? serif ?) and no suffix letters after the 533 part #, or the 904. Notice the 'S' below the 'GM' near the bolt hole on the '533, and below the 'GM' on the 904.

[John D.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

Here's the part drawing for the pulley...it's consistent with the pics posted so far...........

[Scott S.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

Scott -- as to stampings, here's the 904/533 set on my '65 air L76; which I've owned since 1980 and I believe the pulleys to be original. Of interest is the script (sans serif ? serif ?) and no suffix letters after the 533 part #, or the 904. Notice the 'S' below the 'GM' near the bolt hole on the '533, and below the 'GM' on the 904.

Thanks for the pictures, Wayne.

My water pump pulley is like yours, same lettering in an arc, but followed by the letters CS, so the whole part number reads: 3848904 CS. On the opposite side of the water pump pulley, mine has the same "GM" over the letter "S", in the same font/script.

A closer look at my cracked original crankshaft pulley (3858533 BJ) showed the "GM" over the letter "S" too, it's just harder to see. In the next post I'll attach close up pictures of the old vs. what was described as a 1970s vintage NOS crankshaft pulley (flat black phosphate?), there is a point mentioned in John's drawing about the letters following the part number that I will address in the next post.

Picture 1) water pump pulley 3848904 CS
Picture 2) water pump pulley, opposite side, showing "GM" over "S"

Picture 3) old crankshaft pulley (3858533 BJ and "GM" over "S")
Picture 4) new "old" NOS crankshaft pulley (3858533 and "GM" over "S")

[Scott S.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

Here's the part drawing for the pulley...it's consistent with the pics posted so far...........

The print in the drawing is small, but it appears to say:

"Stamp part No. 3/16 - 1/4
high followed by BJ
Must appear in this area
This side, radial location
unimportant."


If anyone has more information on this, I would like to learn.

Picture 1) cracked original crankshaft pulley, "GM" over "S"
Picture 2) cracked original crankshaft pulley, "3858533 BJ"

Picture 3) old (1970s?) NOS crankshaft pulley, "3858533" (missing "BJ")
Picture 4) old (1970s?) NOS crankshaft pulley, "GM" over "S"

[John D.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

The part drawing for 3848904 shows the finish as phosphate followed by "Parcolac 30"...does anyone know what that is ?....google shows some sort of rust inhibitor named Parcolac but it may just be semi gloss black paint......

[Joe L.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

The part drawing for 3848904 shows the finish as phosphate followed by "Parcolac 30"...does anyone know what that is ?....google shows some sort of rust inhibitor named Parcolac but it may just be semi gloss black paint......

John------


I think the "Parcolac" is, basically, a rust inhibitor. I think it's what gives these old phosphate-finished pullies that sort of "oiled" appearance with a very slight brownish tint. You only really see this, though, in really old, NOS pullies. In use, I think the Parcolac rather quickly "goes away".

Most of the original pullies for balancer and waterpump were phosphate-finished. At some point, maybe in the 70's, or so, the finish changed to semi-gloss black paint. The 3858533 available in SERVICE for the past 25 years, at least, has been semi-gloss black painted.

Also, most of the original pullies used in the 60's had the old style "GM" logo embossed on them as is seen in the photos. This same style logo is seen on the old yellow-and-black SERVICE parts boxes.

[John D.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

Thanks Joe that makes sense to me....

[Scott S.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

Joe, do you have any information about the "BJ" suffix after 3858533?

The "old" NOS pulley I recently acquired looks nearly identical to my original, it's not semi-gloss black but appears to be black phosphate (if I understand that correctly), except for missing the two letters after the part number that are described in the drawing that John attached (post 17).

I have seen more recent NOS examples (claimed to be from around 2005) with the GM box showing "Made in Canada" on the box, and they do have the letters "BJ" after the part number on the pulley, along with the "GM" stamp, but then they also add a few other letters (I have seen "C5" over "S2").

[Joe L.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

Joe, do you have any information about the "BJ" suffix after 3858533?

The "old" NOS pulley I recently acquired looks nearly identical to my original, it's not semi-gloss black but appears to be black phosphate (if I understand that correctly), except for missing the two letters after the part number that are described in the drawing that John attached (post 17).

I have seen more recent NOS examples (claimed to be from around 2005) with the GM box showing "Made in Canada" on the box, and they do have the letters "BJ" after the part number on the pulley, along with the "GM" stamp, but then they also add a few other letters (I have seen "C5" over "S2").

Scott------

"BJ" is the broadcast code for the GM #3858533 pulley. In fact, it is shown on the drawing that John posted. Primarily, this code was for use on the assembly line to make it easy for line workers to quickly identify the correct pulley to be installed on a particular car. The same sort of broadcast code system was used for MANY other components, usually when there was more than one part used depending on the particular vehicle.

In later SERVICE the "BJ" may have disappeared. I have quite a few of these pullies but I can't go out and check on it right now. Keep in mind that after this pulley ceased being used in PRODUCTION, the broadcast code probably became superfluous as far as GM is concerned and this pulley has not been used in PRODUCTION for 30 years now.

Many GM SERVICE pullies for older applications are manufactured in Canada. In fact, many pullies used in current PRODUCTION are made in Canada, too.

[Scott S.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

In later SERVICE the "BJ" may have disappeared. I have quite a few of these pullies but I can't go out and check on it right now. Keep in mind that after this pulley ceased being used in PRODUCTION, the broadcast code probably became superfluous as far as GM is concerned and this pulley has not been used in PRODUCTION for 30 years now.

Many GM SERVICE pullies for older applications are manufactured in Canada. In fact, many pullies used in current PRODUCTION are made in Canada, too.

That's the mystery. Wayne's is at least 30 years old (he bought his car in 1980) and there's no "BJ" after the part number. The NOS example I just received was represented as an "old" NOS from the 1970s, and appears to have the dull/flat black phospate finish typical of original and early service parts (if I understand that correctly), but it's missing the letters "BJ".

The modern-era NOS (circa 2005) examples made in Canada have added the "BJ" back again, after the part number, decades after it had been removed from production, but they also added a few more numbers and letters that are not present on originals or older NOS examples.

In any event, I'm trying to decide whether to keep this example, or keep looking for one with the correct letters after the part number. I didn't see anything in the JG that mentions this in detail, but I don't know if that's significant or not.

[Joe L.]

Re: Cracked crankshaft pulley 3858533 BJ - weld / repair or replace?

That's the mystery. Wayne's is at least 30 years old (he bought his car in 1980) and there's no "BJ" after the part number. The NOS example I just received was represented as an "old" NOS from the 1970s, and appears to have the dull/flat black phospate finish typical of original and early service parts (if I understand that correctly), but it's missing the letters "BJ".

The modern-era NOS (circa 2005) examples made in Canada have added the "BJ" back again, after the part number, decades after it had been removed from production, but they also added a few more numbers and letters that are not present on originals or older NOS examples.

In any event, I'm trying to decide whether to keep this example, or keep looking for one with the correct letters after the part number. I didn't see anything in the JG that mentions this in detail, but I don't know if that's significant or not.

Scott------

Then I'd say it's pretty much for sure that some original pullies didn't have the broadcast code stamped on them even though the GM specifications for the part required it. What does this mean? I don't think it means anything other than, for whatever reason, the code was omitted.