Change To Hi-perf Alternator Pulley

[Tom R.]

I'm changing the alternator pulley to the Hi-Perf pulley on my 63 L84 with the thicker back from the smaller diameter existing pulley. I bought the Hi-perf pulley from Paragon, Part No 1648.

When I removed the smaller existing pulley, it had a concave back to accomodate the alternator fan which was convex toward the front of the car, and the fan used a spacer behind it to keep it from hitting the alternator case. Since the Paragon pulley doesn't have this concave area, and instead is machined flat with a little boss that sticks out about a 1/8", there are no threads to be seen in the front to attach the bolt when I slide it on next to the alt fan. Plus, it looks funny as the pulley is not flush with the alt. fan since it has that covex shape.,

Is there a different alternator fan with a shorter spacer that I need or what am I doing incorrectly? Any pointers would be appreciated.

[Wayne M.]

Re: Change To Hi-perf Alternator Pulley

Sounds to me like you' ve got the wrong fan. Should be concave towards the front. Fan on right in the pic came on a '65 with the big pulley [L79, L76) base or L84]; you can see the outline of the large diameter. Shown as installed in the 2nd pic.

[Tom R.]

Re: Change To Hi-perf Alternator Pulley

Sounds to me like you' ve got the wrong fan. Should be concave towards the front. Fan on right in the pic came on a '65 with the big pulley [L79, L76) base or L84]; you can see the outline of the large diameter. Shown as installed in the 2nd pic.

Thanks for the reply Wayne. That's what I thought. I don't think I've seen these for sale anywhere, would you or anyone have any leads on this? And does it require some sort of spacer or washer between the fan and the shoulder on the alt shaft and between the pulley and the fan? Seems like the fan blades will take the full bearing from the pulley and not along the shaft.

[Tom R.]

Re: Change To Hi-perf Alternator Pulley

Does this look like the correct fan?

https://www.forums.ncrs.org/attachment.php?attachmentid=28975&stc=1&d=1293656957

LICS says it's for a 63 with no other data.

[Timothy B.]

Re: Change To Hi-perf Alternator Pulley

Tom,

That's the fan for 63 alternators, I believe the spacer you are refering to is used on all alternators.

[Wayne M.]

Re: Change To Hi-perf Alternator Pulley

T ......And does it require some sort of spacer or washer between the fan and the shoulder on the alt shaft and between the pulley and the fan? Seems like the fan blades will take the full bearing from the pulley and not along the shaft.

Tom -- here's the order: thicker spacer is between armature core and inner face of bearing race; bearing; thinner spacer between outer face of bearing race and fan; pulley buts up against fan; then the wavy washer and big nut.

About that LIC fan; IMO NO; it has 13 equal blades. Believe all C2's had 11-blade fans with blade size varying (see my previous big pics). Has something to do with eliminating fan harmonics.

[Tom R.]

Re: Change To Hi-perf Alternator Pulley

Tom -- here's the order: thicker spacer is between armature core and inner face of bearing race; bearing; thinner spacer between outer face of bearing race and fan; pulley buts up against fan; then the wavy washer and big nut.

About that LIC fan; IMO NO; it has 13 equal blades. Believe all C2's had 11-blade fans with blade size varying (see my previous big pics). Has something to do with eliminating fan harmonics.

OK Wayne,

The fan I have now (convex forward) also has 11 blades and not spaced equally. Off to find the elusive 11-blade concave forward fan. Anyone?

[Tom R.]

Re: Change To Hi-perf Alternator Pulley

I think this is the one Wayne is showing although LIC says it's for a 64-7.

[Timothy B.]

Re: Change To Hi-perf Alternator Pulley

Tom,

I stand by my previous post stating the fan you pictured is the 63 fan with 13 blades. I believe the style with 11 uneven shaped blades started in 64 for the reasons Wayne stated about noise.

[Jim L.]

Re: Change To Hi-perf Alternator Pulley

Tom,

I stand by my previous post stating the fan you pictured is the 63 fan with 13 blades. I believe the style with 11 uneven shaped blades started in 64 for the reasons Wayne stated about noise.

This is correct. '63 fans have uniform sized blades; fans for later years have uneven sized blades.

Jm

[Tom R.]

Re: Change To Hi-perf Alternator Pulley

Timothy and Jim,

Thanks for the insight. My AIM doesn't make a distinction and no part no is shown for the fan. I'll get the correct one.

[Tom R.]

Re: Change To Hi-perf Alternator Pulley

Thanks to all for your help. Finally got it all bolted back together with the 13-fin alternator fan and the parts fit just like you all said they would. I do notice a little whirring noise that wasn't there before when revving, but that's a 63 for you! It looks a lot better now.