[wmurrell]

Does anyone know the correct ink stamping for the fan clutch on a '65 tripower with AC car? Thanks!

[Keith Seymore]

I can't comment on an AC car, but as a reference here are some markings from a Tripower nonAC car:









K

[wmurrell]

Does anyone know why some fan clutches have fins on the front and some do not?

[dld]

one is for standard and one is h/d use as 19.5 fan

[wmurrell]

dld,
Is the "PE" for the standard fan clutch and the "PF" for the HD fan clutch (with fins on the front)? Also, do you know the year of your HD fan clutch in the photo. It looks like a '68 or later design. Thanks!

[dld]

AFAIK the no fin in front clutch is std. the one with is the h/d . Keith s fan is correct it seems . But from what I have seen the pe and pf are correct codes for 65 ??. maybe more. The guy that did resto work on my fan has Eaton book with correct codes. He is in Florida don't remember name now. I will post pic of mine later. have to go to trailer to get it out.
Your correct on date code these are only file photos I have collected for reference to details.

Not correct for us but just to note similar look. see clutch on my buddys camaro

Don

[dld]

this looks correct. no fins that wrap around for standard fan blade

http://www.ebay.com/itm/1965-Pontiac...#ht_500wt_1077

[bill ryder]

Keith, I know this is an old thread, BUT I am still struggling with this fan clutch thing. Is the fan you showed in this post, with the blue paint dab, from your '65? I am using the same clutch, BUT seems like all I see on TP cars with 4 core radiators and fan shroud is the non fin faced clutch. This is one question I am trying to answer this winter. Just checking with you. May even send you a PM. THANKS bill

[Keith Seymore]

Originally Posted by bill ryder

Keith, I know this is an old thread, BUT I am still struggling with this fan clutch thing. Is the fan you showed in this post, with the blue paint dab, from your '65? I am using the same clutch, BUT seems like all I see on TP cars with 4 core radiators and fan shroud is the non fin faced clutch. This is one question I am trying to answer this winter. Just checking with you. May even send you a PM. THANKS bill

Bill - the fan clutch shown is from my '65 GTO.

There would be different fan clutches used (different part number and broadcast codes) for the different cooling packages. The various clutches are "tuned" (through different springs and internal fluids) to come on and kick off at pre-determined temperatures.

PM sent -

K

[bigpop]

Billy, I don't remember if I mentioned to you on the phone, but, I was under the impression, the rear end had a say in the cooling system ,ergo, the use of various
clutches and fans. I am certainly no engineer, but, a 3:90 and 4:33 would ,through
even normal driving, would tend to cause an increase in heating in the engine.I believe, that is why the finned clutch is used. The physics of it are not in my domain, but, seems to me that the clutch,with increased surface area,and the design of the fins, causes it to make fan rotate faster( 19-1/2"), dissipating more heat in the engine,derived from the rear ratio. But, I ain't no engineer! LIL Bro

[bill ryder]

The clutch in post #4 is July 17, 1967 I believe and Keiths clutch is Sept. 12, 1964. Hope I got this correct!! bill

[dld]

this one is Nov.29th 64 and is for standard bent tip fan.

[bill ryder]

THANKS DON. Now all I have to do is remember it!!!

[bigpop]

Don's got it correct, but, I have a question about his finned clutch ( photo#4) I see his
fins are straight up and down, every other one HD I have seen, has the fins angled, like Keith's. Any one know why the diffence? I can only guess a different division(Chevrolet?) I have seen NOS Chevy clutches, and they at least in this era, all had other info engraved on the face.e.g. Eaton and so forth. Pontiac's do not seem to have this feature. Any ideas?
One more thought, I have had a few NOS standard ( flat-face) 64-65 Clutches, and each had a daub of Pontiac Blue Engine paint(64-65), and, a yellowish/tan daub. Both on the edge of the front, next to one another. Ideas? On the second daub I mention?
Larry B.

[goatman65]

So is the 'gold' plating on Keith's fan worn off? or did some not have it?

I have an aftermarket fan on my 65 but want to go to a clutch fan. I have a 7 blade,bent-tip fan,about 17 1/2 inch. The clutch appears to have DE stamped and something else that is worn too bad to make out.

I have no idea what it is off of, it was on a 67 a/c GTO with a 65 389 engine.
Anyway to tell if it is from a Pontiac?

[dld]

the gold is a flash coat over the base plating. it fades off quick. will leave a rainbow look as fading.

[64woodwheel]

Here is a NOS 545491. '64 23 26 28 w/ AC exc. 421 4BC & 3/2BC.
It looks like the 64 GTO clutch (non HD), but that part number is 9775578.
Does anyone know what the difference is? Reason I ask is this clutch is for AC and does not have the fins on the front. The date code on this is B12F. Feb. 12, 1966? ?

[bill ryder]

I'm probably wrong but I thought the letter F would be '65, A is '60. Wrong, right??? Keiths fan was E, late '64 for his early '65. Someone straighten me out!!!!!!!!!! bill

[goatman65]

I think this may be a Chevy fan. It is painted black between the fins both front and rear.
It has front fins like a H/D unit.
At the top is the ink stamp,looks like 3 or 4 letters/numbers. The only one i can make out is the first number either a 6 or 9.

It was bolted to what looks to be the original 17 1/2 inch fan. The fan is 7 blade bent tip,natural finish.