Schwitzer Fan Clutch

[Ed S.]

Re: Schwitzer Fan Clutch

Ed,
Here you go...CJ stamped K&B Schwitzer repro.
https://www.paragoncorvette.com/p-36...utch-unit.aspx

Leif, that will work - Thanks

[Harry S.]

Re: Schwitzer Fan Clutch

The doc. that I have from Fred Oliva is:

Part number = 3814560, interchangeable with coil type.
Shaft painted silver, CJ is the Broadcast Code, Date Example is SC 7-18-66 where SC = Schwitzer, Drawings indicate the CJ Broadcast Code started 6-15-66, Big Block shaft = 1.5", Small Block Shaft = 1.8"

This is from his presentation that he gave at the 2007 National in Marlborough, MA

I forgot I had the presentation.

[Ed S.]

Re: Schwitzer Fan Clutch

Harry,
Thanks. Interesting issue here, not questioning you but.... according to the 64 Judging Guide, a 64 Corvette should have a clutch stamped with CJ, which is two years earlier than 6-15-66. Also, the shaft length for a SB should be 1.75, for me 1.8 is good enough for govt work. Wondering though if the JG is incorrect on the date info or the info from the presentation you quoted is off.

[Michael J.]

Re: Schwitzer Fan Clutch

The doc. that I have from Fred Oliva is:

Part number = 3814560, interchangeable with coil type.
Shaft painted silver, CJ is the Broadcast Code, Date Example is SC 7-18-66 where SC = Schwitzer, Drawings indicate the CJ Broadcast Code started 6-15-66, Big Block shaft = 1.5", Small Block Shaft = 1.8"

This is from his presentation that he gave at the 2007 National in Marlborough, MA

I forgot I had the presentation.

Freddie knows his stuff, I have one of his old cars.

[Alan D.]

Re: Schwitzer Fan Clutch

Often wondered about the CJ and CK, it has been said that the CK is for the BB, yes! So if only a small block existed until later in MY 65 why would one need either a CJ or CK? Never had either on my fan however never even looked until 2000 so with 70K + miles on car it probably worn off. As for judging - its on there now (can always remove).

[John S.]

Re: Schwitzer Fan Clutch

Jim
I have had it off and there is no date anywhere.

[Tony S.]

Re: Schwitzer Fan Clutch

Harry--dating for the Schwitzer started during the '65 model. Some '65 Schwitzer fan clutches are dated, some are not.

[David L.]

Re: Schwitzer Fan Clutch

Harry,
Thanks. Interesting issue here, not questioning you but.... according to the 64 Judging Guide, a 64 Corvette should have a clutch stamped with CJ, which is two years earlier than 6-15-66. Also, the shaft length for a SB should be 1.75, for me 1.8 is good enough for govt work. Wondering though if the JG is incorrect on the date info or the info from the presentation you quoted is off.

Ed,
I believe that the fan clutches with the "CJ" ink stamping did not appear until the 1967 model year as the "CJ" stamping is for GM # 3916139. GM # 3916139 did not exist before the 1967 model year. I once owned a "CJ" fan clutch dated "L27G" (Nov. 27, 1966) as shown in the link below.
Here is my research:
"CT" = GM # 3857531, 66-67 Corvette (427)
"CK" = GM # 3916141 , 68-69 Corvette (427)
"CJ" = GM # 3916139, 67 Corvette (327) & 67 Chevrolet w/AC
"CS" = GM # 3938944 (service fan clutch)

Dave

https://www.forums.ncrs.org/showthre...ghlight=clutch

[James W.]

Re: Schwitzer Fan Clutch

I have included a few pictures of my Fred Olivia restored original Eaton fan clutch from my '64 convertible and a 1967 dated Schwitzer fan clutch that was on my a/c equipped '65 coupe. The fan clutch on the '65 was replaced sometime prior to my dad buying the car in the early 1970's. I replaced it with a GM service replacement Eaton style unit back in 2008 since it was leaking fluid and not keeping the car cool. I am looking to replace the dated 1967 Schwitzer unit with a unit without a dated closer to the time when my '65 was built.


Regards,

James

[Chester K.]

Re: Schwitzer Fan Clutch

I cannot make out the date format on the Schwitzer fan clutch mounting flange. Is it in the SC 9.23.65 format, or is the SC after the date? Appreciate your input.

[David L.]

Re: Schwitzer Fan Clutch

The original Schwitzer fan clutch on my 1966 Corvette (body build date "F24" of Feb. 24, 1966) was stamped "SC 1-26-66" (Jan. 26, 1966).

Dave

[John L.]

Re: Schwitzer Fan Clutch

Gents
posted this picture before.....I always thought it was a very strange date code.....here's what I know ,.... owned the car since 1970... all numbers matching/dates matching base motor,.. built Mar 26th 1965... .restored/photo documented in 2007/20010,.....still on the car today after I added some fluid. So check the flange and no,...Its not my writing.
oops wrong build date month,..... car build Apr 26th 1965 there goes my credibility

[Jaime G.]

Re: Schwitzer Fan Clutch

Think 63/64 were undated, maybe dated by 65? My 64 is undated.

They began dating in 66

[Richard M.]

Re: Schwitzer Fan Clutch

This original clearly shows the date format.

More info HERE.

[Michael A.]