1969 Camaro Big Block fan clutch tutorial
 

Over the years many people have needed info on the '69 Camaro Big Block fan clutches only to find very little. I have put together some info and took pictures to help anyone out that needs documentation.

From what I have seen there are three styles of '69 fan clutches.

The most common style is the Eaton. They have the coiled thermal spring on the front.

The Schwitzer clutches have the flat bar going across the front.

The original GM part numbers are 3946049, and 3946050. In the parts book they can be found in Group 1.050.

Fan clutch 3946050 was used on the Special High Performance engines and was coded CZ

Part number 3946049 was superceded to part number 3946050 on 4/73. Part number 3946050 was discontinued from GM on 7/81.

It appears that the '69 and '70 Eaton fan clutches did not have "STORE THIS FACE DOWN" stamped into the face, and were left blank.

https://www.yenko.net/attachments/use...4-4510-008.jpg

These pictures are of the Schwitzer clutch. They measure 6" across and are 2 9/16" tall.

https://www.yenko.net/attachments/use...4-4511-006.jpg

The clutch is coded CI

https://www.yenko.net/attachments/use...4-4528-074.jpg

Backside

https://www.yenko.net/attachments/use...4-4512-014.jpg

The Schwitzer clutches are dated on the hub. This one is dated 6-10-69. Also note there is hardly any clearance between the hub and the clutch.

https://www.yenko.net/attachments/use...4-4513-018.jpg

There is 1 1/4" from where the fan sits on the clutch to where the hub sits on the waterpump.

https://www.yenko.net/attachments/use...4-4514-020.jpg

This picture is a Schwitzer clutch that is 7 1/4" across and is 2 11/16" tall. Hub is dated 3-13-69

https://www.yenko.net/attachments/use...4-4515-070.jpg

Backside

https://www.yenko.net/attachments/use...4-4517-021.jpg

CZ stamp

https://www.yenko.net/attachments/use...4-4520-025.jpg

Eaton CZ

https://www.yenko.net/attachments/use...4-4529-030.jpg

Backside

https://www.yenko.net/attachments/use...4-4521-039.jpg

Early Eaton CZ, and later with STORE THIS FACE DOWN stamping

https://www.yenko.net/attachments/use...4-4522-043.jpg

Another picture of an early Eaton clutch

https://www.yenko.net/attachments/use...4-4523-044.jpg

The Eaton clutch is 7 1/4" across, and is 2 5/8" tall. It also has the 1 1/4 space between where the fan rests on the clutch to the hub face that rests against the waterpump.


If anyone needs different picture angles, or more info just let me know. Also, none of the fan clutches are for sale.

Anyone out there know how to breakdown the ink stamped date codes?

- Warren

Re: 1969 Camaro Big Block fan clutch tutorial
 

A 17 J = Jan. 17th 1969

Re: 1969 Camaro Big Block fan clutch tutorial
 

Warren, is the measurement the same from the clutch to the hub on the Eaton and the Schwitzer CZ clutches?

Re: 1969 Camaro Big Block fan clutch tutorial
 

Nice info Warren. My info on early date code stampings coincides with Donnie. First character is the month followed by day and year.
Chris

Re: 1969 Camaro Big Block fan clutch tutorial
 

Thank you Warren, Mike, Bruce and all that have helped myself and those of us looking for the correct dated L78 Camaro components and a HUGE Thank you for Charlie and this site for getting us all together!!!

Now I just need to find one or two....

Fred

Re: 1969 Camaro Big Block fan clutch tutorial
 

All three style Big Block fan clutches have 1 1/4" spacing from where the fan rests on the clutch to where the hub meets the waterpump. The CV clutch has 1 1/2" spacing.

Thanks for breaking down the date code Donnie and backing it up Chris! I had a feeling that might be what it was. I have a CV clutch that is dated E 14 J and it is from an 05E Norwood Z/28.

- Warren

Re: 1969 Camaro Big Block fan clutch tutorial
 

Here are some pictures of the CV coded clutch.

https://www.yenko.net/attachments/use...4-4530-052.jpg

CV clutch with E 14 J date

https://www.yenko.net/attachments/use...4-4531-054.jpg

Ruler showing 1 1/2" from where fan rests on clutch to where the hub meets waterpump.

https://www.yenko.net/attachments/use...4-4532-059.jpg

The CV clutch is 3" tall, and is 7 1/4" across

https://www.yenko.net/attachments/use...4-4533-062.jpg

This CV clutch is dated D 22 A and is attached to a 70 1/2 LT1. Engine stamp is V0509CTB

Re: 1969 Camaro Big Block fan clutch tutorial
 

Good info guys - thanks for posting!

Re: 1969 Camaro Big Block fan clutch tutorial
 

Warren, Great job on posting this info & pictures. I have a Nov 68 built 69-396-325 with AC. It has a Eaton clutch on it with an "AC" marking and a date code of "B18D". Highlighted in photo. I can't seem to find any info on it and if it could be original. It needs to be rebuilt but I don't want to disturb the original markings if it is correct. Have you or anyone ever seen an AC stamp on the clutch? George.

Re: 1969 Camaro Big Block fan clutch tutorial
 

Nice job & great service to the community Warren. This picture is of one of the boxes that my Schwitzer clutchs came in. You have boxes pictured with the same part number along side both Schwitzer and Eaton clutches. It appears that the short shaft clutch from either manufacturer could have been stocked under the same part number - do your records agree?

https://www.yenko.net/ubbthreads/pics...4-img_2843.jpg