*** '68 fan question ***
Thread Starter
Safety Car
Joined: Jul 2009
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From: Saskatchewan, Canada
*** '68 fan question ***
How do I determine the correct fan assembly for my '68 L36 427 with no A/C??? Any special markings on the fan??? What is the correct diameter??? (what is the proper way of measuring this?). Thanks in advance.
Team Owner
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From: Southbound
Cruise-In II Veteran
Use the original part number in the AIM. I'm not certain of the diameter, but it's likely to be 17 1/2". The blade assembly might have a GM part number stamped on it.
Last edited by Easy Mike; May 9, 2011 at 10:23 AM.
Racer
Joined: Dec 2010
Posts: 345
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From: Baldwinsville New York
Easy mike is correct but there are a couple of things to look for but first what is the production date of your car? During late 68 gm made changes to the fan due to overheating problems. Plus if your 68 is a early or early late production the fans for a/c and non a/c car differ. I did a lot of homework on this subject when I wax restoring my 68 to NCRS standards. Jeff
Thread Starter
Safety Car
Joined: Jul 2009
Posts: 3,719
Likes: 95
From: Saskatchewan, Canada
Easy mike is correct but there are a couple of things to look for but first what is the production date of your car? During late 68 gm made changes to the fan due to overheating problems. Plus if your 68 is a early or early late production the fans for a/c and non a/c car differ. I did a lot of homework on this subject when I wax restoring my 68 to NCRS standards. Jeff
Much appreciated. BK3
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a/c cars had had 7 blade fans & non a/c cars had 5 blade fans
I run my non a/c car with the factory 7 blade fan for extra cooling. should be poorly painted gloss black ( spotty ) most 5 blade fans did not have a date code. The date code on the a/c 7 blade fans was a letter for the month A = Jan B= Feb etc..........followed by 2 digits for the year.
I'll get back to you shortly with the part number when i'm home.
I'll get you the 5 & 7 blade part numbers.
ZIXXXPACKER
I run my non a/c car with the factory 7 blade fan for extra cooling. should be poorly painted gloss black ( spotty ) most 5 blade fans did not have a date code. The date code on the a/c 7 blade fans was a letter for the month A = Jan B= Feb etc..........followed by 2 digits for the year.
I'll get back to you shortly with the part number when i'm home.
I'll get you the 5 & 7 blade part numbers.
ZIXXXPACKER
Racer
Joined: Dec 2010
Posts: 345
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From: Baldwinsville New York
Hi bk3. I did not forget you but I will get you theinfo tomorrow. I was traveling for work all day for work. Jeff
Thread Starter
Safety Car
Joined: Jul 2009
Posts: 3,719
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From: Saskatchewan, Canada
I just came in from playing baseball (batting practice) with my wife and 2 sons - ages 8 & 5 -very fun quality time with the family. BK3
Last edited by bkvette3; May 11, 2011 at 10:33 PM.
Racer
Joined: Dec 2010
Posts: 345
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From: Baldwinsville New York
Here is some info for you
1. If your Trim Plate is D24. Then is means D=November of 67 the 24 means the 24th day of November. Therefore your Body Build Date is November 24, 1967. Being that then, your car is an early 68 car.
2. If your engine stamp has you stated TO921IQ then this decodes to
T= Tonawanda. 0921 = September 21. IQ = 427/390 Hydra-Matic with a Q Jet Carb.
3. The Fan should be gloss black paint. I have seen and original fan and the paint was very poorly done. When I did mine, I made look better then original. Your car being a Non-AC car should have a 5 blade fan. Do to overheating issues the 68 in very late production cars would have started to see seven blade fans on Non A/C Cars. A/C cars where a little different during 68. A/C cars usually have a seven blade fan, which the part number and date code would have been stamped on one or more of the blades. The fan date codes were in a alpha character of the month (a=Januaray B= Feb)... and the two numbers of year of production. My car is an original A/C car and I have a 5 blade fan. The difference is my 5 blade fan on a A/C cars had a greater pitch to the blades from what your would be or Non A/C. It was not to very late 68 they put 7 blades fan on A/C cars. My car is a May production.
I would this helps.
Jeff
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Racer
Joined: Dec 2010
Posts: 345
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From: Baldwinsville New York
Anytime. Hopefully this info was helpfully. 68 as you know had so many running
Changes. I did a total frame off restoration on my 63 coupe and being
A first year body change was nothing compared to doing my 68. Glad I did it but
would not do it again. At least not to extent I did. Have a good weekend
Jeff
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From: spring branch Texas
This is a five blade fan, 17 1/2"---measure by laying fan on a clean sheet of paper, draw two lines from opposing mounting holes to get the "center", then measure from the intersection of the two lines to the end of each fan blade---you should get apx. 8 3/4" on each.
The center diameter is 2 3/8"
The bolt holes are 3" (measuring across--center to center)
The pitch is 2 1/4"---measure by laying fan on flat surface then measure from surface to highest point on each fan blade
The fan's center hub should have 3 stampings:
1) 66 (can appear as 99)
2) FRONT
3) H
5 rivets per blade, "flat" round head
Also, each fan blade should measure 5.93", and the measurement from the bottom of each fan blade to the first rivet should be 1.44"
That about covers it.
These are rather expensive----$450.00 to $600.00
Racer
Joined: Dec 2010
Posts: 345
Likes: 1
From: Baldwinsville New York
:
The correct fan for your '68 427 (a/c or non) is part number 3888366
This is a five blade fan, 17 1/2"---measure by laying fan on a clean sheet of paper, draw two lines from opposing mounting holes to get the "center", then measure from the intersection of the two lines to the end of each fan blade---you should get apx. 8 3/4" on each.
The center diameter is 2 3/8"
The bolt holes are 3" (measuring across--center to center)
The pitch is 2 1/4"---measure by laying fan on flat surface then measure from surface to highest point on each fan blade
The fan's center hub should have 3 stampings:
1) 66 (can appear as 99)
2) FRONT
3) H
5 rivets per blade, "flat" round head
Also, each fan blade should measure 5.93", and the measurement from the bottom of each fan blade to the first rivet should be 1.44"
That about covers it.
These are rather expensive----$450.00 to $600.00
This is a five blade fan, 17 1/2"---measure by laying fan on a clean sheet of paper, draw two lines from opposing mounting holes to get the "center", then measure from the intersection of the two lines to the end of each fan blade---you should get apx. 8 3/4" on each.
The center diameter is 2 3/8"
The bolt holes are 3" (measuring across--center to center)
The pitch is 2 1/4"---measure by laying fan on flat surface then measure from surface to highest point on each fan blade
The fan's center hub should have 3 stampings:
1) 66 (can appear as 99)
2) FRONT
3) H
5 rivets per blade, "flat" round head
Also, each fan blade should measure 5.93", and the measurement from the bottom of each fan blade to the first rivet should be 1.44"
That about covers it.
These are rather expensive----$450.00 to $600.00
