Fan blades

[Impalaguru]

I've got the car back on the road now and am begining to wonder about my fan blade. Everything is original GM parts except the fan clutch. The fan is almost all the way in the shroud (original 409 shroud with factory slant-top radiator with factory spacers). Maybe about 1/4-3/8" sticks out of the shroud. Could my new clutch be a little too long? I have the original and it looks about the same. Does anyone have this set up with the fan not all the way in the shroud? Do I even need the fan clutch? I had an aluminum fan on there before with no clutch and it did OK. Someone also suggested I use one of those 4-blade fans like off of a 283. They said they were a good fan and moved a lot of air
Ross

 

[Ronnie Russell]

Ross, I would say "yes" you need the fan clutch. As far as combinations go, there are many. I remember about a year ago, Bob Walker Jr. described the fan clutch and blade he is using. I remember that I was impressed with his set-up and when I get closer to installing engine , Im gonna pick his brain on the subject.

 

[Aqua 409]

Ross

That's great getting the car on the road! I have the fan clutch, blades, shroud and slant top rad. that came on the car when new. The length of the fan clutch shaft is 1 13/16ths inches measured from the face of the clutch housing that the fan blade tightens up to, to the face that bolts to the water pump shaft. Hope this makes sense. I can take a pic if you like.

Ralph

 

[Impalaguru]

Thanks for the help, Ralph. That measurement looks darn close to what I've got. It also is the same as the original I have. I've tried to find some pics of original cars but I can't see the fan shroud in the pictures. I'm not sure how it should have been.

Maybe Bob Walker can shed some light on this issue. Paging Bob Walker, Bob Walker....

Ross

 

[Impalaguru]

Thanks for the help, Bob!!bang Looks like I'll be looking for a Pontiac fan blade and clutch!!
Ross

 

[Impalaguru]

Bob, Does your fan look like this one?
http://www.ssb2.net/members/watch/enlarge.php?aid=&img=6069/100_4248.jpg
Ross

 

[Impalaguru]

Thanks for the pics, Bob!! Thats what I was wanting to see. I've spotted some fans on eBay and I think that the 60s- early 70s pontiac fans are the one you have. I've got another question, though. What is the diameter of your fan blade? The ones I've seen listed are about 19 inches. I need to remeasure my shroud.

Miles Per Gallon on a 425/409????? Well, thats not really a selling point with these cars!!! Being able to stump the guys in the new sedans IS a selling point, though!!

Thanks again for your help!

Ross

 

[Ronnie Russell]

Bob, So-o--o-o , What color is your Volvo???

 

[Tic's60]

Ross, Bob do you have a part number and a place to find it? I have one of those and well for Ross I'd send it to him for postage. It looks the same but I am no fan guru

Let me know where to look and I send the numbers I find.

 

[Impalaguru]

Thanks for the offer, Tics!!! Does your fan have the number 3947772 stamped on the blades? The inside diamter of my shroud is 19 inches so I think the pontiac fans are a no-go as they are 19". I think that the fan Bob has is a "772" chevy fan. Seems to have been used from the late 60s up into the mid-late 70s on lots of different stuff. I think they're 18" in diamter which will fit the Chevrolet shrouds.
I'm not sure what your clutch is off of, Bob. That thing is a monster!!

Oh Bob, I hope you don't have one of those little chihuahua dogs to carry arround on your arm, too!!! I would hate to see it with a pink outfit to match your volvo!!! Just kidding!!

Ross