Fan Shroud? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Hubscrub · 07-19-2010, 11:01 PM

i have a 71 chevy and i am going to put a shroud and 7 blade clutch fan on it to get rid of the flex fan will a standard shroud work since my engine is in the back position like a inline would be, or do i need a 4x4 shroud i have been told the 4x4 shroud is deeper thanks

68GMCCustom · 07-20-2010, 12:06 AM

you would be better off putting a 1" or longer extension (over what you have now) getting the fan closer to the radiator...then a standard shroud would fit and the fan would pull more air thru the radiator.

storm9c1 · 07-20-2010, 10:54 AM

Quote:

Originally Posted by 68GMCCustom

you would be better off putting a 1" or longer extension (over what you have now) getting the fan closer to the radiator...then a standard shroud would fit and the fan would pull more air thru the radiator.

+1. Get a clutch with a long extension neck too. You can look at the Hayden catalog (online) and find a clutch, maybe for another vehicle, with the same bolt and pilot hole dimensions (which are the same on many old domestic vehicles), but with a longer neck. The catalog lists all of the dimensions, which is cool.

Most stores like Advance Auto can lookup those part numbers directly. The temperature parameters are the same, so you don't have to worry about that. I've done this before on custom engine jobs.

**Stocker** · 07-20-2010, 12:16 PM

fwiw, my 4x4 shroud measures 9" from the front lip to the fan opening. The fan is right where it should be. I measure 6" from the radiator to the fan clutch -- and about 9 1/2" from the radiator to the mounting surface on the water pump pulley.

68GMCCustom · 07-20-2010, 02:23 PM

yes...some vehicle designs required the fan to be further back from the radiator...and they have special "deep" shrouds to accomodate. Its not the prefered scenario tho... as the closer the fan is to the radiator...the more efficient it is at moving (pulling/pushing) air through the radiator.

storm9c1 · 07-20-2010, 02:48 PM

Quote:

Originally Posted by 68GMCCustom

yes...some vehicle designs required the fan to be further back from the radiator...and they have special "deep" shrouds to accomodate. Its not the prefered scenario tho... as the closer the fan is to the radiator...the more efficient it is at moving (pulling/pushing) air through the radiator.

Not only that, but a thermal fan clutch needs to be close to the radiator so that it can receive the right temperature (for proper lockup). IMO, once you move the clutch over 1" away, you may have overheating problems. Try to keep the fan as close to the radiator as possible by using a fan clutch with a longer shaft or use a spacer behind it.

Hubscrub · 07-20-2010, 05:58 PM

thanks all for the help i will do some looking and see what i can find

**Stocker** · 07-20-2010, 08:58 PM

Quote:

Originally Posted by 68GMCCustom

yes...some vehicle designs required the fan to be further back from the radiator...and they have special "deep" shrouds to accomodate. Its not the prefered scenario tho... as the closer the fan is to the radiator...the more efficient it is at moving (pulling/pushing) air through the radiator.

I don't think it matters much (within reason) if the shroud is correctly designed.... the fan will pull all possible air through the radiator.

Quote:

Originally Posted by storm9c1

Not only that, but a thermal fan clutch needs to be close to the radiator so that it can receive the right temperature (for proper lockup). IMO, once you move the clutch over 1" away, you may have overheating problems.

Maybe.... but as I posted above, my clutch fan is 6" from the radiator (factory design) and has the oem shroud. In 33 years (that I know of) it has not had an overheating problem. Well, it did once, when I temporarily installed a flex fan...

oldblue1968chevy · 07-20-2010, 11:02 PM

hey hub, ATT had a shroud awhile back I think he said he had one at least, may check his craiglist stuff out..

mexgrhd68 · 07-22-2010, 09:19 PM

Quote:

Originally Posted by oldblue1968chevy

hey hub, ATT had a shroud awhile back I think he said he had one at least, may check his craiglist stuff out..

eh, u dont need it, ive been running mine in that position for around 15 years..305/350 combo.

**WIDESIDE72** · 07-22-2010, 09:30 PM

I thought I had a bright idea by mounting an 80's clutch fan in place of the stocker on my Army truck budget build. Only problem is, the clutch fan is a larger diameter and won't fit in the shroud...

oldblue1968chevy · 07-22-2010, 09:51 PM

yeah..lol my late 70's motor's fan wouldnt fit in the 67-72 shroud..lol good thing i had a parts truck

Hubscrub · 07-22-2010, 10:02 PM

how much did it like from fitting alot?

bjinx · 07-23-2010, 01:23 AM

I am using a stock shroud on my '70 with a Flow Cooler short pump and an AC Delco fan clutch I got from ROCKAUTO. The engine used to run about 200* in the summer, the delco fan clutch brought it down to 185-190,made all the difference in the world. They are alot cheaper at Rockauto.com

oldblue1968chevy · 07-23-2010, 11:11 AM

it was DANG close hub, but it just didnt fit

I got the fan from my 72 350ci parts truck worked good!

07-19-2010, 11:01 PM	#1
Hubscrub Cruzin Join Date: Dec 2009 Location: on the road Posts: 2,835	Fan Shroud? i have a 71 chevy and i am going to put a shroud and 7 blade clutch fan on it to get rid of the flex fan will a standard shroud work since my engine is in the back position like a inline would be, or do i need a 4x4 shroud i have been told the 4x4 shroud is deeper thanks Attached Images __________________ Lime Wife's 67https://www.google.com/url?sa=t&rct=...wZEMODaS2d94u8 Back to the Fifties 59 https://www.google.com/url?sa=t&rct=...NAeStpydfrcj_U Proverbs 3:5,6 "Thanks to the Interstate Highway System, it is now possible to travel across the country from coast to coast without seeing anything."Charles Kuralt In memory of our first baby daughter, daddy and mommy love you. Danica Grace 6/26/14

07-20-2010, 12:06 AM	#2
68GMCCustom Truck and auto performance nut Join Date: Feb 2007 Location: McKinney,Texas Posts: 3,848	Re: Fan Shroud? you would be better off putting a 1" or longer extension (over what you have now) getting the fan closer to the radiator...then a standard shroud would fit and the fan would pull more air thru the radiator. __________________ Kurt - '68 GMC short step - NIB '09 LY6 6.0L crate motor w/mods, NIB '12 crate 4L85e w/billet 3k stall Circle D, 3.73 posi 12 bolt, DynaTech f-swap headers, 3/4 drop, handling mods, etc. - my toy '72 Chevy LWB C-10 Highlander - 350/350 ps/pb/tilt/ac - not original but close '06 Chevy TrailBlazerSS - LS2/4L70e - little black hot rod SUV - my DD '18 Kia Sorento - wife's econo-driver '95 Chevy S10 - reg cab shortbed, LS, 4.3, auto... my '68's powertrain and chassis build -links broken A surprise phase - carb to efi -links broken

07-20-2010, 12:16 PM	#4
Stocker 20' Daredevil (Ret) Join Date: May 2003 Location: Jefferson State Posts: 13,728	Re: Fan Shroud? fwiw, my 4x4 shroud measures 9" from the front lip to the fan opening. The fan is right where it should be. I measure 6" from the radiator to the fan clutch -- and about 9 1/2" from the radiator to the mounting surface on the water pump pulley. __________________ - Mike - 1972 K20 LWB 350/350/205 RIP El Jay

07-20-2010, 02:23 PM	#5
68GMCCustom Truck and auto performance nut Join Date: Feb 2007 Location: McKinney,Texas Posts: 3,848	Re: Fan Shroud? yes...some vehicle designs required the fan to be further back from the radiator...and they have special "deep" shrouds to accomodate. Its not the prefered scenario tho... as the closer the fan is to the radiator...the more efficient it is at moving (pulling/pushing) air through the radiator. __________________ Kurt - '68 GMC short step - NIB '09 LY6 6.0L crate motor w/mods, NIB '12 crate 4L85e w/billet 3k stall Circle D, 3.73 posi 12 bolt, DynaTech f-swap headers, 3/4 drop, handling mods, etc. - my toy '72 Chevy LWB C-10 Highlander - 350/350 ps/pb/tilt/ac - not original but close '06 Chevy TrailBlazerSS - LS2/4L70e - little black hot rod SUV - my DD '18 Kia Sorento - wife's econo-driver '95 Chevy S10 - reg cab shortbed, LS, 4.3, auto... my '68's powertrain and chassis build -links broken A surprise phase - carb to efi -links broken

07-20-2010, 05:58 PM	#7
Hubscrub Cruzin Join Date: Dec 2009 Location: on the road Posts: 2,835	Re: Fan Shroud? thanks all for the help i will do some looking and see what i can find __________________ Lime Wife's 67https://www.google.com/url?sa=t&rct=...wZEMODaS2d94u8 Back to the Fifties 59 https://www.google.com/url?sa=t&rct=...NAeStpydfrcj_U Proverbs 3:5,6 "Thanks to the Interstate Highway System, it is now possible to travel across the country from coast to coast without seeing anything."Charles Kuralt In memory of our first baby daughter, daddy and mommy love you. Danica Grace 6/26/14

07-20-2010, 11:02 PM	#9
oldblue1968chevy Grandpa in the rustmobile... Join Date: Nov 2008 Location: Spokane WA/Viola TN Posts: 11,422	Re: Fan Shroud? hey hub, ATT had a shroud awhile back I think he said he had one at least, may check his craiglist stuff out.. __________________ John Goose-1968 C10 355,9.32-1CR, Vortec Heads ,262 voodoo, 3.73:1 3OTT (HS ride/beater/farm truck) http://67-72chevytrucks.com/vboard/s...d.php?t=317684 Grams 53-1953 Chevrolet Belair http://67-72chevytrucks.com/vboard/s...=1#post4327784 1969 Chevy C10 Shortbed 4.5/6?" Frame off resto http://67-72chevytrucks.com/vboard/s...d.php?t=548136 1999 Toyota Tacoma 4x4

07-22-2010, 09:30 PM	#11
WIDESIDE72 Senior Member Join Date: Aug 2008 Location: Cedar Park, Texas Posts: 7,500	Re: Fan Shroud? I thought I had a bright idea by mounting an 80's clutch fan in place of the stocker on my Army truck budget build. Only problem is, the clutch fan is a larger diameter and won't fit in the shroud...

07-22-2010, 09:51 PM	#12
oldblue1968chevy Grandpa in the rustmobile... Join Date: Nov 2008 Location: Spokane WA/Viola TN Posts: 11,422	Re: Fan Shroud? yeah..lol my late 70's motor's fan wouldnt fit in the 67-72 shroud..lol good thing i had a parts truck __________________ John Goose-1968 C10 355,9.32-1CR, Vortec Heads ,262 voodoo, 3.73:1 3OTT (HS ride/beater/farm truck) http://67-72chevytrucks.com/vboard/s...d.php?t=317684 Grams 53-1953 Chevrolet Belair http://67-72chevytrucks.com/vboard/s...=1#post4327784 1969 Chevy C10 Shortbed 4.5/6?" Frame off resto http://67-72chevytrucks.com/vboard/s...d.php?t=548136 1999 Toyota Tacoma 4x4

07-22-2010, 10:02 PM	#13
Hubscrub Cruzin Join Date: Dec 2009 Location: on the road Posts: 2,835	Re: Fan Shroud? how much did it like from fitting alot? __________________ Lime Wife's 67https://www.google.com/url?sa=t&rct=...wZEMODaS2d94u8 Back to the Fifties 59 https://www.google.com/url?sa=t&rct=...NAeStpydfrcj_U Proverbs 3:5,6 "Thanks to the Interstate Highway System, it is now possible to travel across the country from coast to coast without seeing anything."Charles Kuralt In memory of our first baby daughter, daddy and mommy love you. Danica Grace 6/26/14

07-23-2010, 01:23 AM	#14
bjinx Registered User Join Date: May 2010 Location: Houston, Texas Posts: 6	Re: Fan Shroud? I am using a stock shroud on my '70 with a Flow Cooler short pump and an AC Delco fan clutch I got from ROCKAUTO. The engine used to run about 200* in the summer, the delco fan clutch brought it down to 185-190,made all the difference in the world. They are alot cheaper at Rockauto.com

07-23-2010, 11:11 AM	#15
oldblue1968chevy Grandpa in the rustmobile... Join Date: Nov 2008 Location: Spokane WA/Viola TN Posts: 11,422	Re: Fan Shroud? it was DANG close hub, but it just didnt fit I got the fan from my 72 350ci parts truck worked good! __________________ John Goose-1968 C10 355,9.32-1CR, Vortec Heads ,262 voodoo, 3.73:1 3OTT (HS ride/beater/farm truck) http://67-72chevytrucks.com/vboard/s...d.php?t=317684 Grams 53-1953 Chevrolet Belair http://67-72chevytrucks.com/vboard/s...=1#post4327784 1969 Chevy C10 Shortbed 4.5/6?" Frame off resto http://67-72chevytrucks.com/vboard/s...d.php?t=548136 1999 Toyota Tacoma 4x4



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