Convert to Clutch fan - Chevelle Tech
Heating & Cooling Heating, cooling and air conditioning Sponsored by:Cold-Case Aluminum Radiators

 16Likes
Reply
 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 25 (permalink) Old Aug 17th, 19, 1:19 PM Thread Starter
Lifetime Premium Member
Rob
 
Join Date: Mar 2015
Location: Denver
Posts: 975
Convert to Clutch fan

1969 El Camino 350 with direct drive 4 blade fan. NON AC car.

Had an earlier post but it's so.old I can't update it.

https://www.chevelles.com/forums/ind...topics/1052625

So I'm putting a radiator in might as well finish this job.

New parts

3947772 Fan
2705 Hayden Thermal Fan Clutch

Does that sound right?
The fan is 18, my shroud 19.5.

I'm concerned about the fan. Ground Up sells a setup with different fan?

ROB

69 El Camino


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
robpp is offline  
Sponsored Links
Advertisement
 
post #2 of 25 (permalink) Old Aug 17th, 19, 2:17 PM
Lifetime Premium Member
Cory
 
Join Date: Mar 2011
Location: Wimberley, TX (SW of Austin)
Posts: 4,660
Re: Convert to Clutch fan

The Hayden 2705 appears to be a STANDARD DUTY clutch which I prefer after going through 2 HEAVY DUTY clutches that made my 72 Cutlass sound like a school bus.



That experience was with a 19" - 6 blade fan.
427L88 and robpp like this.
dream66 is offline  
post #3 of 25 (permalink) Old Aug 17th, 19, 2:48 PM
Lifetime Premium Member
Al
 
Join Date: Apr 2011
Location: SO CAL...Huntington Beach and Rancho Cucamonga
Posts: 5,190
Garage
Re: Convert to Clutch fan

That fan size and shroud will work correctly. It will give you 3/4 inch clearance all around. It's been a while since I had a 69 small block, but I think I remember a 1-inch spacer between the water pump and fan clutch. You can check this visually when you have the parts the fan tip blades should be half in and half out of the shroud. Your motor mounts need to be in good condition.

If someone knows for sure if the 69 small blocks had a spacer with the HD fan and clutch, please verify.

The standard-duty fan clutch should work fine in your application since you are not running a/c.
Kirk's67SS likes this.
DUTCH MAX HEADWORK is offline  
 
post #4 of 25 (permalink) Old Aug 17th, 19, 5:31 PM
Lifetime Premium Member
Al
 
Join Date: Apr 2011
Location: SO CAL...Huntington Beach and Rancho Cucamonga
Posts: 5,190
Garage
Re: Convert to Clutch fan

When you look at the 772 fan you are going to purchase, it should have the curved blade tips on the end. This makes the fan less noisy and fits in the fan shroud better. I've seen repop 772's being sold without the curved tips, this is incorrect and may hit the shroud. Depending on variances in the vehicle or other issues, you may have to align the fan shroud by elongating screw holes. Saggy engine mounts may cause fan contact at the bottom of the shroud.

Top attachment has squared tips, lower attachment is original 772 and has the curved blades.
Attached Thumbnails
Click image for larger version

Name:	repop 3947772 fan w no curved blades.jpg
Views:	16
Size:	169.4 KB
ID:	600862  
Attached Images
 
DUTCH MAX HEADWORK is offline  
post #5 of 25 (permalink) Old Aug 17th, 19, 6:30 PM
Tech Team
 
Join Date: Sep 2015
Location: PNW
Posts: 917
Garage
Re: Convert to Clutch fan

This is the repop I use ebay link

'69 Malibu
Not2Fast is offline  
post #6 of 25 (permalink) Old Aug 17th, 19, 10:53 PM
Lifetime Premium Member
Tom
 
Join Date: Oct 2006
Location: Firestone, CO
Posts: 1,260
Re: Convert to Clutch fan

I have a new repop of the 772 fan from Dynacorn that I'm not going to use if you're interested.

70 Camino...Roller

69 Malibu Stock 307, Reverse Manual TH350, 4,500 Stall Edge Converter, 4.56 Spool 35 Spline 12 Bolt

76 C20 VortecPro 496 628HP 655 lb/ft TH400 Edge Converter, 4.10 14 bolt
Tommy the Cat is offline  
post #7 of 25 (permalink) Old Aug 19th, 19, 3:46 PM Thread Starter
Lifetime Premium Member
Rob
 
Join Date: Mar 2015
Location: Denver
Posts: 975
Re: Convert to Clutch fan

Quote:
Originally Posted by DUTCH MAX HEADWORK View Post
When you look at the 772 fan you are going to purchase, it should have the curved blade tips on the end. This makes the fan less noisy and fits in the fan shroud better. I've seen repop 772's being sold without the curved tips, this is incorrect and may hit the shroud. Depending on variances in the vehicle or other issues, you may have to align the fan shroud by elongating screw holes. Saggy engine mounts may cause fan contact at the bottom of the shroud.

OK I do have new motor mounts about 4000 miles ago.

Top attachment has squared tips, lower attachment is original 772 and has the curved blades.
OK. I bought this one https://www.jegs.com/i/OER/691/39477...xoCO5QQAvD_BwE

Quote:
Originally Posted by DUTCH MAX HEADWORK View Post
That fan size and shroud will work correctly. It will give you 3/4 inch clearance all around. It's been a while since I had a 69 small block, but I think I remember a 1-inch spacer between the water pump and fan clutch. You can check this visually when you have the parts the fan tip blades should be half in and half out of the shroud. Your motor mounts need to be in good condition.

If someone knows for sure if the 69 small blocks had a spacer with the HD fan and clutch, please verify.

The standard-duty fan clutch should work fine in your application since you are not running a/c.
Yeah once I have everything in hand I will NEXT figure out what fan spacer size I may need.

ROB

69 El Camino


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
robpp is offline  
post #8 of 25 (permalink) Old Aug 19th, 19, 4:59 PM Thread Starter
Lifetime Premium Member
Rob
 
Join Date: Mar 2015
Location: Denver
Posts: 975
I have a new problem.

The big hole in the fan IS TOO SMALL to fit the clutch through. By like 3/16. its not just a smidge.
Attached Thumbnails
Click image for larger version

Name:	IMG_20190819_140804259_1566245385567.jpg
Views:	16
Size:	2.68 MB
ID:	601044  

ROB

69 El Camino


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
robpp is offline  
post #9 of 25 (permalink) Old Aug 19th, 19, 5:39 PM Thread Starter
Lifetime Premium Member
Rob
 
Join Date: Mar 2015
Location: Denver
Posts: 975
Re: Convert to Clutch fan

ok i found this thread about the same issue as above.

https://www.chevelles.com/forums/32-...2-fan-why.html

I bought from Jegs and when i NOW look at reviews someone posted it didnt fit.

part number has the 691 in front of it.

So I put in for a return with Jegs

and ordered the correct one from eBay
427L88 likes this.

ROB

69 El Camino


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
robpp is offline  
post #10 of 25 (permalink) Old Aug 19th, 19, 6:55 PM
Tech Team
Harry
 
Join Date: Jan 2011
Location: Los Angeles
Posts: 310
Re: Convert to Clutch fan

I use the original 772, 7 blade fan with the curved, round ends, with the hayden heavy duty fan clutch, and original fan shroud. I also use a Griffin aluminum radiator. This works very well in over 100 deg. heat with the air conditioning on full blast.

Harry
1970 Chevelle SS396 (408), Fathom Blue,
Original Block & Forged Crank, KB Pistons, Edelbrock 6045 Heads,Comp Cam 292H, March Serpentine, RPM AirGap,750HP,100hp Nitrous
A/F Wideband,Tremec TKO 600, 12 bolt,
30 spline Moser Axles, Richmond 3:73's, Hotchkis control arms, swaybars, springs, Wilwood 12" rotors D/S, 4 piston calipers
hjdca is offline  
post #11 of 25 (permalink) Old Aug 19th, 19, 11:35 PM
Lifetime Premium Member
leo
 
Join Date: Oct 2003
Location: Southwest Florida
Posts: 13,228
Re: Convert to Clutch fan

Rob, you probably could have gotten the correct fan clutch at your loca NAPA store!

Leo Paugh
Maryland Chevelle Club #017
A.C.E.S.#3731
progress has little to do with speed, but lots to do with direction

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
LeoP is offline  
post #12 of 25 (permalink) Old Aug 20th, 19, 1:04 AM
Lifetime Premium Member
Al
 
Join Date: Apr 2011
Location: SO CAL...Huntington Beach and Rancho Cucamonga
Posts: 5,190
Garage
Re: Convert to Clutch fan

Quote:
Originally Posted by robpp View Post
I have a new problem.

The big hole in the fan IS TOO SMALL to fit the clutch through. By like 3/16. its not just a smidge.
Basstards! They don't offer any dimensions for the fan besides 18".
DUTCH MAX HEADWORK is offline  
post #13 of 25 (permalink) Old Aug 20th, 19, 12:46 PM Thread Starter
Lifetime Premium Member
Rob
 
Join Date: Mar 2015
Location: Denver
Posts: 975
Quote:
Originally Posted by LeoP View Post
Rob, you probably could have gotten the correct fan clutch at your loca NAPA store!
Leo I see someone listed a Murray 2710 that fit the fan with small hole. 3" bolt circle. This what you are referring to? Thanks.

I am returning the Jegs fan instead because I got free return shipping after 3 phone calls.

I have to say I haven't found a parts store worth a **** in Denver area yet. So I would get no help there.

Quote:
Originally Posted by DUTCH MAX HEADWORK View Post
Quote:
Originally Posted by robpp View Post
I have a new problem.

The big hole in the fan IS TOO SMALL to fit the clutch through. By like 3/16. its not just a smidge.
<img src="https://www.chevelles.com/forums/images/smilies/angry.gif" border="0" alt="" title="Angry" class="inlineimg" /> Basstards! <img src="https://www.chevelles.com/forums/images/smilies/noway.gif" border="0" alt="" title="Noway" class="inlineimg" /> They don't offer any dimensions for the fan besides 18".
Yup. Even the TECH GUY at Jegs seemed puzzled by not finding the bolt circle dimensions. I kept pointing to this Forum as well as the one REVIEW that said it didn't fit.

So the problem is I need a 3.25 bolt circle and the fan from JEGS was 3.0.

I tell you this simple little project has been nothing but painful.

My next challenge is finding hardware.

I need 4 simple little bolts. 5/16-18 x 5/8 hex. Ace seems to go from 1/2 to 3/4 L. 3/4 is too long for clutch. 1/2 looks too short. Google.......Home Depot has them. 1 local store has 11. I order over internet rather than drive 10 miles, it was 99 yesterday, anyway order cancelled. None in stock. Today I'm working on the shroud. Only 96 and 15% feels like 90 LOL But I have the Fastenal store in my sights.....fir 4 bolts. Holes depth in clutch only a bit more than half inch. Or I'll use the long ones with an extra washer or 2.



The next step is determining what length spacer I may need for the clutch to water pump for perfect fan placement.
Then finding said spacer and hardware .


Thanks for all the help ! Cheers

ROB

69 El Camino


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
robpp is offline  
post #14 of 25 (permalink) Old Aug 20th, 19, 1:18 PM
Lifetime Premium Member
Tom
 
Join Date: Oct 2006
Location: Firestone, CO
Posts: 1,260
Re: Convert to Clutch fan

I bought my hardware from Ground Up. I don't have mine installed yet and won't need them for a while. If you're in a bind you could have mine and order new ones from Ground Up to replace them.

You shouldn't need a spacer with the clutch.

70 Camino...Roller

69 Malibu Stock 307, Reverse Manual TH350, 4,500 Stall Edge Converter, 4.56 Spool 35 Spline 12 Bolt

76 C20 VortecPro 496 628HP 655 lb/ft TH400 Edge Converter, 4.10 14 bolt
Tommy the Cat is offline  
post #15 of 25 (permalink) Old Aug 20th, 19, 2:02 PM
Tech Team
Harry
 
Join Date: Jan 2011
Location: Los Angeles
Posts: 310
Re: Convert to Clutch fan

Quote:
Originally Posted by robpp View Post
OK. I bought this one https://www.jegs.com/i/OER/691/39477...xoCO5QQAvD_BwE



Yeah once I have everything in hand I will NEXT figure out what fan spacer size I may need.
Here is a pic of my SS396 Chevelle with the 772 fan, Hayden heavy duty fan clutch, stock shroud, griffin radiator, long water pump, no spacer with A/C. The fan is in the perfect spot for best cooling. Try to achieve this kind of spacing for best cooling results.

LeoP and Chevymec like this.

Harry
1970 Chevelle SS396 (408), Fathom Blue,
Original Block & Forged Crank, KB Pistons, Edelbrock 6045 Heads,Comp Cam 292H, March Serpentine, RPM AirGap,750HP,100hp Nitrous
A/F Wideband,Tremec TKO 600, 12 bolt,
30 spline Moser Axles, Richmond 3:73's, Hotchkis control arms, swaybars, springs, Wilwood 12" rotors D/S, 4 piston calipers
hjdca is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevelle Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address. Note, you will be sent a confirmation request to this address.

Email Address:
OR

Log-in










Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome