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fan Clutch [message #368310] Sun, 02 January 2022 17:36 Go to next message
skip2 is currently offline  skip2   United States
Messages: 544
Registered: September 2011
Location: Winter Haven,FL (center o...
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Senior Member
Evening all and HAPPY NEW YEAR!

I Know this has been kick around,hashed out and beat to death but has any one come up with good replacement clutch that will last for more than a couple of years. is there a good Hayden or Napa number which proves to be the most reliable when running 180 degree thermostat. Mine just works very inconsistently now after more than the normal sitting it's use to. Anyone come up with an electric clutch conversion just for the clutch not Mercedes version. I know it would almost have to be a 2 speed so it is always turning some so it doesn't block airflow when its not fully on. Any Ideal or thoughts woul be appreciated.
Skip Hartline


74 Canyon Lands, FiTech, 3.7 FD LSD, Manny Tranny, Springfield Distributor, 2001 Chevy Tracker Ragtop Towd
[GMCnet] Re: fan Clutch [message #368319 is a reply to message #368310] Sun, 02 January 2022 22:37 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
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Senior Member
I have been running the Mercedes electric fan clutch using the box that Tom
Pryor has designed to make it work for most application.
The fan pulls in more air than the original and can be noisy, so Tom has
Speed control to work at 70%
Wee have sold about 20 units.

On Sun, Jan 2, 2022 at 3:36 PM Skip Hartline wrote:

> Evening all and HAPPY NEW YEAR!
>
> I Know this has been kick around,hashed out and beat to death but has any
> one come up with good replacement clutch that will last for more than a
> couple of years. is there a good Hayden or Napa number which proves to be
> the most reliable when running 180 degree thermostat. Mine just works very
> inconsistently now after more than the normal sitting it's use to. Anyone
> come up with an electric clutch conversion just for the clutch not Mercedes
> version. I know it would almost have to be a 2 speed so it is always
> turning some so it doesn't block airflow when its not fully on. Any Ideal or
> thoughts woul be appreciated.
> Skip Hartline
> --
> 74 Canyon Lands, FiTech,
> 3.7 FD, Manny Tranny,
> Springfield Distributor,
> 2001 Chevy Tracker Ragtop Towd
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>


--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: fan Clutch [message #368329 is a reply to message #368310] Mon, 03 January 2022 08:58 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Whatever you do stay away for the Hayden clutch. They changed the temperature sensor years ago to make them come on too early and the engineers bragged about it to me. I can not remember the number of free ones they sent to me until we figured out the sensor issue.

I advise you go with a Heavy duty (NOT SEVERE DUTY) clutch as near to OEM as possible. Mine has been on for about 15 years with no problems. At the time, I also worked with the Delco engineers to determine what clutch to use that matched the OEM specs anf for fan diameter and pitch. Read some of my past postings on this for more info. I can not give you info on other brands as I have no first hand experience with them.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: fan Clutch [message #368331 is a reply to message #368310] Mon, 03 January 2022 09:31 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
I installed a Napa 271303 in september of 2020. It has worked well since, summer of 2021 was a hot one!

Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
[GMCnet] Re: fan Clutch [message #368333 is a reply to message #368329] Mon, 03 January 2022 10:05 Go to previous messageGo to next message
Lawrence Belland is currently offline  Lawrence Belland   United States
Messages: 11
Registered: May 2021
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Junior Member
Which brand is on yours?

On Mon, Jan 3, 2022 at 6:59 AM Ken Burton wrote:

> Whatever you do stay away for the Hayden clutch. They changed the
> temperature sensor years ago to make them come on too early and the
> engineers
> bragged about it to me. I can not remember the number of free ones they
> sent to me until we figured out the sensor issue.
>
> I advise you go with a Heavy duty (NOT SEVERE DUTY) clutch as near to OEM
> as possible. Mine has been on for about 15 years with no problems. At the
> time, I also worked with the Delco engineers to determine what clutch to
> use that matched the OEM specs anf for fan diameter and pitch. Read some of
> my past postings on this for more info. I can not give you info on other
> brands as I have no first hand experience with them.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
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Re: fan Clutch [message #368339 is a reply to message #368310] Mon, 03 January 2022 16:15 Go to previous messageGo to next message
Greg C. is currently offline  Greg C.   United States
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Registered: October 2019
Location: Knoxville, TN
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Senior Member
I installed a NAPA 271301 in October of 2020. So far, it is working fine. It runs about a minute and a half at cold start up, doesn't come on again until my Autometer temp gauge hits about 205. It then runs until the temp gauge reads about 180 or so, and kicks off. I have a stock 1977 403 with 195 degree Robert Shaw thermostat, newly re-cored factory radiator, and Olds aluminum intake manifold running the factory Quadrajet.


Greg Crawford KM4ZCR Knoxville, TN "Ruby Sue" 1977 Royale Rear Bath 403 Engine American Eagle Wheels Early Version Alex Sirum Quad bags
Re: [GMCnet] Re: fan Clutch [message #368341 is a reply to message #368333] Mon, 03 January 2022 18:33 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
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AC Delco - Heavy Duty

Lawrence Belland wrote on Mon, 03 January 2022 10:05
Which brand is on yours?

On Mon, Jan 3, 2022 at 6:59 AM Ken Burton wrote:




Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Re: fan Clutch [message #368342 is a reply to message #368333] Mon, 03 January 2022 18:53 Go to previous messageGo to next message
skip2 is currently offline  skip2   United States
Messages: 544
Registered: September 2011
Location: Winter Haven,FL (center o...
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not really sure

74 Canyon Lands, FiTech, 3.7 FD LSD, Manny Tranny, Springfield Distributor, 2001 Chevy Tracker Ragtop Towd
Re: fan Clutch [message #368344 is a reply to message #368310] Tue, 04 January 2022 09:40 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
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Senior Member
The interchange lists 3 duty level numbers for NAPA clutches. I think the middle number is heavy, not severe duty. I have had good results with NAPA made in USA clutches in other applications. Some may be Mexico now.
Greg C I don’t understand how you are getting a 180 reading with a 195 thermostat. The thermostat sets the minimum operating temp, which should be 195. Unless your aftermarket temp gauge is reading radiator rather than engine coolant temp.


John Lebetski
Woodstock, IL
77 Eleganza II
Re: fan Clutch [message #368355 is a reply to message #368310] Tue, 04 January 2022 21:10 Go to previous messageGo to next message
Greg C. is currently offline  Greg C.   United States
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Location: Knoxville, TN
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I don't know myself. The sensor is in the intake manifold, passenger side, where the tvs used to be. It stays below 195 most of the time. My heater outlet temp is 145 degrees sitting in the driveway in 50 degree weather. I have an aluminum intake which may shed heat quicker.

Greg Crawford KM4ZCR Knoxville, TN "Ruby Sue" 1977 Royale Rear Bath 403 Engine American Eagle Wheels Early Version Alex Sirum Quad bags
[GMCnet] Re: fan Clutch [message #368356 is a reply to message #368355] Tue, 04 January 2022 21:51 Go to previous messageGo to next message
stu@97381.com, Emery  is currently offline  stu@97381.com, Emery   United States
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You might find that the proper location of the temperature sensor is on the drivers side to the left of the thermostat housing. That location is more in the flow path of the coolant. What sensor do you have there or is it plugged off?

Emery Stora
77 Kingsley
Frederick CO


> On Jan 4, 2022, at 8:11 PM, Greg Crawford wrote:
>
> I don't know myself. The sensor is in the intake manifold, passenger side, where the tvs used to be. It stays below 195 most of the time. My heater
> outlet temp is 145 degrees sitting in the driveway in 50 degree weather. I have an aluminum intake which may shed heat quicker.
> --
> Greg Crawford
> KM4ZCR
> Knoxville, TN
>
> "Ruby Sue"
> 1977 Royale
> Rear Bath
> 403 Engine
> American Eagle Wheels
> Early Version Alex Sirum Quad bags
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Re: fan Clutch [message #368373 is a reply to message #368310] Thu, 06 January 2022 15:44 Go to previous messageGo to next message
Greg C. is currently offline  Greg C.   United States
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Location: Knoxville, TN
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Yes, I have the factory sender there. I like redundancy when possible, and the recommended style factory sender gives me 1/2 gauge normal, which seems to correspond roughly with the Autometer. I don't know why it drops to 180 degrees or so with a 195 degree thermostat when the fan runs. But it does not stay there long before it's back up to 195. I have checked the T-stat housing with my infrared thermometer, and it will open at about 195 or so. I also stove top tested the t-stat in boiling water for operation before installing. I guess I could take some more readings, but it takes a lot of time to get the engine up to 205 at 1000 rpm in the driveway. Especially now with cold weather. Possibly something to do with the cooling water routing is causing the difference between the Autometer reading and the thermostat's range.

Greg Crawford KM4ZCR Knoxville, TN "Ruby Sue" 1977 Royale Rear Bath 403 Engine American Eagle Wheels Early Version Alex Sirum Quad bags
[GMCnet] Re: fan Clutch [message #368379 is a reply to message #368373] Fri, 07 January 2022 13:26 Go to previous messageGo to next message
stu@97381.com, Emery  is currently offline  stu@97381.com, Emery   United States
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That sounds normal. It is not uncommon for the temperature to drop 10 or 15 degrees when the thermostat opens with the fan running. So a drop from 195 to 180 should not be a concern.

Emery Stora
77 Kingsley
Frederick CO

> On Jan 6, 2022, at 2:46 PM, Greg Crawford wrote:
>
> Yes, I have the factory sender there. I like redundancy when possible, and the recommended style factory sender gives me 1/2 gauge normal, which seems
> to correspond roughly with the Autometer. I don't know why it drops to 180 degrees or so with a 195 degree thermostat when the fan runs. But it does
> not stay there long before it's back up to 195. I have checked the T-stat housing with my infrared thermometer, and it will open at about 195 or so. I
> also stove top tested the t-stat in boiling water for operation before installing. I guess I could take some more readings, but it takes a lot of time
> to get the engine up to 205 at 1000 rpm in the driveway. Especially now with cold weather. Possibly something to do with the cooling water routing is
> causing the difference between the Autometer reading and the thermostat's range.
> --
> Greg Crawford
> KM4ZCR
> Knoxville, TN
>
> "Ruby Sue"
> 1977 Royale
> Rear Bath
> 403 Engine
> American Eagle Wheels
> Early Version Alex Sirum Quad bags
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Re: fan Clutch [message #368391 is a reply to message #368310] Sat, 08 January 2022 18:25 Go to previous message
Greg C. is currently offline  Greg C.   United States
Messages: 224
Registered: October 2019
Location: Knoxville, TN
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Senior Member
Emery, when I think about it, in my stove top test, it took 30-45 seconds for the thermostat to react and fully open/close once it reached its open/close temperatures. It makes perfect sense that the coolant can drop below the t-stat's close temperature before the t-stat has time to actually fully close when that big fan is running. That would explain my gauge reading 180 for a bit before climbing back up.

I do know that the new re-cored radiator is definitely working better than the old one. Thank you for your input!


Greg Crawford KM4ZCR Knoxville, TN "Ruby Sue" 1977 Royale Rear Bath 403 Engine American Eagle Wheels Early Version Alex Sirum Quad bags
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