fan Clutch

S

skip hartline

Member
Sep 9, 2011
518
5
18
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
 
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.

> 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
http://www.gmcrvparts.com
1-800-752-7502
 
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
 
Which brand is on yours?

> 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:
>
 
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
 
AC Delco - Heavy Duty

> Which brand is on yours?
>

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
not really sure
--
74 Canyon Lands, FiTech,
3.7 FD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
 
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
 
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
 
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

>
> 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:
 
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
 
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

>
> 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:
 
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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