Radiator fan upgrade

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

JeepJeepster

Full Access Member
Joined
Dec 15, 2004
Messages
8,904
Reaction score
292
Location
Dem hollers in Ky
Thought about replacing the clutch for the mechanical fan? Mine cools wonderfully on my 04 with the electric fan and mechanical fan combo. Fan roars anytime the engine is above 200F.
 

nlocascio

Full Access Member
Joined
May 6, 2014
Messages
41
Reaction score
0
Location
Arizona
But without the clutch won't it just be on all the time, killing horsepower and fuel economy at anything above idle? I have seen people replace the clutch fan with upgraded one from a Chevy model i can't remember
 

TwoBobsKJ

Full Access Member
Joined
Jan 28, 2011
Messages
2,637
Reaction score
17
Location
Northern Ohio
But without the clutch won't it just be on all the time, killing horsepower and fuel economy at anything above idle? I have seen people replace the clutch fan with upgraded one from a Chevy model i can't remember

What Jeepster is saying is replace the clutch with a different model.

On mine I went with the Severe Duty Hayden clutch rather than the standard duty. And like Jeepster's, my mechanical fan roars like a Peterbilt truck when the coolant temp gets to 200 degrees. My A/C is slightly warmer at idle or at stop lights but not much and right now it's about 90 degrees and humid enough to cut the air with a knife.

The SD clutch hasn't affected my fuel mileage - I'm on a road trip right now in Western PA and I'm averaging 22mpg's running the A/C, pushing an ARB bumper, full skids on 265/70 Duratracs. Have to get the RPM's up to around 2300 or 2400 and 74mph to get that mileage but makes for a fun drive :gr_grin:


Bob
 
Last edited:

Jbergun

Full Access Member
Joined
Jun 4, 2015
Messages
1,009
Reaction score
2
Location
Chicago
Will the severe duty fit an 02 all the cross references i have done show that its for newer kjs. From what i have seen it is a hayden 2905 is the severe but none of the sites say it fits a 2002 limited.
 

TwoBobsKJ

Full Access Member
Joined
Jan 28, 2011
Messages
2,637
Reaction score
17
Location
Northern Ohio
Will the severe duty fit an 02 all the cross references i have done show that its for newer kjs. From what i have seen it is a hayden 2905 is the severe but none of the sites say it fits a 2002 limited.

Yep, it'll fit. The shroud and mechanical fan are all the same from '02 through '07 - though not sure how many of the later KJ's actually got the HD cooling. Doesn't seem to be a very popular option in the later years.


Bob
 

TwoBobsKJ

Full Access Member
Joined
Jan 28, 2011
Messages
2,637
Reaction score
17
Location
Northern Ohio
does anyone know the pitch of the clutch fan blade?

I just read that heavy and severe duty clutch fan will only be beneficial if the fan pitch is >2.5".

http://www.compressorworks.com/Uplo... 410 FAN CLUTCHES- STANDARD HEAVY, SEVERE.PDF

I just measured the pitch on mine (the nylon fan made for gas/petrol KJ's) and it is 2.5".

For reference, the CRD KJ's came from the factory with a steel fan and the severe duty clutch. Most CRD owners over on LOST upgraded to the nylon fan us gassers got and they've experienced significant cooling improvements - the nylon fan just moves more air.

Like your link indicates, my fan comes on at startup and quits turning after a couple of minutes unless the engine is still hot from a previous drive.

Bob
 
Top