Engine/Transmission (1994 - 1998) Fan engagement nearly constant

[Vaughn MacKenzie]

The fan on my '96 engages readily when temps get in the low 90s and above, especially with AC on. To me it seems to be on the aggressive side. Engine temps are fine, cleaned my radiator good not too many miles ago and coolant & T-stat done within the last year. Today driving down the freeway at 70 it was fully engaged all the time, which I noticed it does when it's about 100 or higher (it was 100 today). When this happens it seems to be "stuck" in full engagement until the ambient temps drop below 90. Anyway I'm thinkin' it's time for a new fan clutch.



Vaughn

 

[wcjp]

Try using an infrared thermometer on the radiator. While running all sectors of the radiator temps should be constant. Meaning the top third should be the same. The middle the same and the bottom the same. This would eliminate the radiator as a suspect.

 

[Vaughn MacKenzie]

Interesting tip, thanks Bill. I have an infrared thermometer at work so I'll give it a try.

 

[WDaniels]

Vaughn,

Sounds like the viscous fluid in the fan is going bad or the clutch in it is toast. I used to have a spare but chucked it when I moved.

WD

 

[DieselDoghouse]

You can get these clutches aftermarket (NAPA, et al) to my knowledge most are still lifetime warranty.

 

[Vaughn MacKenzie]

Today it was working more normally, it didn't stay on all the time, cycled on about 1/3 of the time, so I guess it has a mind of its own. It was right at 100 again today, had the AC maxed all the way home after playing softball in the heat . . . I was dying!

 

[Matt42]

The fan on my '96 engages readily when temps get in the low 90s and above, especially with AC on. To me it seems to be on the aggressive side. Engine temps are fine, cleaned my radiator good not too many miles ago and coolant & T-stat done within the last year. Today driving down the freeway at 70 it was fully engaged all the time, which I noticed it does when it's about 100 or higher (it was 100 today). When this happens it seems to be "stuck" in full engagement until the ambient temps drop below 90. Anyway I'm thinkin' it's time for a new fan clutch.



Vaughn

Actually, this sounds like pretty normal behaviour based on Phoenix temps.

 

[Howard Durand]

I just completed a trip from Soap Lake WA to western Nebraska and back. Ambient temperatures were early spring cool. My engine coolant temperature seldom rose above about 150 or 160 degrees. During a heavy pull up some of the long grades, it actually rose to 190 or so.

It sounded like the fan was continuously on and off. On the long pulls it came on and stayed on until coolant temperatures backed off.

I'll replace the clutch and see what happens.