Kennedy Fan Clutch Question ??

[Billy V]

I have all the cooling mods done, 9 blade steel fan w/ Kennedy Fan clutch, HO water pump, along with a new oversized radiator. I am running two GM 195 deg. thermostats.

My fan clutch kicks in quite a bit now. Is this normal with my set up??
ie. Running empty on the flats with the AC on, in 95 deg. air temp.

Everything is new and clean, so I know its getting good air flow. I just need to know if anyone has had a similar experience.

-For what its worth, the temp gauge reads in a very safe/narrow temp range.

[ronniejoe]

The Kennedy clutch will come on much more frequently than the stock unit...but that's what you bought it for. I'm running the exact same set-up (except for 180 stats) and it works great!

[redbird2]

I running the same set up with the Robert Shaw 180 thermostats, when I went from Spokane to home in IL 1900 miles last year it would come on and off driving the montains and hills, the water temp to get to 205 fan kick in and temp would fall right back to 180 this is pulling a 25' double deck liverstock trailer, We had problems going out overheating going over the pass, so I had John overnight me a new fan and clutch out and I installed before the return trip one of the best improvments I did top the truck. I have heard it coming on end off driving pulling a trialer sround home here in IL I kinda like hearing the fan kick on that way I know its working

[john8662]

I have to further agree, the KD clutch was the single most important upgrade I made to the cooling system. The temps were lower and more stable and controllable. I pulled w/o it and the HO cooling system with 180's, bad combination, because the radiator wasn't really hot enough to engage the factory clutch, because of the 180's, until the engine got too warm. Sucks pulling up a regular 5% grade at 45mph only towing an 18' utility trailer with ATV's and dirt bikes stacked all over it, and 7 passengers inside and only having to go slower cause you couldn't keep ECT and EGT confortable...

This is the ONLY aftermarket clutch that does what it's advertised to do, forget the others.

I LOVE the roar at stop lights, as mentioned, cause you know it's working, at least the A/C worked better.

[ronniejoe]

The fan is music to my ears, too, after the overheating problems that I've suffered.

The guys with the Duramaxes have griped so much to GM about fan noise that they've tweaked the clutch to keep it from coming on so much... Now they're complaining about overheating LLY's. Seems they think they can have their cake and eat it too!

[Billy V]

It sounds like everything is ok then. It definitely keeps the temps on the cool side of the gauge and I'm happy with that.

It must have been where I was driving, some hills, and 95 deg. heat with a/c.

[TurboDiverArt]

I don't have the Kennedy clutch but you will definitely hear any clutch kick in more often with the A/C on. This would be even more often with the Kennedy clutch as it activates at a lower temperature. The A/C is exchanging a lot of heat and this heat is increased as it goes through the radiator, this makes the clutch come on more often. When I don't have the A/C on the clutch never comes on unless the temp gauge moves into the 200-range (195 stats). With the A/C on you can hear the clutch engage but the temp gauge can still read below 200. When the A/C is on this is the only time I ever hear the clutch engage when in traffic. I think I have been lucky that my truck has never gotten hot above about 205 when towing and the A/C is on. Believe me, if I ever have trouble I'll be getting the Kennedy clutch!

Now that the intercooler is on, I have not heard the clutch engage (ever in the past 6-weeks) and the temp has never gotten above 200. Even on a long tow up through the northern PA mountains pulling the racecar. EGT

[Kennedy]

Good point Art. There's a lot of skeptics when it comes to intercooling, but the reality is that the intercooler is the single best mod that you can do to a 6.5 TD. Whether it's the performance gains or lower underhood temps. Those who actually make the move are seldom disappointed...

[signgrafix]

has anybody installed an Kennedy clutch and a duramax fan? What are the Pro's and cons?

[TurboDiverArt]

Good point Art. There's a lot of skeptics when it comes to intercooling, but the reality is that the intercooler is the single best mod that you can do to a 6.5 TD. Whether it's the performance gains or lower underhood temps.
Can't say enough about intercooling, the difference is dramatic! I didn't do it for performance but for safety while towing. I didn't add any additional fuel to the engine. I use to have the boost higher to try and lower EGT's. It worked increasing the non-intercooled boost from 8psi to 12psi (sometimes creeping to 14psi) but you needed to be real careful not to blow something up. Adding more boost and not touching the fuel did decrease EGT somewhat but still on long hauls up hills I'd have to get out of it. With the intercooler I was able to decrease my boost to 10-psi, which is a safer limit with stock compression, and the EGT's are absolutely in the basement and water temp is never an issue.

Towing on straights at 70 MPH with 5500lbs behind the Suburban use to pull in the 700-degree post-turbo range before the intercooler install. Now I'm below 450-degrees post turbo with the intercooler.

I recently made my yearly pilgrimage to northern Ohio for a race with the racecar. On previous trips up long 6% grades in the hills of northern PA I

[JohnC]

It might be worth while to try the 180* 'stats. The lower cut-in temp of the fan combined with the high ambient temps and the 195* 'stats may result in an overlap between the cut-in of the fan and the opening of the 'stats. This would cause the fan to run when it really can't do much good.

[TurboDiverArt]

It might be worth while to try the 180* 'stats. The lower cut-in temp of the fan combined with the high ambient temps and the 195* 'stats may result in an overlap between the cut-in of the fan and the opening of the 'stats. This would cause the fan to run when it really can't do much good.
Agreed! But doesn't running the 180 stat's make the engine run less efficiently vs. the 195's? I think it's a pro's and con's things. Having the 195's might make the engine more efficient from an output standpoint but having the clutch kicking more also robs power so you might lose overall efficiency. I think I answered my own question, I hate when that happens....

Art.

[ronniejoe]

I've experimented with both twin 180's and twin 195's. The 180's work better to keep temperatures stable. I'll sacrifice a little efficiency to keep from having to stop with boil over conditions...

[TurboDiverArt]

I've experimented with both twin 180's and twin 195's. The 180's work better to keep temperatures stable. I'll sacrifice a little efficiency to keep from having to stop with boil over conditions...
I think it has to do with how much you're towing. You're towing more than double the weigh I tow. I'm sure if I were towing that much weight (if mine even could) I would be boiling over too and would have to run the 180