Electric/dmax Fan Upgrade

[njdevi11]

I looked into the dmax fan upgrade kit and i think it might just be easier and more powerful to put an electric fan on my setup, The fan pulls 2200cfm and comes with a shroud made for my radiator. I have two options for fan on and off temp. One is on at 185* and off at 170* and the other is on at 200* and off at 180*, Will the lower temperature keep the fan on too long? I know overheating is a problem with these engines but diesels need the heat to keep running.

What is the stock fan rated for in cfm, and what are the specs on the fan clutch?

I'm also a little worried about trashing the electric fan with mud and water. But at $60 a pop if i get over a year of service out of the fan i can chalk that up to maintenance.

If i decide not to go with the electric i will probably get the dmax style How do you tell when your fan clutch is going bad? will it become to tight or too loose?

[sixnickel]

I know cooling is a big thing with 6.5s but onless you are towing something heavy with that Jeep I would'nt worry much about getting it hot. Whats that thing weigth ?? That thing will be so over powered the engine will never work hard enough to get hot! My thoughts!

[Husker 6.5]

I looked into the dmax fan upgrade kit and i think it might just be easier and more powerful to put an electric fan on my setup, The fan pulls 2200cfm and comes with a shroud made for my radiator. I have two options for fan on and off temp. One is on at 185* and off at 170* and the other is on at 200* and off at 180*, Will the lower temperature keep the fan on too long? I know overheating is a problem with these engines but diesels need the heat to keep running.

What is the stock fan rated for in cfm, and what are the specs on the fan clutch?

I'm also a little worried about trashing the electric fan with mud and water. But at $60 a pop if i get over a year of service out of the fan i can chalk that up to maintenance.

If i decide not to go with the electric i will probably get the dmax style fan (just the fan) from autozone for $50. How do you tell when your fan clutch is going bad? will it become to tight or too loose?

Use a 180* thermostat in the engine to keep it running cool. Use the higher setting, otherwise the fan off setpoint and engine thermostat will be in conflict with each other. If it is an automotive electric fan, your OK, they're watertight. 2200 cfm is plenty.

YOU CAN NOT USE A D-MAX FAN! The D-max and 6.5 fans are serpentine belt CCW rotation fans. Your 6.2 is a V-belt CW rotation fan. Stay with your fan with a clutch, or go with a Flex-i-lite severe duty "fly-swatter" and eliminate the clutch for more cooling, unless you want to convert you 6.2 over to a serpentine system, a royal PIA involving some fabrication and $$$$.

Cold and with the engine off, your fan should rotate freely. If it is stiff, jerky, or locked-up, your fan clutch is shot.

[njdevi11]

Well, my fan is tight but it spins freely. It's not jerkey but kinda feels like a shock moves. Slow steady and smooth. If I give it a good push it wont keep spinning though.

Why cant i mount the Dmax fan backwards if its reverse rotation?

The fan kit i'm looking at is summit part SUM-381008 (you can go to their website and check it out). Its comes with a shroud matched for may radiator (since its a summit aluminum radiator) and its only $170, less then the cost of the dmax fan stuff. All i need to add is a temperature switch for $20 and a relay. I really want to make sure i have this 6.2 around for a long time. But I know in a diesel you can overkill cooling and end up never getting the temperature hot enough to get good combustion. I probably wont be towing but i will be pushing 36-40" tires.

I dont know what the weight will be when im done but I will definitely find a scale. Just a rough estimate.
1000 6.2 + all accessories
500 Trans+TCase
250 Frame
250 Body
500 Axles
500 Tires+wheels
500 everything else i forgot about

Guess were looking at a dry weight of around 3500lbs Its a tinker toy :D .

[Husker 6.5]

Well, my fan is tight but it spins freely. It's not jerkey but kinda feels like a shock moves. Slow steady and smooth. If I give it a good push it wont keep spinning though.

Why cant i mount the Dmax fan backwards if its reverse rotation?

The fan kit i'm looking at is summit part SUM-381008 (you can go to their website and check it out). Its comes with a shroud matched for may radiator (since its a summit aluminum radiator) and its only $170, less then the cost of the dmax fan stuff. All i need to add is a temperature switch for $20 and a relay. I really want to make sure i have this 6.2 around for a long time. But I know in a diesel you can overkill cooling and end up never getting the temperature hot enough to get good combustion. I probably wont be towing but i will be pushing 36-40" tires.

I dont know what the weight will be when im done but I will definitely find a scale. Just a rough estimate.
1000 6.2 + all accessories
500 Trans+TCase
250 Frame
250 Body
500 Axles
500 Tires+wheels
500 everything else i forgot about

Guess were looking at a dry weight of around 3500lbs Its a tinker toy :D .

Your fan clutch is OK. What you're feeling is the resistance of the viscous silicone inside the clutch, it won't "free spin" because of the silicone fluid (but because of airflow through the radiator past the fan at road speed while the clutch is disengaged, the blade will freewheel at a speed different than engine RPM) but the important thing is that you don't feel a mechanical "catching" or it's locked up completely.

Because if you turn the fan around, the pitch of the blades will still be CCW! Think in terms of a common right-hand thread bolt. When you tighten the bolt holding the nut, you turn "righty-tighty" (CW). Now look at the nut end, and hold the bolt head. You still turn CW to tighten. Same thing with blade pitch, or water/hydraulic pump vanes, or windmills, they only work one way.

I'm very familiar with Summit's catalog. A 2200 CFM fan will move plenty of air. You will be fine with a 180* thermostat, it will ensure that you don't toast your heads, yet prevent you from running too cold (165* stat) for optimal thermal efficiency. Sixnickel is right, you'll be putting no strain on that motor in your Jeep, even with your jumbo tires!

My truck weighs 7100 empty, and over 9000 when I'm loaded, and that's not even pulling a trailer, and I ran with a 180* in a stock cooling system. I am upgrading to the 97 system because of my performance upgrades, and 105*+ summer days, but will add the D-Max fan only if I need it.