added UD pulley's, need to change anything?

[Sburn]

Originally Posted by JackandJanet

Or, if you had access to a 2008+ truck, you could try spinning the fan by hand with the engine stopped. If you feel drag, it's going to be there anytime the engine is turning.

- Jack

So, you're suggesting I might hook a fish scale up to the fan with the engine stopped and measure the drag as torque, right? That could be good to know. Not sure about 2008+, but my 2007 does have some drag when stopped, so whatever scheme the clutch is, it's not perfect.

[Jackpine]

Originally Posted by Sburn

So, you're suggesting I might hook a fish scale up to the fan with the engine stopped and measure the drag as torque, right? That could be good to know. Not sure about 2008+, but my 2007 does have some drag when stopped, so whatever scheme the clutch is, it's not perfect.

I thought you said the change was in the 2008 MY. My 2005 certainly has viscous drag when I attempt to spin it by hand with the engine stopped. I haven't actually tried this, but as I understand it, the drag should be greater if the engine is hot. (I'll have to give it a try). In my engine, the fan ALWAYS turns, but, it is supposed to turn faster (closer to engine speed) with the engine hot. (I know you know this, I'm just adding it for anybody who may not understand how a viscous clutch works).

I doubt you could measure it with a fish scale though on a stopped engine. You'd need to catch the fan to a scale mounted on a rafter or something and measure the force on the stalled fan with the engine running. Then, you could calculate the torque/hp loss from this force and the distance you had the "hook" from the hub. It's not something I'd like to try, since it sounds a bit dangerous.

But, if there is NO resistance in the 2008+ line, then that is a whole different clutch! And, you should be able to compare the relative resistances in different MY trucks by feel.

- Jack

[Sburn]

Originally Posted by JackandJanet

I thought you said the change was in the 2008 MY.

2006 or 2007, AFAIK. PCM-controlled fans have a harness with connector a 5 wires that sit between the water pump pulley and the fan hub.

My 2005 certainly has viscous drag when I attempt to spin it by hand with the engine stopped. I haven't actually tried this, but as I understand it, the drag should be greater if the engine is hot.

If harder to turn when hot and no wiring, then that sound like your 2005 has thermo controlled clutch.

I doubt you could measure it with a fish scale though on a stopped engine. You'd need to catch the fan to a scale mounted on a rafter or something and measure the force on the stalled fan with the engine running. Then, you could calculate the torque/hp loss from this force and the distance you had the "hook" from the hub. It's not something I'd like to try, since it sounds a bit dangerous.

Right, not a good idea to do it that way.

[88Racing]

Here is some more reading on fans:http://dygytalworld.ehost-services13...read.php?t=467

Lars

[Jackpine]

Of course I'd completely forgotten that thread, Lars. AgentOrange really improved HIS mileage with the e-fan, didn't he? Same truck as mine too.

Looks like, according to my Haynes manual, that your 2006 had the viscous clutch fan too. Didn't you put in e-fans Lars? I know you replaced the pulleys. How has all this effected your mileage?

I guess the next time I'm at the dealership, I should go try to move a fan by hand to compare the resistance in the newer setup with mine. There's no doubt at all that there's significant, CONSTANT drag on the engine with my fan, regardless of the need for cooling.

- Jack

[th3godf4th3r]

about to add the e-fans. need to do anything? just up the idle speed?


for anyone that has them, what did you set the temps at? i live in seattle so its never super hot and never super cold

[Jackpine]

Originally Posted by th3godf4th3r

about to add the e-fans. need to do anything? just up the idle speed?


for anyone that has them, what did you set the temps at? i live in seattle so its never super hot and never super cold

I don't think the ambient temperature is of concern to you. What does matter is the engine temperature. You'd like it to be in the 200 degree range, for best performance and fuel economy.

I don't have them, but I think I'd start cooling things off if I saw 210 degrees.

And of course, you do not want them on at all if the engine is cold.

- Jack

[88Racing]

Originally Posted by JackandJanet

Of course I'd completely forgotten that thread, Lars. AgentOrange really improved HIS mileage with the e-fan, didn't he? Same truck as mine too.

Looks like, according to my Haynes manual, that your 2006 had the viscous clutch fan too. Didn't you put in e-fans Lars? I know you replaced the pulleys. How has all this effected your mileage?

I guess the next time I'm at the dealership, I should go try to move a fan by hand to compare the resistance in the newer setup with mine. There's no doubt at all that there's significant, CONSTANT drag on the engine with my fan, regardless of the need for cooling.

- Jack

No efans yet.
Got .5 mpg better and more pep in stock.
Just a note on troyer's controller: Use a SPAL one instead.
Detailed instructions come with the kit.
Use a ir point and shoot temp gauge on upper radiator hose to determine on temp.

Lars

[th3godf4th3r]

ok so i installed them today and got them running.

heres a couple questions

i set the fan to come on at about 195, should i set it higher? lower?

to set the second fan at 205 is it easiest to drive until i get to that temperature and then run and turn it on? i had it sitting running in the driveway for a good 15 min and never got above 196