@Richard Gallant understood. All good points. I will read the article you provided. I didn't take much to talk me into it...

I understand the implications of overheating an all aluminum motor, in particular one with press fit steel liners. Agreed that having extra cooling capacity is a good thing and an extra safety measure. I guess for less money you might as well upgrade huh? Thanks for talking me into it.

My concern around robbing power is more the added stress on the motor due to more resistance from the clutch. I assume that is also fairly insignificant? Electric cooling fans would be awesome if there was an easy mod for that. I come from the motorsports world where turn off your electric cooling fan on the track, and turn it on when you pull in pit lane. I have read about people doing it, but not willing to take that leap myself haha.

 

Can't imagine that the fan on the front of the engine will be significant compared to the transmission that's hooked up to the back. Some folks have done electric fan conversions, as they can be helpful for wading situations, but that's a bit more of a project (having to fabricate mounts and then wire it to turn on based on temp/speed).

 

Go with the inline thermostat if you want cooler temps

I think I remember best 4x4 saying the Hayden and fan combo do work harder and does take power away from motor
probably similar to ac being on

 

@redwhitekat Ive read some about the in-line mod. My truck has a LR 180 thermo in it now, I might consider the inline mod down the road. I’m happy with my temps, and they will certainly improve slightly with a working fan clutch. Once moving at any speed temps are never over 195. Maybe on a really steep incline with a heavy load.

idle is where the temps can creep towards 200 and the fan clutch is not going its job.

I thought the water pump had been done recently on this truck. I reached out the PO and turns out the water pump was replaced about a year ago.

It’s not leaking so I’ll leave it for now and just do the fan clutch.

I did decide to go with the Hayden severe duty fan clutch.Thanks for The input on that everyone.

 

Try the newspaper test on a hot day with a hot engine. You shouldn't be able to get the fan to a stop (there are videos on youtube). I tried and could get the fan to a stop easily, a sign that the clutch didn't work. The new fan assy made a difference, especially at idle. I tested the old fan assy, heated up the bimetal spring with a hot air gun and it turned the pin as it was supposed to, but there was no difference in resistance compared to cold. The clutch was definitely broken.

 

let us know your reviews on the Hayden fan clutch once you get it in

 

@Discorama Newspaper test I assume would be sticking a rolled up newspaper into the spin going fan to try and stop it? Simple enough, I’ll give it a shot.

I’ll report back on the Hayden fan clutch. I ordered a water pump as well. I will probably hold on to it as a spare for now.

 

I got an OEM fan you can have if you pay shipping. Just let me know.

 

Yep another clutch fan gone bad.....Your "at idle" slow temp climb is exactly a faulty clutch fan, it's not moving enough air to keep cool. If the clutch fan doesn't fix the situation though, put a new radiator in it.

 

Thanks for the offer @cvhyatt , but I went with the Hayden severe duty.

@Motorhead1 agreed. I replaced the Auxillary/ a/c fan last week. My radiator is in good, not great shape. Lots of bent fins, and the remnants of bird who's life was cut short... I plucked out all of the debris with a radiator comb.

I do have a very very small coolant leak, and have not been able to find it actively leaking. Coolant level holds steady for days, and then after driving the truck for quite a while it will leak after being parked for an hour or two. It never leaks more than a few mm of coolant level out of the reservoir. The leak is right under the driver's side of the radiator. I am going to borrow an IR gun soon (they're at every restaurant now to take your temperature... thanks corona...) and measure the temp of the radiator top to bottom. I would be a little surprised if it is clogged with as good as my coolant temps are when there is any RPM at all. If I am sitting at idle and the temp goes up from 194 to 195 or 197 I can bring up the revs a little, and it drops back down.

It's completely possible it's one of the lower radiator hoses - the PO of the truck pulled the motor and did HG's and motor mounts before I bought it. So everything has been recently reassembled.