D1 Fan clutches

[terryjm1]

I tried to install a new fan clutch, the Hayden 2781, and it doesn’t fit. The heat sink is wider and does not fit inside the fan, Otherwise it would fit.

So, wanting to make some forward progress, I installed a spare used one i found in my parts hoard. I cant recall where it came from. Immediately, I could tell there was a good amount more resistance when cold than the one that was installed. At start up I also could definitely hear more air moving. I couldn’t get too far away as my 12 year old has friends over. So, I drove it at about 20 mph around our very hilly neighborhood and made the 2 mile climb from the entrance off the highway at about 6300 feet to about 8500 feet at our house. There was a 15 degree temperature drop compared to the old fan clutch but I still got up to 220. In my mind, that is too hot and I haven’t put it to the full mountain climb from the desert where the problem was first encountered.

Also, the issue has gotten progressively worse since first encountered.

 

[kris812]

Pretty sure I ordered mine from RockAuto some many years ago when I was having overheating issues rock crawling. It was CHEAP (currently 35-45$ I think I got the URO parts one ERR3443), bolted right up. Only complaint is it spins that fan like a SOB! I mean its noisy and always pushing hard air. It does disengage when very cold though (rare here in AZ so it probably starts WARM). Probably HURT my gas milage a fair bit, but I hold 195-215 in 110F ambient temps.

 

[p m]

Makes me nervous about how hot it was a 3/4 on the dash gauge.

About 235F.

 

[robertf]

Mind sharing which pot luck fan clutch you purchased?

https://www.amazon.com/TUUMOND-Premium-Cooling-DISCOVERY-1994-1999/dp/B08ZSZDSR8/

havent got around to install get. looks identical to one of the junk ones in the pile but has good resistance

 

[terryjm1]

I decided to roll the dice with a URO clutch. Reading reviews it seems the primary complaint is it is locked 90% of time. One of the comments suggested they need time to break in before they loosen up and his works well after breaking in.

I will be finding out soon enough. You all have any thoughts on that?

 

[Rangeroversurfer]

Hello Terry

I purchased this one from Rovers North:

It has held up in Coastal Florida since 2016.

Viscous Fan Clutch For 4.0 Liter V8​

Model #: PLC054​

ProLine Part​

Submit Your Photo

Ready for immediate shipment​

Replaces ERR3443 RNC054


Price: $126.50

 

[terryjm1]

The URO fan clutch arrived today. I drove about 30 miles and the hottest it got was 186 and that was during a 20 mile uphill run. It was a very cool day on the mountain, under 70 degrees after a rain storm. I won’t feel totally confident until I take it into the desert and back up the mountain but it is clearly a lot better and think this confirms I don’t need a radiator.

It does sound like a helicopter but I could tell it was disengaging when it got below 180. Some of the reviews said it needed a few weeks to fully break in. We will see.

 

[kris812]

If anything, my URO fan clutch has gotten louder with age. I sat idling for over an hour in 110f Ambiant temperatures watching my gauge. Seen as high as 222f on coolant with AC on. Dropped down once I started moving again.

To add to this FAN information: The front AC fan motors can have the motors replaced if you order a fan motor for a "96 toyota corolla"; bolts right on, splice wires in! They also seem to BLOW a LOT more air than the stock fan motors, but then again my old ones barely worked before they quit. Only downside is they don't have the same water drain tube on them, which probably caused them to fail anyhow.

 

[terryjm1]

It has been puzzling as the overheating was worse when going uphill (expected) but i was going fast enough (45-50) to move plenty of air but it was still getting up to the 230s which forced me to stop and let it cool off. I have put another 15 ish miles on it today. It doesn’t get above 186 now but mostly stays right under 180. It idles for extended periods and stays right around and under 180 as well. I’m heading down to the desert this evening and the trip back up will be a good test to know for certain if the fan clutch solved the problem.

Looking closely at one of the old fan clutches the spring on the front of one of them was completely tightened down.

 

[Greg_M]

To add to this FAN information: The front AC fan motors can have the motors replaced if you order a fan motor for a "96 toyota corolla"; bolts right on, splice wires in!

Corolla part PM9115

 

[terryjm1]

Well, on the climb up from the desert today at 95 degrees with the air on it only got up to 195. It still sounds like helicopter but it isn’t overheating, Seems the fan clutch was the problem.