New upgrade, that possibly nobody ever wanted!

So a few days ago, I was listening to the cooling fan on my dauntless just huffing away (I'm assuming it's the original, it's an Asymmetrical 4-blade steel fan, it was on there when I bought it anyway) And happened to be looking under the hood.

Now, I was already running a 1" spacer between the pulley and the fan, for other reasons, and it got me to thinking....

I grabbed my tape measure, and had a look, and at least on *my* CJ5, where the factory planted the dauntless, and where they planted the radiator, I've got about 3 1/2" inches between the two.

So I think to myself "Somebody out there has to make a fan clutch that fits in that envelope, right?"

Grab a few measurements, and find that nobody *really* lists out fan clutches by dimension, *but* Hayden has a nice catalog that lists all their fan clutches and applications, and 4-seasons actually publishes all their dimensions (heck, I'm pretty sure they're the same company.) So I start going through the list, and plugging numbers into 4-Season's interchange, and low and behold, I came up with something that should work.

Thus:


Clutched Fan on a stock dauntless! Now, I don't know if anybody ever *wanted* to do this or not, but it certainly can't hurt. Turning that steel fan constantly does actually use horsepower, no matter how little, and it makes things warm up a bit slower, as it's *always* blowing. And *wow* is the fan noise less with this six blade.

Here's a few more pictures of it going together:

The original application for this fan clutch actually uses two differing pilot diameters, I don't actually know the metric measurements, but they're roughly 3/4" or 5/8", and if you buy this clutch new, they include a handy little bronze bushing to fit 5/8" pilot applications:






Now, I'm sure you're all sitting there, just waiting to order these parts. So, what do they come off of?

Volvo 740...

No foolin.

The Fan Clutch is a Hayden 2558, which bolts right up to the water pump, without modification, and the use of the bronze bushing. You just need 4) 5/16"x3/4" Fine Thread bolts to put it on (which *can* be a little tricky to get in there, I put them in the slots of the flange, then tossed a rubber band around them to hold them in place while i put it on the pilot. I'll probably switch it to studs when I change the water pump at some point in the future)

You'll also need 4) M6-1.0 Nuts to attach the fan to the clutch, as they're not included with the new clutch. (I just grabbed them off of the rig I got my fan off of...)

And the fan is also off of a 740 non-turbo. Which at least around here, are fairly plentiful in the boneyards, and at least according to the hayden website, and rock auto, basically All the Rear Wheel Drive volvos (240/740/760/960) starting in 1975, up till whenever used this same fan clutch and fan. I went for a new clutch, because I didn't know if the stock one was slotted, or drilled for the bolts (Turns out it was slotted).

The fan is basically the same overall diameter as the stock one I took off (Right around 15")

And what seems to be a pretty good bonus? I don't have it on there yet, because I haven't figured out mounting yet, but it looks like the fan shroud off of that same 740 will fit just right on a dauntless radiator, they're basically the same width.

Now, things will work out better if I drop my radiator a couple inches, but I can't do that until I do my steering conversion, so I *might* not mess with the fan shroud until I do that. But honestly, it was basically the same issue with the stock fan, the blades protrude down under the bottom of the core by 1/2" or so.

 

I built a homemade shroud for my 70 v6 and yes, the fan hangs under the radiator.
Good info, thanks for sharing!

 

Good on you for doing your homework! I was wondering how you were going to get around the centering post differences... the bronze bushing is awesome.

FWIW, for anyone else looking to do this, the fan models that aren't slotted, like mine ('87 740GLE non-turbo), the bolt pattern is/could be much bigger than the Dauntless. Slotted mount is the key.

 

Yeah, if you buy a fresh one, they're all slotted mounts, at least the ones I could find. You could run into drilled ones if you're pulling them out of the boneyard.

 

Good to know!

 

Good information. Thanks for sharing.

 

I have wanted to do this ever since I took out my radiator out on a creek crossing. I'll have to see if this will work for me.
thanks

 

Wow! Great post! Thanks for sharing, nicely detailed info with pic's

 

Heh. I picked up mine at autozone, it was in stock, might be worth checking your flaps.

 

Oh, I almost forgot... If you get a *new* clutch, you'll need to source some M6-1.0 nuts for fastening the fan, as they're not included with a new clutch. I just grabbed the ones off of the rig I got the fan off of in the boneyard.....

 

Here's a few other options for clutches, I just can't verify that they'll work. Honestly, the bigger issue is finding the fan to fit them, than the clutches themselves. These three will fit the same bolt circle for the fan, as the volvo.

2554 2.4 Depth, 4.79 Bolt Circle (88-95 4 Runner, 4 Cyl)
2558 2.3 Depth, 4.79 Bolt Circle (Volvo, 240)
2565 2.32 Depth, 4.79 Bolt Circle (89 Mitsu starion)

And this one, if you want to move your rad forward a bit, is probably going to be the best, as 3 1/4" bolt circle is what has the best availability for aftermarket fans. It's just too tight for my application

2665 2.92 Depth, 3.25" Blt Circle (96 Jag XJ)

 

I'm running a 7 blade Waggy set up(because I had it lying around)and it works great. I am using a rad from a 84 CJ that had a 258 so it does fit it nicely with my homemade shroud.

 

2.3-ish inches from the pulley surface to the furthest point out. I *think* I've got a six blade fan, but honestly, I didn't count, I'd have to go look, it'll have to wait till after I get home from work tomorrow. Dead tired right now.

On this setup, the fan is actually recessed on the clutch, so the clutch is actually the furthest point out.

 

Just verified, it is a seven blade fan that I've got. Not sure what year I got it off of, but it was a 740 Sedan