Thermostatic Fan Clutch on 230?

[ashyers]

I was wondering if anyone has retrofit a thermostatic fan clutch on a 230. The reason I ask is that the engine seems to be cold blooded due to the mass of cast iron and the huge volume of coolant. My thinking was I could reduce the warm up time and on cold days pick up 1/4 hp!

[F18hornetm]

Did you have any plans on how to use that extra 1/4hp ????

[w30bob]

Hi Ashyers,

Just thinking about this a bit......the radiator is out of the cooling circuit during warm-up, thanks to the thermostat being closed, so why would the warm up time be less with a thermostatic fan clutch? A couple of things to consider when using one......there's nothing simpler than the stock direct drive fan....it really can't fail.....and for a military vehicle I'd think that's important. Also, the fan clutch and water pump share a common shaft, so if either fails it will ruin the other. Meaning if the clutch bearing starts going south it will cause the fan to wobble, and that will tear up the water pump bearing. The opposite is also true. For this reason I believe you're supposed to replace both the pump and the fan if one of them goes bad. So in my eyes (which aren't the best these days) you're going to make a pretty bullet-proof system a little less so. The M37 radiator is HUGE compared to what's used in civilian 6 cylinder applications, and they did that for a reason. Plenty of capacity for operation in hot conditions and as simple as can be........which makes it reliable as can be.

That being said, you'd probably free up significantly more than 1/4 hp with the thermostatic fan clutch. That assumes you can find one that fits and puts the fan at the proper distance from the radiator. Certainly an interesting thought.....and the 230 might not sound like it's gonna puke it's brains out at 50 mph with such a fan.

If you do it make sure to post some pics!!

regards,
bob

[ZGjethro]

I have also wondered about putting an electric fan on my truck. I have a few saved from online searches, but I have not acted on them. I have not wanted to deal with radiator shrouds and fan mounting when my brakes are as crappy as they are now. If I add a power steering pump, I might look into an electric fan. Are there any issues with the electrical charging system? Will the system charge the truck and run a fan? I am assuming it will

[ashyers]

Bob,
You bring up some valid points, but I don't think I'll be using the truck like it may have been used in the military. I figure a thermostatic clutch similar to what I have on a few of my vehicles w/ AC works great, there's no fan noise or drag when not needed and when it is necessary it's engaged. I have a feeling that the factory fan is overkill for my use of the truck, and a clutch would allow the best of both worlds, with a minimal sacrifice of reliability. I would prefer a clutch fan to electric, but that will depend on what may work on the factory bolt circle. I'm not sure if there's an electric fan available for 24v????

Anybody know the bolt circle of the factory fan and the dia. of the water pump snout?

Andy

[ZGjethro]

If your goal is to free up some power, I don't see how a clutched fan would help. You motor is probably working the hardest on a big hill, and that is when you need the power and are overheating. An electric fan would meet your goals better I'd think http://www.okoffroad.com/stuff-fan-24.htm.
https://www.flex-a-lite.com/electric-fa ... -fans.html

[ashyers]

A thermostatic clutch fan is a bit different than a standard clutch fan. It only engages completely at around 200F. Essentially it works like an electric fan w/ thermostatic control, w/o all the electronics.

[Monkey Man]

I have tried this, I got a fan assembly off a Toyota 18R engine, we made an adapter boss and fitted it being careful to make sure the shaft went all the way into the fan boss to allow thermal transfer, in short, it didn't work as there was insufficient heat transfer on the water pump shaft to actuate it and even after some fiddling with the thermo spring it was marginally better but still not good enough, you may have better luck with a different engine's clutch fan assembly.....
Do yourself a favour, if you insist on giving the metal fan the flick, fit a Davies Craig or similar electric fan with thermo switch and you will be set, you gain the extra HP and your fan only runs as needed, at 30 MPH or higher it basically never runs unless climbing a big hill under load and even then it is very intermittent.

MM

[ZGjethro]

A thermostatic clutch fan is a bit different than a standard clutch fan. It only engages completely at around 200F. Essentially it works like an electric fan w/ thermostatic control, w/o all the electronics.

Wouldn't it have a parasitic energy draw when fully engaged though?

[ashyers]

Yes, when engaged, I just don't see it being engaged frequently with what would be regular use for me.

[w30bob]

Hi Guys,

My '88 Chevy dually came from the factory with both a Thermo Fan Clutch on the fan and an electric fan in front of the radiator for when things got really hairy. When the Thermo clutch kicks in you know it......things get loud quickly. Over time the silicon leaked out of the Thermo fan and I never noticed..........that is until If found my electric fan running when I shut the engine off. Then one day while I was pulling a trailer of hay I noticed the temp gauge crept a little past where it normally sits. Checked the electric fan and the relay went south.

So both the Thermo and the electric work.........no doubt about it. But they also wear out and/or fail over time. Having just one will leave you calling for a tow at some point....having both can avoid that if you pay attention. But nothing is more reliable than a fixed fan.

Not saying you shouldn't do it, it just doesn't make the truck more reliable (in my mind). Did anyone give you the bolt pattern on the pump? If not let me know and I can measure for you.

regards,
bob

[ashyers]

Bob,
No luck on the bolt circle yet. I need the BC and the water pumps snout diameter.

We've been busy working on getting the truck road worthy so we have not had time to pull the fan and look at any "modifications". I am hopeful that we will have a running/driving/tagged truck in 2 weeks . I would say confident, but I'm waiting on a few bits that are already over due... fingers are crossed!

Andy