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2nd Gen Non-Engine/Transmission radiator flex fan

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Is anyone running a flex fan on their 12V dodges? I'm fairly certain the clutch is not working because I can't hear the fan engaging and she gets hot sitting in traffic. I would prefer a flex fan set and eliminate the clutch if this is something that is available and other have done it... . with success.



Thanks
 
I do not like flex fans at all. They have a nasty tendency to loosen and come apart at the rivets and they always rob horsepower and fuel economy. Metal fatigue also sets in eventually. There are good reasons you do not find them on heavy duty equipment. I have never even seen a factory-installed one on any vehicle, and those pennypinchers would do it in a heartbeat if it worked at all.

You need to just replace your fan clutch, imo.
 
Flex Fans

I too would avoid the flex fan. A few years ago, I spent many thousands building an old Datsun 240Z motor to about 400 ponies. I bought a high dollar flex fan. On initial startup, the blades flexed backward and cut a nice circle in the new custom radiator! Of course the company offered a new fan, but I was screwed on the radiator. If you want to get rid of the stock setup, go electric. You can get a twin setup that gives you a backup if one fails. They can be pricey, but the old cliche still fits - "you get what you pay for. " Going cheap and easy can cost more in the long run than doing it right the first time.



Dave
 
Thanks for the inputs guys. Who makes the electric units... and do they offer superior cooling?



I didn't see the electric unit on Genos.
 
Truthfully, Texis, I don't think you can beat the stock setup for cooling or reliability. If anything, I have trouble during chilly weather staying at operating temperature and have to block the radiator in really cold weather. During summer, my fan clutch seldom even kicks in.

It may have been awhile since yours worked, so you might have forgotten how well it does work. Overheating is not a common topic even here on TDR.
 
I have had the truck a long time without over heat issues. But somethings up? installed a new thermostat last summer, radiator has never been boiled... but appears clean (no visable built up on the core ports)



I only noticed last summer that I never hear the fan "kicking in" and a couple of days ago she got up between 200-210 in a Houston traffic jam ( 1 hour, 80 degrees, AC on high) The truck has never been above 190 (thermo setting)



Is Dodge the only source for another fan clutch?



Thanks
 
The stock fan is engineered to move a lot of air if needed. In full lockup it can use around 6 horsepower. That is a lot of air. A flex fan isn't likely to move as much. An electric fan would need to pull an awful amount of amps at 12 volts to move as much. It would be in the range of 4500 watts. That would mean around 375 amps.



Your best bet would be to replace the fan clutch.
 
The stock fan and clutch are designed to move enough air to cool an engine moving GCWR mass in 'all' ambient conditions.

Flex-a-lite clearly state that their dual electric fan is good only up to a certain weight (maybe 15000#; I don't remember off-hand; check their web site).

If you only tow little trailers, the electric fans will be fine.

If you tow heavy (5er or loaded dump trailer, for example), stick with the stock fan and clutch; the engine will generate a lot of heat that must be removed.

NAPA and other stores will have the fan clutch.
 
I will have to agree with the argument on getting the flex a lite fans. I actually ran them on my 24v. I pulled over 15k with out a problem. I also didn't have a problem with getting heat in the engine for the same reason ( I put a toggle switch, so I could manually turn them on and leave them on). My problem came 20k miles after putting them on, rivots blew. Repair or replace, it was going to cost the same, so I went back to stock setup.
 
When is the last time you had your radiator off? Every time I have had a heating problem it was the bug and dirt in the radiator. It wouldnt look all that bad but would be heavy to lift out. It is not a real hard thing to do. This is just another thing it could be.
 
I have never had the radiator out. Looks clean, I suppose that I assumed it was because I see nothing bad? Will they glog up with road dust to the point of causing heat issues?... makes perfect sense.



Could be an issue of glogged radiator + clutch not working. 2 things wrong at the same time makes bad stuff happen faster, and is harder to track down.



Assuming the radiator is not internally corroded and not leaking, would there be a need to replace it... because it has 336K on it? Or just clean it?
 
Good point, HCannon! If you spend any time at all around livestock, there's a good chance your cooling fins have more hay and straw and crud in them than you think. You can't see it, but a careful powerwashing might prove it.

My K30 came from a Texas ranch. the radiator looked great inside and out, but the truck ran hot. When I took it off and powerwashed it, I couldn't believe how much crud those fins can pack in there! problem solved!

But if your clutch fan is out, replace it first or at the same time. Electric auxiliary fans are OK, but you should keep your stock fan and consider pusher electrics. Just stay away from flex fans.
 
I don't know about ya'lls fan clutch, but mine doesn't lock and unlock like a compressor clutch. Mine is a viscous type design that you will not hear an engagement. I agree with the others that advise against the flex fan. The stock clutch is simple, reliable, cheap, and maintainance free. It also works. An electric pusher fan may not be a bad Idea for when your in stop and go traffic. Just my $. 02. Good luck.
 
I don't know about ya'lls fan clutch, but mine doesn't lock and unlock like a compressor clutch. Mine is a viscous type design that you will not hear an engagement.



I think they just meant you can hear the fan roar when the clutch is engaged, vs. it being much quieter when disengaged. They are all viscous.
 
That's correct. When it is working properly you can hear the fan roaring periodically as the temp rises. Problem is that I haven't heard it in 2 years! In fact I had forgotten that it is suppose roar when it needs more air.



When the engine is cold the fan will turn by hand, but has some resistance and will not spin freely. The book states it should "turn freely" when the engine is cold?... and have some resistance when the engine is hot.



How does this compare with some of you guys fan clutch?
 
One easy check: if the belt never squeaks when you shut the engine off when the air and engine are hot, the clutch is probably done for.
 
I don't have an EGT guage.



I haven't heard the "chirp" in a long time, never gave that any thought. I guess I forgot that they are supposed to chirp!
 
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