504 Fan Override switch

Tom_95

Tom_95

Member
Fellow Frogger
Joined
Jul 4, 2011
Messages
293
Location
Sunshine Coast, Queensland
Hi all,

After finally getting around to making the viscous fan work properly in my 504, I'm finding it still gets a little too warm for my liking in certain situations (heavy stop/start traffic etc).

For piece of mind, I'm thinking of installing an on/off switch in addition to the fitting in the bottom of the radiator. The idea being that I'll leave it in "auto-fan" mode 90% of the time, and then force it to engage using a switch under the dash when needed.

So, I'm assuming it's just a matter of running wires from either side of the temp sender to a switch inside the cabin?

Additionally, does anyone have any other solutions/thoughts on this?

P.S - The cooling system itself is healthy. With the thermo-switch shorted, the temp gauge doesn't go above half-way in any circumstance.
 
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Doesn't a viscous fan work off temperature, not electrically? Or do you mean the A/C fan is to be switched manually?
 
Stuey said:
Doesn't a viscous fan work off temperature, not electrically? Or do you mean the A/C fan is to be switched manually?
Click to expand...

I believe the op is confusing a viscous fan coupling with the magnetic clutch that is used in a 504. :wink2:
 
I would adjust it up and lock it up as well. A bit more noise and a little less power but more peace of mind. Always did with my 504s.
 
Tom_95 said:
Hi all,

After finally getting around to making the viscous fan work properly in my 504, I'm finding it still gets a little too warm for my liking in certain situations (heavy stop/start traffic etc).

For piece of mind, I'm thinking of installing an on/off switch in addition to the fitting in the bottom of the radiator. The idea being that I'll leave it in "auto-fan" mode 90% of the time, and then force it to engage using a switch under the dash when needed.

So, I'm assuming it's just a matter of running wires from either side of the temp sender to a switch inside the cabin?

Additionally, does anyone have any other solutions/thoughts on this?

P.S - The cooling system itself is healthy. With the thermo-switch shorted, the temp gauge doesn't go above half-day in any circumstance.
Click to expand...

I have had mine wired as you have suggested for most of my Ti's life. I also ran a wire across to the unused large red light socket above the speedo with a warning light (The warning light illuminates when you turn the fan on and/or when the fan turns on via the sensor in the radiator). I stuck the switch next to the wipers switch.

The fan cuts in at 82C and cuts out at 72C, it takes a while for the temperature to get back to 72C, so like you suggest turning the fan on in heavy traffic saves it cutting in in the first place.:headbang:

Like has been stated many times, the fan takes 12bhp off the Ti motor, so why would you lock the fan in??? :confused: (Unless the solenoid clutch can not be made to work).
 
Tom
I think what you intended to do and the way you suggested to do it is fine. I certainly have done it on my 504s.
I do think that the 504 does seem to take a bit too long for the fan to cut in for my liking.
Anyone climbing a steep hill and then flick the manual override on the fan, it is like throwing out an anchor.
For this reason, no way would I lock the fan permanently if the system is working properly.
Bob
 
I have swapped the radiator sensor to a 92C in 82C out one from a Reno 16Ts. Been there for year too. The fan cuts in just as the temp gauge reaches the very top of Normal. The temp has never gone higher than this ever and I am in Sydney.
 
^ That's a good idea, BigRR.

But Tom, those fan blades are not getting any younger, and when they get old, they get stiff and break off, thereby ruining your radiator.
Also due to age, the electromagnetic hub shorts out internally from heat and vibration, and stops working.


If it was me, I'd be installing an electric fan....it is a popular conversion, and you will forestall those two problems.....plus your original one .You can do it for less than $ 100, or if you are into saving money, you could get a good one from the wreckers. It would take a few measurements of the existing space though. And you may have to make up brackets, but no big deal, really.

Sucking is more efficient than blowing, so mount the fan on the engine side of the radiator. And I think that to create space, you chop off the end of shaft coming out of the water pump, on which the electromagnetic hub is mounted.

I have never done it, but have seen the end result, and people have been happy.
 
Yes, those old fan blades do get brittle and the magnetic hubs do fail. Particularly if you live in Qld you need something reliable and something you dont have to remember to engage. Go for the electric fan option as per Beanos post. BTW, a loss of 12 Hp sounds a bit high. Seem to recall a figure of 4 hp. Anyone? Regardless, think I'd rather a bit less horsepower than a cooked engine.
 
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Never had problems with mine, only 45 years old yet. (Although I had to replace the carbon brush a few years ago). :blackeye:

Drove 220km today still all works. :)
 
I'm surprised that nobody who has done the conversion has seen this thread and commented.

My local Pug mechanic years ago did in fact tell me that theoretically, if I locked up the fan hub on my 505 SR, it would lose 10 horsepower.
But I locked it up anyway as I really wanted to get rid of potential weak links like that.
 
I would not have thought that a light nylon 504 fan blade could ruin a radiator.

Maybe the blades fly off faster if the clutch has been locked up! :evil:
 
^ Heh...

After all, 504 radiators are only thin copper. We had a member here named Mud (because that as his number plate) who bought a REALLY original and well looked-after 504 from a friend of mine.
Mud fanged cars around a bit, and he caused the fan to disintegrate, then fitted a Holden radiator, and did a thread here about that.
 
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These fans sometimes age well and remain flexible but sometimes they become as brittle as anything. Disintegrating blades can and do hit the radiator puncturing it.
 
Still find it hard to believe.

Any 1st hand experience with 504 nylon fan blades disintegrating and puncturing the radiator?
 
The only time I have seen fan blades shear off is due to idiot 4wdriver's plowing through water at great speeds.

My 504 fan is still in good condition and is still quite flexible with no signs of the plastic breaking down.

My fan is locked on. I do run air con with an electric fan in front of the condenser. The electric fan comes on with the compressor.

I also have a Commodore (VL 6 cylinder) alloy radiator sitting at home to replace the current genuine 504 radiator. The Commodore radiator will require some modification (outlets sizes changes to suit Peugeot hoses) to fit the way I will like. I will also run a separate transmission oil cooler.
 
Who are you calling an idiot[emoji6]

I once drive a 6 month old Sub Outback through a fast flowing river after following directions via a quad bike rider, I drove slowly through but still managed fold the blade into the radiator and also break a blade.

Later told everyone knows to disconnect the fans before driving through river...was news to me as never driven through deep water before[emoji22]

Was a interesting day to get repaired

Sent from my SM-G900I using aussiefrogs mobile app
 
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