I have read about the need for the fan clutch to be serviced if it does not hold tightly enough after warm up. Mine also shows dirt on the fan blades which I am told is an indication of failure. My engine is running a little hot here in Miami so I think this may be the reason. I believe the auxiliary fan is also working properly. The heat exchangers seem to be clean and free of crud. My gauge reads at the 5/8 mark but creeps up toward the 3/4 mark in traffic with the AC running. (I realize these marks are not indicate zero to full - just thought it the easiest way to refer to there the needle sits). Everything seems to be in position with regard to the air flow and I have done a coolant flush within the past few thousand miles following the procedure for filling. I have used an infrared thermometer and get high 190's on the crossover pipe and thermostat housing area. The top of the engine block is in the 220's. I was told to focus on the water temperature readings.

So about the fan, is this a simple repair?

 

Its pretty easy and inexpensive. It's a little tedious removing the fan clutch assembly without damaging the radiator fins. Install a piece of cardboard in front of the fan to protect them. The attachment nuts can be loosened using belt tension to hold the pulley. Then back off the nuts in steps.

 

Thanks, is there any harm in mounting the fan without a clutch? As long as you keep your limbs away from it.... why not?

 

The clutch bolts to the pump. The fan to the clutch. Fan holes will not align with the pump studs. You'd need to manufacture something to replace the clutch. So, It's not really a practical solution. Some have replaced it with an electric fan. I have not.

 

 

Way back when there was a time that cars had fixed fans Mostly OK!! But, busted blades did cause havoc. and though rare, it did happen.

As to the use in a modern car. NO!!!

I'm not convinced that yours is done for. Your IR readings are OK. .

Check for debris between the Radiator and AC Matrix. I suspect you will fid tons of bugs and other debris/

And, the new clutches are not really that expensive...

Carl

 

Hi gccch

Replacing the Fan Clutch is fairly simple (in the scheme of things) and not very expensive (Try 'Rock Auto') although you could well find it a bit of a PIA job if you have never done it before

But do take Care not to 'Ding' the Rad and do make sure that you DO NOT accidentally turn the Engine over the WRONG WAY! or that will really go and spoil your life

I have always found it best to slack the Belt right off, so you can turn the Fan round to get at the Bolts underneath and use another Spanner to Stop the Fan Revolving while you undo them

Maybe its not the Fan Clutch, that is causing your overheating problem as it could be a the Thermostat not opening?

 

Well, its not that it slips at high RPM. It actually releases its hold between the movable fan and the fixed hub through a temperature controlled bimetallic spring. At cruise or high RPMS, colder air is entering through the radiator and is felt at the clutch thermostat/bimetallic spring. I'm not sure on this particular clutch hub, but most will have a bimetallic spring exposed in front which the outer point is fixed and the inner wound point is attached to a small shaft which ports fluid, similar to a torque converter or a viscous coupling. When hot sitting in traffic, you should be able to hear the roar of the fan as the clutch couples up and almost directly couples the spinning hub with the spun fan. This is to pull more air through the radiator. As you drive off and the spinning fan no longer needs to spin that fast, the oncoming fresh air cools down the bimetallic spring and the shaft turns as the spring coils tighter as it cools which disengages or begins to uncouple the driven fan. All day long it does this . I have removed fans and clutches on cars and have cleaned up the spring which sits in front of the clutch facing the oncoming air temp. If this has it, clean the spring and work the shaft back and forth and make sure it's free to spin. One direction is free and the other direction is lock up.

 

You can buy a heavy-duty clutch which engages sooner and longer then OEM the part number is in Palm's book. I'm at work so I can't readily find it.

Your fan should spin no more than 1/4 turn while hot with two fingers applying a good amount of force. Mine barely moves the width of a fan blade after warming up (new clutch last year)

 

OK, based on the last comment I need a fan clutch.
I also just got done cleaning out between the radiator and AC heat exchanger. As predicted above this was a mess. I got it pretty well cleaned out and hosed through. Long job with a lot of things to remove to access. On the way home it seemed to peak at the "5/8" mark on a sunny Miami 78 degree day with the AC blowing. New fan clutch will probably make a difference.

 

Installed my new fan clutch last night. Not a bad job, just hard to reach sometimes. Almost had a problem as I was short cranking the engine to get the partially loosened fan in position to get to the bolts on the bottom side and the darn thing started up. This being the car that will crank and crank when I want it to start! haha.. no damage done, luckily. Rookie mistake.

Will get a good test today in Miami. Should get up to 80 today.

 

gccch.. same thing happened to me, gave me quite a fright as I was not expecting that.
Know I now it was due to the fuel rail a full pressure where it is not normally when we start from scratch / cold.
Turning on and off the ignition to spin the fan, the pump runs each time.

 

Car does not seem to run any cooler.

I measure 98 deg C at top radiator hose, 107 C on thermostat housing, 90 at lower radiator hose.

Hopefully these are in range for a 81 degree Miami day after sitting in traffic with the AC running. Summer may be a different story down here.

 

Have you already replaced the thermostats and made sure that the cooling system is properly bled of air?

 

I have not changed the thermostats. They are likely original. I have replaced the coolant and properly filled it per the manual.

 

Did you do this on a steep incline nose up? then go rip down the highway and back?

 

no, that's not the procedure in the manual. I took it 1500 miles form Michigan to Miami. Does that count?

 

Lol. Thats more like a grand tour. But refilling with the nose up is critical.

Though if you went that far I'm sure it bled properly, If it was me I would double check the coolant tank because I'm paranoid about overheating.

 

I have checked it recently and it won't take any more. I'm pretty sure it's full. And the driveway I filled it in did have a slight upward slope.

 

Good that you cleaned the radiator externally but a week's pay says it's partially clogged internally. Very common.

IMO, remove it for a professional cleaning at a radiator shop.

Cheers
DD