Yes - the nose piece that bolts to the water pump, the round locking piece that secures the fan to the nose, and the bolt/washer that holds it all together.
Viscous Fan Coupling
- Thread starter Neil Beauchamp
- Start date
I am informed that a slow-to-engage older friction style fan clutch (due to worn friction materials) might still have a little life left - if the friction material is "knurled." This would be using the same technique as knurling piston skirts. Never tried it myself and would not expect this to be a permanent "fix."
There have been a number of threads dealing with fans, fan clutches and pumps. One thread even discusses changing pulleys to alter mechanical fan speed. http://www.e9coupe.com/forum/threads/cooling-fan-upgrade.10468/ http://www.e9coupe.com/forum/threads/viscous-fan-clutch-blues.3653/
I have never measured different fan decibel levels. I would think the 8 or 9 blade fans move a greater volume of air than the 5-blade version. For that reason, I would expect slightly more sound. (Not turbulence.
) Of course the newer 9 blade fan's blades are thinner and have a tapered or sweeping tip that may actually reduce some of the noise.
I had an E3 with a viscous fan clutch that never seemed to engage. The engine ran cool - even with air conditioning. I dreaded the thought of driving in stop and go traffic and not having the fan clutch work - when needed. As added protection, I replaced the fan and viscous clutch assembly with an electric fan used on an American V-8. That fan only seemed to engage when switched on manually. Temporarily blocking the (original) radiator with cardboard would trip the thermostat and cause the fan to run. I eventually replaced the electric fan with the viscous setup and never had a problem over two or three years. For some reason, I think the viscous fan was different from all those discussed thus far. It was not 5, nor 8, nor 9 blades. It was 11 blades.
Elf blade Lüfter
8
9 Blade Lüfter
Fünf Lüfterflügel, Lüfter und acht Blade Lüfter
There have been a number of threads dealing with fans, fan clutches and pumps. One thread even discusses changing pulleys to alter mechanical fan speed. http://www.e9coupe.com/forum/threads/cooling-fan-upgrade.10468/ http://www.e9coupe.com/forum/threads/viscous-fan-clutch-blues.3653/
I have never measured different fan decibel levels. I would think the 8 or 9 blade fans move a greater volume of air than the 5-blade version. For that reason, I would expect slightly more sound. (Not turbulence.
) Of course the newer 9 blade fan's blades are thinner and have a tapered or sweeping tip that may actually reduce some of the noise.I had an E3 with a viscous fan clutch that never seemed to engage. The engine ran cool - even with air conditioning. I dreaded the thought of driving in stop and go traffic and not having the fan clutch work - when needed. As added protection, I replaced the fan and viscous clutch assembly with an electric fan used on an American V-8. That fan only seemed to engage when switched on manually. Temporarily blocking the (original) radiator with cardboard would trip the thermostat and cause the fan to run. I eventually replaced the electric fan with the viscous setup and never had a problem over two or three years. For some reason, I think the viscous fan was different from all those discussed thus far. It was not 5, nor 8, nor 9 blades. It was 11 blades.
Elf blade Lüfter
8
9 Blade Lüfter
Fünf Lüfterflügel, Lüfter und acht Blade Lüfter
Last edited:
Hi Gary -- I know your buddy wants to retain the stock look, but I replaced the tiny little AC fan in my coupe with a 14" SPAL pusher fan (https://www.summitracing.com/parts/SPU-IX-30100382). This fan sits in front of the radiator and inside the nose of the car; you would have to look through the grill to see it.