Is it true?

Arde

Arde

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Just read in a book that locking the fan clutch (which is the way I have it in my coupe) shortens the water pump life. Is that true?

Am I the only one that does not trust viscosity clutches and would rather have the fan spin all the time?
 
Arde said:
Just read in a book that locking the fan clutch (which is the way I have it in my coupe) shortens the water pump life. Is that true?

Am I the only one that does not trust viscosity clutches and would rather have the fan spin all the time?
Click to expand...

i do not know if it is true, but it is mechanically reasonable, you are permanently fixing a load to the water pump so i can assume that it will suffer more than when that load is not permanent
 
deQuincey said:
i do not know if it is true, but it is mechanically reasonable, you are permanently fixing a load to the water pump so i can assume that it will suffer more than when that load is not permanent
Click to expand...

Thanks DQ. I need to look at a diagram then.

For a second I thought you shifted topics to the suffering of married vs. single men.
 
I used to lock my fan to the original friction style clutch for the same reason. When i finally upgraded to the newer style i saw that engine noise was reduced and it revved more smoothly. I have a spare clutch that goes in the parts bag for long distance trips.
 
Arde said:
Just read in a book that locking the fan clutch (which is the way I have it in my coupe) shortens the water pump life. Is that true?

Am I the only one that does not trust viscosity clutches and would rather have the fan spin all the time?
Click to expand...

IMHO, yes x2.
 
Anyone go to an electric fan?

Anyone go to a thermostatically controlled electric fan? Quieter, less parasitic loss (?), better for the H2O pump, moser space if mounted on the front of the rad.
 
bfeng said:
Anyone go to a thermostatically controlled electric fan? Quieter, less parasitic loss (?), better for the H2O pump, moser space if mounted on the front of the rad.
Click to expand...


Pretty sure that SFDon advocates this. E36 electric fan set up. Cheap for "pull a part"
Buy 2 and we can have an installation event!
 
+1 electric fan in front of radiator

search board for

"Operation: Arctic Wind"

;-)
 
sfdon installed an aluminum radiator, and the Bav Auto 9 blade fan with a new viscous clutch, and a shroud. Solid temps, even when stopped in traffic for awhile. Good way to go.
 
HB Chris said:
The fan clutch I will be replacing is currently locked and the car runs too cool, the gauge is always at 4:00 or less.
Click to expand...

Mine was between 3 and 4 PM. Until one day it started moving higher than 3PM and got me worried. I started thinking about what happened lately, what food I ate, people I may have offended, and so on and realized it started right after SFDdon stopped by to deliver the M30 head and I showed him the E9. Don has a way of looking around engines with his fingers like my daughter would do in a clothing store, so I jiggled the temperature sensor just in case. It felt like it had some rotational freedom, so I tightened it by rotating it and the gauge went back to where it was before Don.

Since then I do not trust the absolute reading of the gauge, I just look at the derivative.
 
Funny you mention that. Don just redid the cooling system, and on the way home from lunch today my Coupe went 3/4 hot. The needle was jumping from mid scale to 3/4 way too fast to be an accurate reading.

I was thinking air pockets, but then I remembered to keep it simple. I tightened the connector on the temp sensor, put a dab of dielectric grease on it, and then drove around for another 10 minutes. Soild at 3 o'clock with no movement. Easy fix.
 
Note that bmw never again made a 5 bladed asymmetric
fan and only once used a triple core radiator again. Locked
in fans are a kluge. 71 degree tstats are a kludge but note that Saudi
cars got 75 degree tstats up to the late 80's. Bavauto was clever
bringing out the low temp aux fan temp sensor that worked
so well.
And then the 90's arrived and the solution was to lie to the consumer
by skewing the temp gauge reading.
Bastards....
 
From TomP

“use an auxiliary fan from a 325i” Needs to be an E30 thought / not E36. Here’s what it should look like below and here’s one from ECS Tuning albeit for $128 vs. $20 at Pick and Pull (PnP). http://www.ecstuning.com/BMW-E30-325is-M20_2.5L/Engine/ES2091918/

Not hard to pull from PnP. I pulled two and kept the better one / cleaned it up / sprayed it black then returned the other. My new AC condenser is below it in the photo. Based on Don’s suggestion, I simply zip tied the fan to the condenser. It’s holding and working great!
 
I removed my mechanical fan and use an auxiliary fan from an E34 for my cooling fan, as well as a Volvo 2-speed relay for the control system, switched by 90°/99° BMW switches. Low speed has been sufficient for cooling even on the hottest days, high speed has never come on.
 
Not sure if this applies to an E9 fan clutch but on one of my clutch fan equipped cars, the fan clutch is supposed to free wheel above 4000 rpm. The car in question has a 7 blade metal fan. I suspect that the kinetic energy of a spinning fan at redline coupled with the added load of sucking all that air through the radiator might be an issue if it revs consistently at that end of the rev range.
 
Stan said:
Not hard to pull from PnP. I pulled two and kept the better one / cleaned it up / sprayed it black then returned the other. My new AC condenser is below it in the photo. Based on Don’s suggestion, I simply zip tied the fan to the condenser. It’s holding and working great!
Click to expand...

I have never used a part from Pick And Pull for my E9.

I used to go there to get parts for my Volvo 240 and was depressed by seeing that the cars being parted were newer than mine... Rust does not kill cars, mileage does not kill cars, cost of labor does...
 
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