Viscous clutch question

[deQuincey]

I hate to take issue with someone with as many messages as you have and such a high score, but I am really confused by all of this. Some people say I have a viscous clutch (and so does the BMW Service Manual, apparently) while others say I have friction clutch.

I have the radiator out, I know I could run the motor for a short period without coolant but I am guessing whatever coolant is in the block is gonna come flying out all over creation. (I can find no place to drain the block, either.)

Here is what I see in the blue books (the BMW Service Manual for 2500-3.0CSi). I have underlined why I think my clutch fan is not working.
View attachment 107160

ok, i understand, i am not english, so my messages may sound odd to you

i have seen that you might have now clear what happened to your fan clutch, life is long and mechanics are unpredictable

BTW, your listing from the book mentions the cut-off speed, you can run that test to know if your clutch is still sound

 

[deQuincey]

I hate to take issue with someone with as many messages as you have and such a high score, but I am really confused by all of this. Some people say I have a viscous clutch (and so does the BMW Service Manual, apparently) while others say I have friction clutch.

I have the radiator out, I know I could run the motor for a short period without coolant but I am guessing whatever coolant is in the block is gonna come flying out all over creation. (I can find no place to drain the block, either.)

Here is what I see in the blue books (the BMW Service Manual for 2500-3.0CSi). I have underlined why I think my clutch fan is not working.
View attachment 107160

yes, from spin freely to it can not be turned there is a whole world of possibilities, as to address for wrong function

i would say most probably your clutch is ok, but cut-off speed test is the way to check it

 

[Luis A.]

He says when he tries to spin it it doesn’t spin freely; it turns the belt and with it the pump alternator pulleys. It IS locked up. Get a new one.

Separately, but related, this version of the viscous clutch is not temperature sensitive. For my taste, it spins too audibly. I moved to the “spin-on” clutch (it mounts on a different water pump that has a big nut) which is temperature controlled such that it only spins faster when it senses a high enough airflow temperature to produce more cooling.

BTW, I therefore have a new water pump that I no longer need listed in the ads if any of you need it for your “through-the-hole” clutch.