Cooling Fan Clutch question

[djvanyel]

I didn't see this answered anywhere else, so thought I'd post this to the group for those who might have come across this quandary:

I was doing some preemptive research into a new water pump for my '87/'83 (just in case) and noticed pretty much everyone recommends replacing the fan clutch at the same time.  I think I've narrowed down the proper water pump type (although I'm not decided on a good replacement brand), but there appears to be more than one type of fan clutch listed.  They appear to be either:
-Non-thermal (CW/CCW)
-Thermal (CCW)

My instinct says a thermal clutch is correct, and from the engine's/driver's perspective, the rotation is CCW but, as is often the case with obtaining parts, I'm not 100% sure.

Anyone know what the applications of the two types are? 

[T5258]

using the 84 manual for reference, the serp belt equipped 4.2's have a reverse rotating water pump & fan clutch....as far as the clutch type, the only description given is that it is a Tempatrol drive, which is viscous, so I'd agree with you & run with a thermal type.....

[vangremlin]

I am looking at a new fan clutch myself, and came across the following information from the Hayden website

http://www.haydenauto.com/featured%20products-fan%20clutches%20and%20fan%20blades/content.aspx

[BenM]

Standard should be CW, reverse should be CCW, looking at the front of the engine. I guess it would depend on how the manufacturer defines CW and CCW.

Heavy duty cooling got the thermal clutch along with the three-row radiator.

Replacing the clutch is good advice, if it's worn out the vibrations will wear out the pump faster, usually one causes the other to wear out as it goes.

Before you install a new pump adjust the clearance on the impeller. It should be less than .030 without rubbing. If the impeller is too far away from the casting it's efficiency drops drastically.