Aux pump/aux fan question - 1985 190E 2.3 8 vlv
 

The shop is putting my 1985 190E 2.3 8 vlv back together after a complete engine and transmission overhaul ($17.00 per hour here in Peru), and I have two general questions about the function of trhe auxillary water pump and the auxillary fan.

1) Is the sole function of the auxillary pump is to divert coolant to the cabin heater core when the heater is activated? Any downside to not replacing a dodgy pump if I don't care about heating the cabin?

2) Does the auxillary fan only kick in when the air conditioner is turned on and the coolant reaches a certain temperature, or does it have a broader reason for existence?

Regarding point 2

I think the Aux fans are mainly for the aircon, but they (as far as i know) may kick in, if the main cooling fan isnt suficcient on a particularly hot day.