I am trying to get rid of an unreliable thermostatic fan switch (probe into radiator fins) that runs my electric cooling fan on my OM617.951 out of an 85 300sd. There is what looks to be some sort temp switch on the thermostat housing that is unused (by me atleat). Is that a temp switch, and if so, anyone know what temp it triggers at? If its around 190-200f then I can hook it up to my fan relay. Thanks.