"Evil servo" question

[Argospete]

I have been reading as much as I can about the "evil servo" and how it functions from this forum. My question: If I never use the heat option and keep the temp wheel on the cool side the hot coolant does not get pumped by the aux water pump into the servo and then to the heater core which produces the heat. Therefore, the possibility of the servo every leaking coolant would be avoided. Does that sound right??

[kerry]

No. There's always coolant in the heater hoses and movement of that coolant does not require the auxillary pump.

[rhodes2010]

First off, the servo is not so evil. Just misunderstood and not preferred by many.

I have the aluminum body servo and rest peacefully.

The servo always has coolant in it. As stated in the previous post.

To avoid the servo and coolants leaks you can easily bypass the servo.
While I waited for a new servo I bypassed for a couple years.
In the winter I would hook up to heater core for heat.
In the summer just bypassed completely.

Several threads here talk about installing a manually operated valve on
that water connection. Nice idea.

Does your servo leak now ? Or do you have unwanted heat in the cabin ?

[Argospete]

But if you don't allow the coolant from the block to reach the servo how could there always be coolant in the servo?? Bypass the servo and return the coolant going out of the block to the line going back into the block? You will not have heat?? Would the Ac still work properly everything else being the same???

[kerry]

Originally Posted by Argospete

But if you don't allow the coolant from the block to reach the servo how could there always be coolant in the servo?? Bypass the servo and return the coolant going out of the block to the line going back into the block? You will not have heat?? Would the Ac still work properly everything else being the same???

The only way you will stop coolant from getting into the servo is unhooking the heater hose that goes to the servo. Then you wont have heat. I don't know if all the AC features would function with the heater hoses removed from the servo. There is a coolant temp sensor in the servo but I don't know if it is necessary for the AC functions.

[thorsen]

Originally Posted by kerry

I don't know if all the AC features would function with the heater hoses removed from the servo. There is a coolant temp sensor in the servo but I don't know if it is necessary for the AC functions.

The ETR runs the evaporator at a constant 38*. Heat is added (via the servo) to keep the interior at the temperature selected on the thumbwheel. With the servo bypassed then the interior will be as cold as it wants to be. The longer you drive the colder it will be.