coolant thru heater core: block or bypass? - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Cadillac84 · 06-07-2005, 19:20

I have a '97 Town Car and I'm bypassing the heater until I have the time and inclination to take the instr panel and all below out to get my hands on the A/C blend motor and door.

I am wondering if coolant flow through that circuit is necessary or would it be OK to simply block it.

My old Caddy had a vacuum operated cutoff valve that stopped coolant flow to the heater core when A/C was on Max and temp set to 60 degrees.

If the LTC has such a thing it is invisible (inside?).

Would it be OK to simply block the coolant supply with a valve? Or is the flow needed for engine cooling?

Thanks in advance for any input/advice.

ebxr8240 · 06-08-2005, 00:31

It would possibly be easier to join hoses together..Or double one around to the other outlet so its still able to circulate....

Cadillac84 · 06-08-2005, 08:11

Thanks for the reply --

Doubling back is not a good option on the Town Car because it might be easier to pull the engine than to get at either of the hose ends -- well, I exaggerate, but . . . .

I had bought a 5/8 x 3/4 adapter thinking the hoses were different size -- Nope! both 3/4"

So, I've got it hooked back and I'll have to do it another day. Problem is it takes a good while for the thing to get cool enough to open up. Hate I'm going to have to do it all over again.

I think I'm going to get two 3/4 x 3/4 couplings and a short piece of 3/4 hose and make a loop rather than try to bend those nice formed hoses into pretzels.

I've read some in the service manual for a F150/250 truck with the 4.6L engine and it sounds as though they expect the heater loop to be open at all times. I'm not going to take a risk of overheating the engine to postpone spending $500 to get someone to change the blend motor.

Thanks again.