JackAysJake

I have a 98 navigator.

Took it to one shop who diagnosed it as a bad water pump. Took it to another place who flushed it and was lost. Took it to Ford who says the blend air is working but the cores are clogged.

Replaced the front and rear cores, flushed the system, replaced the water pump for the heck of it while the system was drained and found the blend air door was cracked not allowing it to open and closed. After all this, its only putting out a little bit of heat. the hoses are barely getting warm. Whats the deal??? Next I guess im going to replace the heater control valve which is what I have been thinking it was all along.

Bert

There isn't a heater valve on your vehicle. If the hoses aren't getting hot, there's a problem in that area. What's the engine temperature? Does the radiator hose get hot?

__________________
Bert

JackAysJake

The engine temp guage reads about 20% which seems a little cool to me. Seems like I should be running into overheating problems, but due to the fact that im not kind of confuses me. Ill have to get back to you on the radiator hose getting hot. What could cause the engine to run a little cool? And maybe due to it running cool its not opening the thermostat?

Bert

If the radiator hose isn't very hot, the thermostat is opening to soon or it's stuck open. Make sure to run it quite awhile before you check the hose temp.

__________________
Bert

JackAysJake

Well just checked and the hoses by the radiator are getting hot. Need to find a diagram to see what hoses are supposed to be where. The thermostat was just replaced. Doing the same thing before and after replacement.

JackAysJake

Ok Ford says there is a flow problem. They said that the upper radiator hose is about 160 degrees and should be over 200. The thermostat housing is about 170 degrees. They said there is a flow problem. Stop leak was in the system, What areas could easily clog?

JackAysJake

Well approximatley $1300 later I have heat in my navigator. Come to find out the truck has a heating system then a separate cooling system. Kind of. It has the radiator, thermostat, water pump. That was the cooling system. Now for the heating system: The same coolant that runs through the cooling system runs through the upper intake and out a line that goes directly into the front heater core. This returns from the core and goes straight back to the rear heater core. Returns from that core and goes to a metal line on the back of the engine. The metal line bolts to the side of the engine and hooks into the water pump for a return. My problem was a chunk of sealant stuck in the metal line on the rear of the engine. This was purposely put there. Guess there was a leak and I ended up replacing the leaking part. The water couldnt return.

Bert

Wow! That was an expensive fix. The man-made problems are the hardest to find. When things go bad on their own, it's can be found a lot easier. Not always real easy, but can be figured out in a normal sequence. You wouldn't expect it to do that on it's own. Glad you got it fixed, and thanks for the update.

__________________
Bert