4009TVM

I have '06 v6 my daughter is driving. Started spilling coolant. Replaced the reservoir cap. Fan died, replaced with OEM recently (fan had gone bad BTW). thought I had it done. Overheated again, replaced thermostat. Overheated again, replaced reservoir cap with Motorcraft cap. Overheated again, but no coolant appears missing. Thought it could be the water pump but garage says they can't say it is bad per the usual reasons. They also won't work on it anymore since they "can't" fix. Coolant was flushed twice and replaced.

Took to another shop last night, they checked it out and could find nothing wrong. Car has around 106K miles on it. I don't hear any unusual noises when i am around it. She now is afraid to drive it. Obviously I don't want to replace the water pump if I can't prove it's bad. What can I do?

7 UP Mustang

Did you replace the radiator pressure cap? You said you replaced the reservoir cap, I guess you mean the over flow reservoir cap. Could be a bad pressure cap or the radiator is restricted due to build up of mineral deposits in side the radiator.

Good luck!
Larry

4009TVM

fluids were flushed twice by garage during this ordeal, so don't think radiator is clogged up. no fluids were leaking last night when it overheated. two years ago the temp sensor housing started leaking and was replaced, doesn't leak now BTW. No idea what to do next and sure don't want to "just" replace a waterpump.

JimC

You replaced the thermostat, but how about the thermostat housing? Did you check it when you put the new thermostat in? The housing usually splits on the back side and because of the way it drips it can look like a water pump leak.

Nuke

Possibly this^^^

The S197 V6's are notorious for cracked t-stat housings. Since you didn't specify where it's "spilling coolant" from, this could be it. Otherwise, I'm thinking blown head gasket.

Matt's 95 Stang

Normally you will see coolant in the oil or oil in the coolant if you blow the HG. Easy way to rule that out is to see if the oil looks like a milkshake, if not its not a HG. Could be the thermo housing like said before, or the radiator cap is busted and needs to be replaced.

Matthew

Nuke

If there's water in the oil, you'll usually see "baby poop" on the underside of the 710 cap... sorry, that was upside down... the OIL cap.

157dB

http://iihs.net/fsm/?dir=180&viewfil...%20Cooling.pdf

JimC

When my car blew a head gasket (while still under warranty) the oil looked fine. So that isn't a foolproof test. A cylinder compression test will tell you where the leak is though.

jimkaray

Right, the head gasket can fail between the water jacket and the cylinder without impacting an oil passage. Usually it not fixed it will get bad enough over time where it will open up into both cooling and oiling passages. Check on Amazon for a tool called , it detects the presence of hydrocarbons in the cooling system and will verify a bad head gasket.

As far as flushing goes it won't do much to help a clogged radiator. Look at how thin it is, once they've corroded up inside you can't flush it out. If you remove the fan you can move your hand around and see if its hot all across it. Cold spots are clogged up and no hot water is getting through there. A infrared Heat gun would work too.

Is it clearly overheating - dumping fluid, running like crap and should be pinging badly. If not maybe just a faulty gauge or a coolant sensor.

Last thought, the water pump is easy to get at so pull it off and check it out if nothing else bad can be found. Sometimes the impeller breaks up and there is nothing left to circulate the fluid.