2011 Lincoln MKS - Overheats

2011 MKS keeps overheats within 3-4 mins. Thermostat , cooling fan module have been replaced. What could cause ththis.

just some thoughts…
make sure the overflow coolant cap is sealing properly.
did you blead the air out of the system?
a faulty water Pump can cause over heating.
and so can a leaking head gasket. any milky color in the oil or coolant?
white smoke out of the exhaust?

There all kinds of things that could cause this overheating . But it needs to be towed to a shop and have it fixed ( Of course ask for a repair price before they do any work ) before you destroy your engine by guessing and just replacing things.

When the engine is cold, remove the pressure cap from the coolant reservoir.

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If it’s low/empty add water.

Start the engine, and as the engine idles watch the coolant in the reservoir.

If bubbles start to appear, it’s an indication of a blown head gasket.

Tester

The first things to check

  • Is Engine coolant level low?
  • Are the engine fans spinning like crazy ( when it is overheating)?
  • Is the thermostat stuck? A shop might be able to do a quick check on this by feeling the temperature of radiator hoses as the engine warms up. Otherwise the part will have to be removed and tested in a bath of hot water.

If it is badly overheating after just 4 minutes from a cold start, my guess, stuck thermostat.

Any leak, no matter how small can cause low coolant and stop the coolant recovery system from working. A clogged radiator or bad water pump as others have suggested.

I once saw a Dodge minivan that overheated only between 45-55 mph.It had been in an accident and repaired by the Dodge dealer. It had many receipts for attempted cures for overheating, includind two radiator replacements and a water pump, all to no avail.

Finally it was taken to a small independent shop who quickly and correctly diagnosed it. The fan wires had been cut in the accident and whoever has spliced them at the dealership had crossed them so the cooling fan was running backwards. At highway speeds, the air coming in the grill overwhelmed the fan and at low speed the fan overcame the air coming in the grill but around 50 the air was not moving through the radiator.

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Yeah, the above. We will hope it’s not the head gasket and just no coolant due to a leak. Now in the very cold winter day my old Lincoln did over heat in a few blocks due to frozen water in the cooling system. Not enough antifreeze.