Coolant pressure is high after I shut engine off.
Asked by category5jc Jul 07, 2013 at 04:05 PM about the 2003 Lincoln LS V8 Premium Sport
Question type: Maintenance & Repair
I have a 2003 LS V8 and just replaced thermostat housing, thermostat and coolant resevoir. The temp guage is right where it is supposed to be but when I shut engine off, there is high pressure in the system and if I dont bleed it out it leaks coolant. Also, it appears to boiling in the resevoir. What is causing this? I checked oil and it is clean in case the head gasket was blown and leaking coolant into the oil.
3 Answers
the high pressure in the system is normal (15psi), replace the reservoir cap and check again.
Agreed. I forget the formula but for every pound of pressure the system has, it raises the boiling point of the coolant. 15psi raises the boiling point considerable and NEVER open a cap that has pressure on it - I have the scars to prove it! The coolant instantly boils as soon as the pressure is relieved and you and everything around you can be coated in this 212+ degree substance that is slicker than snot and doesn't come right off - unless your skin is going with it. Sorry. Replace the cap and check for leaks. Use the proper antifreeze and mixture (usually 50/50).
My car is doing the same thing Ive replaces the coolant reservoir 3 times the climate control module 2 times and replaced the t hose and thermostate and housing. no water in the oil, not burning and it runs fine in fact to good for 164000 miles. Im doing a C02 check today why else would the system be vapor locking. My climate control module works fine than all of a sudden it blows out cold air than next extremely hot air. Scared to say no tranny issues yet but that could pop up today.!
