Question about 1999 Mercury Cougar

1 Answer

My sons 1999 mercury cougar 4 cyl gets hot and blows anti freeze out of the bottom of the engine. It doesnt appear to come from the over flow hose but it doesnt leak all the time either so its not a hole in a hose. We replaced the thermostat and the radiator cap seems to have the correct pressure. Any clues what could cause it to blow the radiator fluid out from underneath?

Posted by on


1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Mercury Master
  • 4,369 Answers

Thermostat stuck closed

Posted on Nov 21, 2009


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

I have a 99 mercury cougar, I am not getting any heat and the oil guage is reading in the red zone

Check that you have the full amount of anti-freeze in the expansion tank AND that it tests to -34 degrees below zero Fahrenheit.Weak anti-freeze allows boilover and then your heater won't work when level is low or it air locks.ALSO,your thermostat can be stuck shut and that will cause the above problem of boilover.
This boilover can break down your oil by the engine overheating.So check your oil level and change your filter. don-ohio

Oct 16, 2011 | 1999 Mercury Cougar

1 Answer

Heater is blowing cold

Thermostat stuck open, heater core clogged, or heater control coolant flow valve stuck closed. With the engine at full operating temperature check the hoses at the firewall going to the heater. If one is hot and the other is cold or just barely warm, the heater core is clogged or the coolant flow valve is stuck closed. If neither is hot, you have a thermostat stuck open and need to replace it.

Jan 21, 2011 | 1992 Mercury Cougar

1 Answer

Cooling systemon a 1999 mercury cougar want to

it dont matter what engine we talk about,the closer to the top of the engine the the better,it might be the top hose etc,,,,.start the engine and let the air out of the system it will be very hot so watch outonce the air bubbles stop then lock the system/tighten the nut,etc.adrian,,,,

Jul 26, 2010 | 1999 Mercury Cougar

1 Answer

How do i know if my thermostat is not working in my 1999 murcury cougar

After engine is warm be careful and feel the upper and lower coolant hose's they both should feel the same ( careful could be hot ) if only one is hot bad thermostat. Also feel the are blowing thur your radiator should feel warm to hot, if cold bad thermostat.Good luck

Dec 02, 2009 | 1999 Mercury Cougar

1 Answer

Little to no heat from 2002 Mercury Cougar. Thermo- OK, Change over- OK Anti Freeze- OK

your system is airlocked.You should have a bleeding screw at the top of the engine if not loosen a top hose and let air out then close making sure water supply is topped up .adrian;;;;

Nov 12, 2009 | 2002 Mercury Cougar

1 Answer

Low Heat on 1999 Mercury Cougar

I had the same problem with my 199 cougar 2.0 4 cyl.
The problem was air in the cooling system.

I had to bleed the air out of the system, and now the heat
works much better.

I put a flushing tee between the back of the thermostat and
the heater core, and made sure that water flowed out of there.
Then I disconnected the small hose from the top of the coolant
resevoir, and poured water into it using a funnel until the coolant
level started to rise in the coolant resevoir. Then started the car, left the radiator cap off, and let it come up to temperature (thermostat open)
then over a period of about 5 minutes, periodically "goosed" the engine to clear any remaining air bubbles.

The heat is MUCH better now.

Oct 17, 2009 | 1999 Mercury Cougar

1 Answer

Heat doesn't always blow hot

sound like you are low on anti-freeze, when engine seed increases the coolant will flow

Mar 29, 2009 | 1999 Mercury Villager

2 Answers

My 99 cougar only blows cold air the hoses are hot,

maybe your thermostat is stuck open, you may need a new thermostat.

Dec 05, 2008 | 1999 Mercury Cougar

1 Answer

Heater not getting hot!

Could be one of many things, first check your antifreeze concentration,s/b 50/50 mix,my sis had the same problem, she used straight anti freeze, need water to hold heat.

Nov 20, 2008 | 1999 Mercury Cougar

Not finding what you are looking for?
1999 Mercury Cougar Logo

Related Topics:

110 people viewed this question

Ask a Question

Usually answered in minutes!

Top Mercury Experts


Level 3 Expert

76846 Answers


Level 3 Expert

5546 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22246 Answers

Are you a Mercury Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides