How do you replace the thermostat on a 1987 mercury grand marquis?

Answer 1

First you need to remove dash pad and loosen the right side of dash, On engine side of firewall remove the bolt on left top corner of evap housing and the nut on top right, there is another nut under the case on the same stud, top right of evap. that nut is hidden there and could give you a headache as to why the case wont budge once you remove the two nuts on bottom of case in passenger compartment. there is a bolt under the wiper motor on the fire wall that aso needs to come out. Hopefully this helps you

Answer 2

First, drain the cooling system, remove the radiator hose, detach Êthe thermostat cover from engine, and remove the thermostat and O-ring seal. Then clean the sealing surface, install the new thermostat and its O-ring seal. Alternately tighten the housing, and connect the radiator hose.Ê

Answer 3

I don't know, the 9991 Grand Marquis has not been built yet, but if I know Ford, they will put it somewhere where it will be tough to access similar to the thermostat or the 2nd spark plug from the rear passenger side. Autozone has a do it yourself feature on the internet that has a lot of instructions for that kind of stuff; they will want you to register first.

Answer 4

1. remove positive cable off of battery
2. remove plastic trim guard under glove box
3. remove glove box
4. remove ash tray completely not remove the metal frame)
5. remove trim on passenger side that touches the windshield and dash
6. remove the trim covers on the left and right hand side of the dash ends,ther are two bolts each on drivers side loosen top bolt and remove bottom bolt
7. on the passenger side remove both bolts
8. on the dash,remove the trim that is at the window defogger area,remove the three bolts
9. if you wish to drain out the antifreeze ..you can do so at the radiator
10. the two hoses for the heater core (in the engine compartment) have spring clamps that are probable upside down. You will have to force them around in order to remove them.
11. be sure to loosen the hose off of the heater core..i used a pry bar and some twisting
12. now here is the way to get it out with out the removal of the dash/and steering column/instrument cluster/key cylinder etc. or cutting of the dash...you will need a small floor jack available.you may be able to use a bottle jack with some wood shoring under it for height...
13. i placed the small floor jack directly under were the ash tray was...and slowly lifted the dash with the top of the ash tray metal bracket...you have to adjust sow that the heater core will come out..
14. you will see the heater core housing. It will have a access panel with the device that opens the blending door for heat/a.c...mine was white, you can start car (before begining any of ths process)..and turn the ac/heat control knob. you will see a metal guide on this control going up and down..this opens up the blending door inside.
15. remove controller/metal guide/spring and plastic retaining guide.
16. you can take a plastic zip tie or duck tape and be sure that before you remove the access panel the blend door lever is push up all the way..it is breakable...and this will keep it out of the way when pulling out and installing heater core
17. once the access panel is removed...go to the engine compartment..and push in the in and out heater core pipe that is sticking out..i used a pry bar to do this...
18. go back inside and lift the dash only enough to remove the heater core...it is close..but it does work...as a fyi..there are two wire harnesses under the glove box area were it was bolted to..you may want to pop them out of the retaining plug areas as this will allow the dash move height..and more access to the heater core..
19. after placing the new core in i put in two bolts in the access panel..so when i installed the heater core hoses it kept the heater core in place.
20. just work in reverse from this and you should be able to do in 3 hours

Answer 5

You have to remove the dash assembly to get the heater box out. That's the entire dash assembly, not the instrument cluster or the dash pad or anything. The WHOLE dash has to come out. From there, it's a piece of cake. Just drain the cooling system, unhook the two heater hoses, remove the attaching nuts along the firewall in the engine bay, remove the big sheet metal screw that holds the heater box up against the cowl vent, remove the three cables and snatch it out of there. Then pop the clips off that hold the heater box halves together, remove the hoses from the heater core and put the new one in. Installation is the reverse of removal.

Answer 6

Hey John==It is pretty complicated so get a manual on your car from the parts store or AUTOBOOKSONLINE.COM. It will have pictures and everything. GoodluckJoe

Answer 7

For a 1995 Marquis it requires a skilled mechanic several hours to drop steering column, remove entire dashboard, disconnect airbags, just to get to the heater core.

Answer 8

When you raise the hood you will see a top marked coolant. Make sure car is cooled. Using a funnel slowly pour the coolant till you have reached the line marked full.