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Thermostat housing, How-to, but need detail.

17K views 22 replies 10 participants last post by  amc49 
#1 · (Edited)
My car is still overheating after changing the themostat housing... what is going on...
and one can help again?

Guys,

I think my Thermostat housing is leaking... and I have a graph here. I know I should be able to do it... Still I want to have some more detail from guys who did it already...

Plus, this graph is going to help the rest of people who need help with the Thermostat housing. See bottom!

Thanks
Steven


 
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#2 ·
i got a deal from the dealership as well...
8592 ASY with O-ring to the block from $58.76 to $41.13
the O-ring for the thermostat W700319 S300 from $8.00 to $5.60

Now I only need some experience talk and I will get my hand dirty...
Just want to know detail steps and what difficulity I might have and so on...

Thanks guys...
and hope you can sticky the graph... i think it is not on the How-to anywhere.
 
#3 ·
  • Park car and get her on jack stands
  • Put drain pain under radiator and drain that sucker via drain plug on bottom drivers side
  • Disconnect hose that attaches to the front of housing.
  • I believe there is a sensor there too..disconnect wire to sensor. Be careful though, the heat can make that plastic brittle
  • Unbolt housing from block via 3 bolts on side of housing
  • Remove housing
  • Take front piece off the housing to remove the thermostat. **Take note of the little hole on the front/top of thermostat. When you put it back in, this hole should be on the top
  • Remove tiny clips from silver plugs in housing and swap them into the new housing. You may have to replace the o-rings, mine got perma-sealed to the housing from heat and chemicals and needed to be replaced.
  • Remove clip and sensor from housing and swap to new housing...again, be careful. Heat can make plastic brittle.
  • Put thermostat in new housing (with hole facing u)
  • Put new oring in place
  • Bolt housing to block
  • Re attach hose to front of housing
  • fill up car with new coolant/water
  • FIN!!




Extras I might recommend, o-rings for the silver plugs in housing and possibly a new sensor. You might want to take this opportunity to switch to the lower temp Thermostat, if your mods dictate.



hope this helps
 
#4 ·
One more thing....the most common cause for a leaky thermostat housing is a leaky valve cover gasket!

The oil will seep out and down the side of the block. It gets in between the block and the housing and hits the rubber O-ring, causing it to swell. Then the swelling causes the plastic area around the O-ring to crack and cause a leak.

Not saying you have to do this as well, but it would be a good idea to look for evidence of this happening. Keep it wiped down and if you think this is your cause, think about replacing the valve cover gasket....its fairly cheap and easy to do.
 
#5 ·
i have the valve cover gasket in three months ago...
now i have already replace the housing...
the housing itself was not crack... but shady... so i got new one in...
new thermostat and ring...
coolant flush and new coolant!!
all ready to go...!!
 
#9 ·
Today... I drain the coolant again...
because I have 100% coolant in it...
before I put water, i drove for like 20min hard no problem...
but when i turn the A/C on... it starts heating up
so I put 50% water in there... and us 50/50 coolant...
let the car run and crank the heat up to fill the coolant up...
15mins later, drove it really hard with A/C on max...
and it still over heat...

SpeedOften, my themostat is brand new... but i will go ahead and check it...
should I get the advance auto parts one or Ford one?
Iminhell, my fans are both working... thanks for chaning the 56k... because it is like 3mb..

btw... i am so stupid to twist the radiator drain cap to broke off...
want can I do?where can I find another plug, or can I even find another plug?
 
#12 ·
hEaT,
I will try to make it over heat, and then check the fan...

but i still think it is the new thermostat, because it was an open item... should I go with the ford oem one from the dealership?

thanks,
Steven
 
#13 ·
ok hEaT,

I have driven to school and make the engine hot enough to make the fan turn on.. and I max out my A/C, seems the fan on the drive side is blowing hard... dono about the pessenger side yet... coz i am late for class... so i cannot check it.... and it was not even a mile drive... my car heat up completely... i seriously think my new themostat is not working...

guys more idea please

best regards guys,

Steven
 
#15 ·
Have you replaced the thermostat yet?

If you do, the OEM Ford one should be fine. No need for a cool one unless you want to seriously track the car.

You can test your current one this way:
http://www.focushacks.com/index.php?modid=60

I'll have to pop my hood and look, I'm not sure how the fans work. One may be the A/C fan and the other a two speed, or one is low speed and one is high speed. I'm not quite sure, but I'm guessing the first. If it is the first, it sounds like your resistor pack is shot.
 
#16 ·
i really don't mean to jack this thread, but i'm glad i looked at it cause now i can get a lil more specific as to what i'm looking for. That hose that comes from the firewall and goes to the thermostat, the hose in between that attaches to the hose coming from the firewall, #18472, what is that hose called because i need to replace it on my car? thanx
 
#18 ·
the OEM ford part...
the parts department gave me a wrong part...
that is why it won't fit...
and i believe my friend mount the themostat wrong direction..
which should be the reason why it is over heating...
 
#20 ·
No vacuuming needed, make sure small hole in stat faces straight up to match the small hose entry in the front cover. The system pretty much bleeds itslef and quick then.

On Focus cars BOTH fans come on as one, they are both on low or both on high as needed.

The stat goes in with the smaller disc end toward back of car. Again, small hole in outer edge faces straight up. That hole may have a loose BB or little poppet trapped in it, I always take it out on mine. That stops it from getting stuck from corrosion later in life.
 
#21 ·
I'm having the same problem. I have replaced everything but the radiator as far as the cooling system is concerned and it overheats when I use the ac...it also over heats when using Google the heater occasionally...
Heater coil has been replaced...I belive the problem is that there was stop leak in the system before I bought it...and I've flushed the majority of it out and replaced parts but it still stains everything red
 
#22 ·
...it also over heats when using Google
Umm, OK...that's a new one. [:)]

"Everything but the radiator" replaced. What parts specifically? If you just replaced failed components, such as the cooling fan resistor, the car's wiring harness may need attention too.

"Heater coil" = heater core, perhaps?

Might get more responses if you start your own thread with more details specific to your situation.
 
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