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Thermostat housing upgrade

24K views 40 replies 11 participants last post by  Svtbruh03 
#1 ·
Is there a how to for the thermostat housing upgrade? I looked through the how-to, and could not find one. I have just done mine, and would be willing to post, if you think it is needed.
 
#2 ·
Here is a quick how-to for the upgraded thermostat housing from Tousely Ford.

The kit the send is complete except for the brass plug you will need to fill the extra port on the housing.

Make sure car is stone cold before doing this.

1) Remove battery cover and disconnect battery and remove.
2) Remove battery tray.
3) Drain antifreeze from radiator. (Loosen reservoir cap to help it drain)
4) Remove coil cover & spark plug cover.
5) Loosen vent hose from valve cover.
6) Unplug connector from coil pack (I used a little flat head screw driver to loosen the clip.)
7) Unplug coolant sensor connector.
8) Unbolt capacitor next to coil pack. (7mm socket)
9) Unbolt coil pack. (I did not unplug the spark plug wires, it moves out of the way easily once unbolted.)
10) Remove coil pack bracket (3 Torx bit bolts, there is also a wiring harness attached to the bracket, loosen the vinyl clip, and you can then pull out the bracket.)
11) Remove all four hoses from thermostat housing. (I used channel locks, and the battery tray being removed made this a lot easier, I tried it once with it in place.)
12) Unbolt thermostat housing. (3 10mm bolts)
(As a side note, I had very little antifreeze drain out when I took the hoses and thermostat housing off, thank goodness, I hate a mess. I had a drip pan in place just in case.)
13) Clean head surface where thermostat housing is mounted.

I put the thermostat housing together before I mounted it on the car.

14) Install brass plug into extra port, using a little Teflon tape, and snug it up tight.
15) Put o-ring on thermostat, slide it into housing, and put on thermostat cap, tighten down the 3 supplied threaded screws. (This is a god send, next to the self taping screws on the original housing) You don't have to crank these down, they stop when they are tight enough.
16) Install supplied temp sensor. I used a little Teflon tape on this as well. 19mm wrench fits the sensor.
17) Bolt new housing onto the block. I could not find exact torque specs on this..I called Steve at Tousley, and his recommendation was to use a 1/4 drive ratchet, and tighten them until snug. (Worked like a charm.)
18) Back fill the cooling system with the hose that attaches to the back side of the thermostat housing. Fill until it starts coming out of the housing, and attach the back hose.
19) Attach remaining hoses.
20) Reverse steps 1-10. (Leaving coil cover off to check for leaks.)
21) Fill reservoir, and here is the procedure from the service manual, from Steve @ Tousley Ford.

According to the service manual,

Backfill the system through the heater hose off the back of the thermostat housing until coolant comes out of the fitting on the housing. Then replace the hose.

Then fill the degas tank and replace the cap, start the car, heater control to hot, A/C off, heater fan off.

Run the car at 2700 rpm for two cooling fan cycles to bleed out all remaining air.

In my experience you don't have to wait the full two fan cycles, as long as you have strong heat and the degas tank is full you should be good to go.

22) Check for leaks, once you are satisfied with it, replace coil cover, and take it for a test drive.





 
#3 ·
Thanks for the write up on this... I can't see the pics (maybe it's my work computer, will check again when I get home). This upgraded thermostat housing, is it metal? or plastic again? I've crossed 110K miles so starting to replace EVERYTHING a little at a time....
 
#4 ·
It is still plastic, but seems to be made better. It's biggest benefit is having everything machine threaded, temp sensor, plug, and thermostat cap bolts. It's a HUGE improvement. I think the only aluminum one I have found would be from HTP, and they are quite pricey.

I will try and repost the pics, I think it was my bad on that one. There are only three, and not extremely detailed, basically before, off, and after..LOL I got to working, and forgot to take all the pics I should have.
 
#5 ·
Where do I get this upgraded housing? Is it a Ford part or aftermarket? Part number? Price? Thanks in advance
 
#7 ·
Steve put the kit together, it is a Contour thermostat housing, and he includes everything you need in the kit except for the brass plug you will need for the extra sensor hole. I picked mine up at Lowe's.

CFM sells one as well, but theirs is pricier and from what Steve told me they got the idea from him.
 
#6 ·
Call Steve at Tousley Ford, he puts a nice kit together for around $120 I think
I don't have my receipt handy. I am very glad I did it.
 
#8 · (Edited)
JBotone - Thanks for the how-to guide! Could you please edit step 16 to say a 19mm or 3/4" wrench will fit the sensor, since 3/4" is within a hairs width of 19mm. I don't own a 19mm wrench, but I do have a 3/4" wrench and remembered from various past encounters with 19mm nuts and bolts that my 3/4" wrench fits nice and snug. Thankfully, I remembered this before buying a wrench I didn't actually need. By the way, I have my Tousley receipt in front of me and I paid $104.15 + $10 shipping ($114.15 total). Also, be sure to mention special internet pricing if you order by phone. The brass plug should be 1/8 inch pipe thread. When I brought my housing into the hardware store, the 1/8 inch would only thread in 2-3 turns by hand before tightening up. However, once you get the Teflon tape on it, it will turn smoother into the extra port. Also, I found a counter sunk 1/8 inch pipe thread brass plug that IMO looks and works the best. The plug is just over 7mm tall and fills the extra port neatly without sticking out. I will also list the part numbers as a convenience to anyone checking out this thread.

F8RZ 8592 AG - Thermostat Housing
F5RZ 8592 A - Thermostat Cap
F8CZ 12A648 B - Sender Assembly
W500015 S309 - Screw [:)][:)][:)](requires 3 of these)
W700319 S300 - Thermostat O-ring
F8RZ 8575 CA - Thermostat
 
#9 ·
JBotone - Thanks for the how-to guide! Could you please edit step 16 to say a 19mm or 3/4" wrench will fit the sensor, since 3/4" is within a hairs width of 19mm. I don't own a 19mm wrench, but I do have a 3/4" wrench and remembered from various past encounters with 19mm nuts and bolts that my 3/4" wrench fits nice and snug. Thankfully, I remembered this before buying a wrench I didn't actually need. By the way, I have my Tousley receipt in front of me and I paid $104.15 + $10 shipping ($114.15 total). By the way, be sure to mention special internet pricing if you order by phone. Also, the brass plug should be 1/8 inch pipe thread. When I brought my housing into the hardware store, the 1/8 inch would only thread in 2-3 turns by hand before tightening up. However, once you get the Teflon tape on it, it will turn smoother into the extra port. Also, I found a counter sunk 1/8 inch pipe thread brass plug that IMO looks and works the best. The plug is just over 7mm tall and fills the extra port neatly without sticking out. I will also list the part numbers as a convenience to anyone checking out this thread.

F8RZ 8592 AG - Thermostat Housing
F5RZ 8592 A - Thermostat Cap
F8CZ 12A648 B - Sender Assembly
W500015 S309 - Screw [:)][:)][:)](requires 3 of these)
W700319 S300 - Thermostat O-ring
F8RZ 8575 CA - Thermostat
Thanks for posting the part #'s and the price. I couldn't find a counter sunk plug the day I looked, but that would work very well too.

You can get away with the 3/4 on the sensor because it's not torqued down very tight. If you use one a 3/4 socket on the lug nuts or something torqued down a little tighter it could round off the bolt or nut. I always go with the correct size, but my OCD won't let me do anything else. :)
 
#10 ·
Haha, yeah my OCD restricts me on a lot of things, too. However, I have an adjustable wrench with metric on one side and standard on the other. When I set the metric side to exactly 19mm the standard side says exactly 3/4 inch. So of the few intersections between metric and standard, I believe this to be one of them.
 
#12 ·
OK so I got my upgraded housing kit from Tousley the other week, put it on and everything went very well. Last week I was cleaning the throttle body and noticed coolant on top of the housing where the temperature sensor screws in. When I went to remove the sensor (which I put teflon tape on when installed), it snapped off (pictures attached). I assumed it was a faulty sensor (bad quality, whatever), so I bought a new one obviously. Got everything put back together this last weekend (did the valve cover gasket as well), and after a week of driving, I checked the coolant temperature sensor while checking the oil, and sure enough there is coolant on top of the housing again. Any ideas?
 
#13 ·
#15 ·
I've been in contact with him and he suggested not using teflon tape this time. We will see how it turns out.
 
#17 ·
I did the same upgrade on my'03 and I had the same leaking issue when I first installed it, and it was because of the Teflon tape. I reinstalled it with a liquid thread sealant and it worked much better, no problems after that. One of the best peace of mind upgrades I ever did.
 
#18 ·
Thanks JBotone...I'll be doing this tomorrow.
 
#19 ·
Thanks for the write-up !! I did mine last week and it was pretty easy, I just had to fight with the hose clamps and pliers to pop them out. Also I used liquid thread sealant rather than teflon so no more leaking problem. The contour t-stat seems beefier than the oem, even the type of plastic used looks strounger.

You might want to take a look at your valve cover gasket. I've read that hot oil drippin from the top of the head onto the housing could shorten it's life. Mine was leaking so I changed it at the same time, i wouldnt have wanted to ruin the brand new t-stat.
 
#25 ·
Initially it was put in slightly tighter than finger tight...I'd hardly call that overtightened. Definitely realize that I did not need to use the teflon tape though. I was under the impression that teflon tape was just to seal threads, and did not know that it needed a decent amount of torque to work properly.
 
#27 ·
When I emailed him the other day with my issue, he advised against using teflon tape...weird.
 
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