Installing thermostat in 2007 Vantage V8

[jerhofer]

Earlier this week I drove my 2007 Vantage V8 with the ambient temperature at around 40 degrees. Because I have been aware that the thermostat can fail causing the car to be unable to reach operating temperature, I was watching the gauge. It only came up to about halfway to the middle reading on the temp gauge. I knew I had a problem. During warm temperatures, the car reached a normal reading so I had not suspected anything.

Time to replace the thermostat. After doing some research, I found that the trick thermostat was for a Ford truck. Not too surprising since Ford owned Aston when my car was built. I found one on eBay for $24.99, part number RT1163. The seal was procured from our local Aston dealer for $16.99.








I found Red Pants instructions online which were spot on. The only reason I am writing this up is that I have documented the procedure with a number of photos and there might be interest in how I compressed the springs to install the new thermostat.

First up I put the car on my lift and then removed the front pan. With that done, I placed a wash tub under the car to catch the anti-freeze. This was only partly successful as I did not have it placed far enough to the rear.








As per Red Pants instructions I put a large trash bag underneath the thermostat housing with a towel stuffed in above that to hopefully catch the some of the anti-freeze and to keep it off of the serpentine belt.








I disconnected the long L-shaped quick-release plastic tube where it goes into the intake tube. You only need to disconnect that one end, allowing it to move around as you work. To keep it out of the way, I used a zip tie to attach it to the cross bar.







Next I disconnected the quick-release plastic tube that goes from the PCV to the intake manifold that is shaped like a 7.






I used a pliers to get the hose clamp loose from the air-oil separator, and then I pulled the U-shaped hose aside.







The next step is removing the PCV by removing the two black bolts with an 8mm socket. With the bolts out, pull straight up to remove the PCV. There are two O-rings on the bottom outlet.







Now we can remove the air-oil separator (AOS). It is a slightly smaller version of the PCV and sits below the PCV. It is held in place by one 8mm bolt. With the bolt removed, pull it out and move it to the side with the hose still attached.






Next the bracket that sits above the thermostat housing needs to be removed. There are two 10mm nuts on the side and one 10mm bolt to the left as you look at it from the front of the car. The stud next to the head makes for a tight fit but I was able to remove the bracket. I had a hard time getting the nut off on the stud next to the head as someone had rounded off one of the corners. That means the thermostat had been replaced at least once. A new nut replaced it.







Now the thermostat housing can be removed. The two 13mm studs at the top have to be removed as well as an 8mm bolt that is on the bottom directly in the middle of the housing. I couldn't get my hand on that bolt so I used an extension and 8mm socket. To make sure the bolt stuck to my socket, I placed a small bit of strip caulk on the socket. This also held the bolt in place when I re-installed it.
















As I was loosening the stud next to the head, it rubbed against the head when loosened all the way. It was actually in a little bit of a bind. To make it easier to re-install, I used my grinder to grind off some of the end.



With all of the bolts removed, I could remove the thermostat housing. What I found confirmed what I suspected. The rubber seal had torn away from the thermostat and was wrapped around the spring. It looked exactly like the one on Red Pants video. To remove the thermostat from the housing, you must push down on the spring while turning the locking pins to release them. It wasn't easy but it was doable.










The Ford thermostat is supposed to be an improvement over the original one. In the photo below you can see the difference in how the rubber is attached to the thermostat. Also, the pin is integrated into the new thermostat while the old one used a separate pin.




Before re-assembling the thermostat I replaced the housing seal.



Installing the new thermostat in the housing uses the same basic procedure as removing it. Except that now you have fresh springs with more resistance. I struggled for a bit trying to push down with my palm far enough to engage the clips while also trying to turn it. I wasn't having much luck. There must be a better way. I scrounged around in my specialty tool drawer to see what I had that might work. I came up with this three pronged puller. To keep the center stud from entering the thermostat, I found a washer and used some more of the strip caulk to keep it in place. I placed the three prongs under the housing and used a ratchet wrench to tighten down the center stud. Eventually, I had the spring compressed enough where I used a screw driver to rotate the clips into place.












It worked great. From this point, you reverse the above steps to put everything back together. Don't forget to top off the coolant. Once I had it all buttoned up, I started the car and let it run in the garage to check for leaks. I then took a little ride and the temp came up to the normal range. It was 71 degrees here today so I couldn't test for cold weather driving. With winter around the corner, I am sure there will be ample opportunities for that test.

[davidexige]

Great write-up, I'll file that one away for when I need to do mine. Thanks.

[shinjuku]

Great write up indeed.

Mine needs replacing too, but I don't have access to a ramp.... hmm...

[sundayjumper]

You don't need a ramp. I did mine a couple of months ago on the driveway.

The seal on mine was coming away:



I've read a few descriptions of this job, but none IIRC showed where the drain plug is. Mine has one here:

Edited by sundayjumper on Sunday 19th November 20:22

[jerhofer]

sundayjumper said:

I've read a few descriptions of this job, but none IIRC showed where the drain plug is. Mine has one here:

Edited by sundayjumper on Sunday 19th November 20:22

On Red Pants video, he says you don't need to bother with draining the system, unless you feel the need to change out the coolant. There is some discharge when you remove the thermostat housing. While the amount appears to be great, I did not have to add very much coolant to top off the system after completing the installation.

[Shinjuku79]

Thanks. Very comprehensive.

In the original paras you say half way to the middle. Do you mean a quarter of the way up from the bottom or half way up (the middle of the gauge).

I'm not sure whether my thermo is in good shape. I think it is but would be useful to know

- where on the gauge is normal based on per cent measurement from stone cold. So middle is 50, where you'd never want to see temp gauge is 100 and cold start is 0
- how long should it take to get there when temps are 40 Deg f or 5 deg c if driving around normally with airflow to the engine bay
- assume the valve will open and close as temps cycle. Where abouts should gauge drop to before going back up to normal. Or once temp is reached should gauge stay pretty static with minimal movement.

Thanks
Shinjuku

[sundayjumper]

Mine stays dead centre now, i.e. horizontal, pointing to the left. Like this:



(not my pic, pinched from the internnet)

With the dodgy 'stat it only got to about 25% when cruising on the motorway if the air was cool, then went up to 50% in slow traffic.

[telum01]

I've done thermostats with coolant drained and undrained, and the mess made by draining does very little to reduce the mess made when opening up the thermostat housing. If you want to drain a ton of coolant, you might as well just change the coolant with the thermostat.

[Shinjuku79]

Mine may be goosed. If I wanted to have the coolant changed at the same time what are the locations of the coolant system bleed valves (to avoid airlocks)

Shinjuku

[jerhofer]

sundayjumper said:

Mine stays dead centre now, i.e. horizontal, pointing to the left. Like this:



(not my pic, pinched from the internnet)

With the dodgy 'stat it only got to about 25% when cruising on the motorway if the air was cool, then went up to 50% in slow traffic.

My temp gauge read exactly as yours did (about 1/4) when cruising in cool weather. That was what tipped me off that I had a problem. During this summer when temps were high here in North Carolina, the temp always reached the center like it should so I didn't realize there was an issue. While I certainly would have been happy if there had not been an issue with the thermostat, because of the work involved, I was actually happy to see it was defective. Hate to do all the work for nothing.

[Ant.]

For those that have done this, how much coolant is lost by opening the stat housing?

Just trying to judge how much OAT to get hold of.

[rocketboots999]

Great write-up; thank you.

[Oilman66]

I have just joined the ranks of Australian AM owners with a 2008 V8 Vantage. Not something I ever thought I would achieve but so far all good. The car seems to be in very good cond and I have only had to do a few very small jobs such as glueing back the door seals that had come away and replacing a door strut. It also looks like I need to replace the thermostat and I have noted the Jag thermostat part number and the procedure, but also wondered if a Jag (or other make) have a suitable seal to save me the difficulty (and cost) of obtaining an AM one downunder?

[QuantumV8]

I just replaced the failed thermostat in my 2010 V8 Vantage with the Motorcraft RT-1163 stat.
My old seal appeared fine, but I'd bought a seal from the dealer just in case, so I replaced it.

I'd be willing to bet the seal is the same as Motorcraft RTS-1079, which may also be part 2W9Z8590AB, and AJ83525.
Though I don't think I'd have been able to get the seal any cheaper than the dealer price locally, except possibly from an independent.

I had to grind the stud when I had it out. I could only wiggle the bracket off past the head after over-tightening the stud to clear an extra few thou. I took 1-2 mm off it, should've taken a bit more.

Edited by QuantumV8 on Thursday 1st August 09:14

[MrBassman]

I am half-way through replacing the Thermostat on a 2008 V8 Vantage and and forgot to note how the 4 components of the Thermostat fitted together!
It looks as if the pin in the valve should be facing away from the springs - is this correct?
Also at the same time I shall replace all the coolant. Any tips on how to remove most/all of the existing coolant?

[voodoocat]

Hello, I recently replaced the thermostat. I was dreading to fight the 2 springs that hold thermostat in housing. Old one is easier to remove because they've been heat cycled so many times. I've considered to reuse it but that's not wise. Instead of fighting it, I created a DIY spring compressor with zip ties. Please see image, it's self explanatory. Don't nick the spring when cutting the zip tie. Despite thermostat being higher than radiator, you will lose about a gallon of coolant.