I had my suspicions about the thermostat and my iCarsoft has now confirmed that I have a thermostat that is stuck open. Researching the change process, without removing the intake manifold and was just wondering can I avoid having to drain and fill the coolant? If I remove the water pump and thermostat how much coolant can I expect to lose?

 

Not much...

 

Perfect, thank you for confirming.

In terms of products, am I missing anything (this is my shopping list)?
30mm wrench to release tension on belt
Thermostat - https://www.design911.co.uk/p/thermo...--gts---turbo/
Intake socket - https://www.design911.co.uk/p/thermo...--gts---turbo/
Waterpump gasket - https://www.design911.co.uk/p/water-...anamera_2_2-2/
The special lubricant - https://www.design911.co.uk/parts/00004320593/

Am I missing anything?

 

If you don't want to remove a bunch of stuff to get to it, you can use low profile adapters (can't remember name) and it would give you enough clearance. Been awhile since I've done mine, but looks like you got everything. I didn't use any special lubricant, but it's really important to use a good gasket. Don't stress removing the thermostat, just use a drill or something similar to break up the gasket.

 

https://rennlist.com/forums/cayenne-...l#post17262723 #816

 

Perfect, thank you. If you do remember any tips or tricks please kindly let me know.

 

Recently replaced my thermostat, at the 85K mi mark.

While removing the water pump a kitty litter pan was used to catch the coolant.

I replaced what was lost with fresh coolant. It took about 1 gallon at first, another quart was added after driving for a week.

The challenging part is removing the old thermostat. There are numerous YouTube videos detailing how it can be done.

 

I was able to get in the tight space using these.

You Tube

go to 6:53

Also test your thermostats before installing to ensure they're working right. And loosen bolts before releasing the tension.

 

Parts finally arrived. Will do an oil change first, leave the undertrays off and then tackle this job...

 

Tip: if you want to lose as little coolant as possible, do NOT open the reservoir cap. That will keep the coolant that is in the reservoir in the res, might have a slow drip.
Once I opened the rad cap with water pump removed (for no good reason, really), about a gallon of coolant from the reservoir dumped out... It was a mess.

 

Perfect, thank you, will definitely try to avoid that. I don't have anything to vacuum fill the coolant so trying to lose as little as possible until I can purchase the required tools. Aim for this year is to get an oil change done, transfer case oil and thermostat swapped. Next year I will carry out a transmission service and front and rear diff.

 

Vacuum fill is required for a shop, where they need to finish the job and send the car out.
For a DIY'er not afraid to top off his coolant after the job, vac filler is not necessary. Fill it up by gravity and start the engine, wait for it to get up to temp and for the fans to kick on, AC off (for the thermostat to open). 10-15 min, or take for a short drive around the neighborhood. That will get majority of the air out. Let cool a little and top off the reservoir, maybe overfill it a bit. Another short drive and you should be good to go.

That's what I did, even though I have the vac filler, lol (just didn't want to clean it afterwards and was in a rush). I took it on a 30 min drive right away and got the warning that my coolant level was low - all the air escaped and reservoir got drained into the engine. Topped off the res after that and that's it. No ill effects, just keep an eye on the temp gauge and maybe bring a bottle of coolant with you on first drive.

 

So an update, I have got to this stage:



Yes, not very far I know. Waiting for my torx bit set to arrive, worried about those water pump pulley screws as they are very crusty, hopefully they won't strip. However, before I go any further, does anything HAVE to be removed before I can get the water pump out or can I work it around the hoses and wires etc? I think I read online that the coolant hose (right on the pic) needs to be removed but I'm not sure as this is a 2007 Cayenne Turbo and is a little different to most of the DIYs out there...