Thermostat DIY

[peedman]

Well this is my first DIY page and boy was it a pain. You require a new thermostat if either, your car takes long to warm up and cools down on the open highway, or your car overheats due to a thermostat stuck open. Changing the thermostat requires:

-thermostat
-thermostat o-ring
-10mm socket
-13mm socket
-16mm socket
-13mm spanner
-pliers or a hose clamp pliers
-G12+ coolant
-distilled water
-patience, cursing and frustration


Start off by jacking the front end of the car and putting it up on jackstands. Then remove the splash guard that sits near the drivers side wheel well, it covers the pulleys and belts (didnt grab a pic of it).

VW decided to make things tough and put the thermostat right at the water pump rather than at the top radiator hose. As such the powersteering pump needs to be swung out of the way to access the thermostat housing. You dont need to take the pump off but the powersteering v-belt will have to come off.

The v-belt is simple to remove. Loosen three bolts and you can use a 22mm spanner to move the adjuster so that the power steering pump moves up and slakens the belt.


So looking from the drivers side well towards the passengers side its the bolt on the right, loosen that one (theres no need to remove).


Then theres the bolt on the bottom end. Once again loosen but dont remove.


Then finally the adjustor bolt at the end of the pulleys. Loosen again, you'll remove it later on. Then move the adjustor cog to the left/top:


After that you can see the v-belt gradually being slackened as u move the adjustor cog and then the v-belt can be removed. The task now is to detach the powersteering pump bracket from the block. Its three bolts again and they need to be removed. Start off with the one on the side of the pulleys then undo the bottom ones.

Bottom two:

[peedman]

Side one, the one on the left:



Once these bolts are removed the pump can be swung away and u can see the housing. Its held by two 10mm bolts and u can remove them.

Out of the way:


Housing:


I find that its easier to wait until after the housing is loose to drain all the coolant. The bottom radiator hose is an ass to remove and the worst is trying to reattach the connection to the bottom outlet. The clips are a bugger to remove too since they are always in the worst position. I bought the remove hose clamp pliers which makes it much easier, if ur in the area u can borrow it off me if need be!!!

Thermostat out:


If the thermostat is hard to get out, just use a screwdriver and pry it out since u wont be needing it . To put everything back in is the reverse. DO NOT FORGET TO PUT A NEW O-RING IN!

Before u put the thermo back in i'd flush the system with some distilled water now.

[peedman]

Old stuff:




New:

[peedman]

After everything is back in fill with new coolant and run the engine for a bit. Turn the heater on full heat and gently massage the top radiator hose to help any air escape. It also helps doing it on a slope and thats that!.

I never want to do that again, i stuffed up the first time by not putting an o-ring on the thermostat housing-->plastic pipe bit which goes to the bottom radiator hose. I almost cried when i discovered my mistake and had to do it again! Oh well, at least it was a great learning curve. Sorry the pics are hopeless but if u want better ones ill go take em later on.

Comments are welcome!

[MattyT]

Thank you for your great walk through!

You have convinced me never to attempt any DIY mechanic stuff on my car. For this, I am grateful!

(No really!!)

[peedman]

Nah it wasnt too bad, amazingly second time around it was a breeze And you vr6 b...ards get it easy, i think ur thermostat only requires removing the coilpack or something? But definately not as challenging as the 2.0L engine.

But yeah that remote hose clamp tool is the best thing ever! Those heater clips are in such a way that using pliers would be impossible.

[gtimk5]

Fantastic write up Peedman. Thanks for that.
Getting the thermostat, O ring ans the cover on is a bit tricky, eh????
A lot of work to replace compared to a Mk1 Golf.
Hope it remains trouble free.
Andrew

[cOS]

nice write up man. good stuff.

[peedman]

Thanks for the comments guys. And yeah the o-ring doesnt hold up the thermostat it just falls out so i had to stick it in the cover upside down and push it up that way and hope the thing doesnt move.

The worst thing is the bottom radiator hose. Removing that is like missionimpossible4 and putting it back on is like lifting an elephant. Needless to say ive got big arms

[Pullstarter]

Nice write up Peed, where did you get your bits from? Think I may need a reservoir bottle myself