guide to changing thermostat

Smoki333

Active Member
Dec 20, 2005
472
0
Wiltshire
ok sounds good.

Is it best to flush out the system first with water till it runs clear at the bottom and then do up the tap, fill it up again and put the lid on the header tank. Then idle or drive with the heater on full and then drain again and fill with coolant.

I take it this should get rid of any air etc?

yep, id flush the system till it runs clear then do the rad tap up.
Fill it doing a 50/50 mix (water/coolant) or whatever you choose...
I personally fill the coolant with a 50/50 mix till the coolant bottle is on its max marker then start the car and run it on idle with the heaters on hot so the fresh mix passes through the heater matrix, at this time i still have the coolant cap off so i can top it up if it does drop, an i squeeze the rad pipes top and bottom to release/move any trapped air.
Wait till i feel its HOT which means the stat has now opened.....
again top it up if need be and finally coolant cap back on.

On idle and with the heaters on hot will take a while for the engine to generate heat and get up to temp!

Take it for a little drive an have some fresh mix with you as its more than likely gonna need a top up :thumbup:

Sorted...Never had any issues doing it this way
 

three_cross

Active Member
Oct 14, 2011
95
0
Did this using the guide and it took about an hour and a half. The longest time was finding the tools I had that would get to that bottom bolt.

In the end I got a 10mm spanner from my neighbour that was only about 4-5cm in length and still had the fully round end aiding in small movements. Worked a treat :)
 

rizer290

Active Member
Apr 22, 2010
238
0
Northampton
all fixed guys thermostat sorted temperature gauge out, sitting at right temp at 90 degrees. Quite an easy job just remember to drain all coolant, and it helps using a magnetic spanner, takes less than an hour.
 

offitmassive

Guest
Did this using the guide and it took about an hour and a half. The longest time was finding the tools I had that would get to that bottom bolt.

In the end I got a 10mm spanner from my neighbour that was only about 4-5cm in length and still had the fully round end aiding in small movements. Worked a treat :)

yeh bottom 10mm bolt is a bit of a job, i tried and tried with all extensions on my ratchet, arm was scratched a treat, so tried a single depth 10mm socket on my 1/4" ratchet, and it worked...
 

ScoobyJawa

Achtung!
Oct 2, 2002
449
0
Liphook
Visit site
Just to add to this as I did it today, once you have the right tools its easy! IMHO the 3/8" Universal Joint is essential to do this yourself, costs about a fiver in Halfords. And the extension bars are needed almost as much.

Just to aid anyone else looking to do this.
 

Malice19

.:Cupra 4 The Win:.
Mar 16, 2006
519
0
Swindon
Hi I have changed the temp censer and the problem has come back so advised that it must be the thermostat.

I have a new thermostat ready to fit as feel like giving it a go as the temp censor was so easy to fit but can not seem to find as good a guide as i did for the temp censor...

Have looked at the link on this thread but as im a noob i need pictures, can see at the end of the TT forum thread that people were asking for a copy as pics have gone?

Do you have or know of any one with this guide with Pics on how to change the thermostat?

Cheers
 

Malice19

.:Cupra 4 The Win:.
Mar 16, 2006
519
0
Swindon
As i see a few people have been having this problem i thought i would upload some Pics to help peeps get a better idea how to get to the thermostat...;)

I have read that people have managed to change the thermostat without disconnecting the tensioner and the alternator but found its so tight and much easier to get to the thermostat by taking off the 3 bolts off the tensioner and removing it then taking the 2 bolts out the alternator and moving the alternator over to the left to have nice clear access to the thermostat.

Alternator was a bit rusty where the bolts were so a bugger to get off, so had to use a large flat head screw driver to leaver it off :D

(I am just a poor noob and just posting the pics in the hope it could help other noobs what to look for :bleh:)

3 Bolts off the tensioner


2 bolts off alternator



Moved Alternator over to the left to expose thermostat.

 
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Malice19

.:Cupra 4 The Win:.
Mar 16, 2006
519
0
Swindon
Dam what a long day, managed to sort it thank god but was not much fun in the cold and rain today :(
Longest part was trying to get the dam alternator back on by lining up the 2 holes as was so stiff. Then it took me a while to figure out how to put the belt back on as did not make a good mental note of it :p

But it was all worth it as now showing correct temp just over 90 and rock solid :D
What the next rank/step up from Noob...??? Amateur spanner monkey? :rolleyes:
 

adam cupra 20vt

Built Not Bought.
Mar 31, 2005
6,162
2
Mud Hut
No need to remove alternator. I've done 3 now you just need a small ratchet with a flexi joint, it's quite tricky but not impossible.
 

TheMadHatter76

Active Member
Apr 5, 2011
25
0
Leicester, UK
Great instructions here but I don't have the right tools so I took it into a local garage. As well as changing the thermostat (which I provided), they also replaced the coolant, except they didn't use G12, just the standard coolant. They must have wondered what the pink stuff was when they drained it. Aside from this, there's a thermal flap (excuse my terminology...) hanging over the engine where they've obviously not put it back properly. Monkeys is the only word I can think of to describe those mechanics. The blowers are also making a whistling noise now and there was a LOT of condensation on the front windscreen that took a while to clear (to be fair, it's really cold today but I've never had condensation like that before). On top of that they charged me for two hours labour for what sounds like a 30 min job. The funniest thing was when I was explaining it and there was a woman dressed all smartly shaking her head when I tried to explain that it's an hour's job maximum. Perhaps she was the owner but she didn't look like the mechanic type. Ah well, you live and learn.

Anyway, I've taken the car back and informed them that it requires G12 and not the normal coolant. They asked me to leave it with them. From reading about, it's quite important that it has G12 in it for longevity. It states G12 on the bloody bottle as well, so I'm assuming they either ignored this or they simply can't read. I was polite about it and I'll be picking the car up tomorrow. Do you think I'm in the right to ask them to swap it over for free, just in case they try to charge me? I'm assuming it's the garage's responsibility to ensure the correct liquids (and parts) are used?

Thanks :)
 
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