Corsa thermostat change - jim holland
I need to change the thermostat on an 8v 1.4 Corsa but it looks as though to remove the top belt cover, I have to take off the cam wheel to do it. I changed a thermostat on a Nova a couple of years ago and can't remember anything like this. The Haynes manual makes it sound a simple job - just remove it. I got as far as removing the cover screws through the cam wheel holes but nothing came off. Apart from a brain cell - what am I missing?

Corsa thermostat change - big davey
Hi, you have got to remove the crank pulley,timing covers,timing belt,cam pulley, three torx bolts keeping timing cover backing to head, which should give you access to thermostat housing. Remove hose to housing and remove the two bolts in housing. Make sure you align timing marks before removing belt. You may need to remove timing belt tensioner to let cover come over tensioner.
Good luck.
Corsa thermostat change - jim holland
Thanks Davey. Looks like my simple job is going to take a bit longer than I thought.
Corsa thermostat change - RoadDevil
I used to have a 1.6 Astra with the C16SE engine which I think is very similar to the 1.4's.

I couldn't believe how stupid this design is when I first realized what was involved in a simple thermostat change. The timing belt and pulleys indeed need to come off to be able to remove the back timing belt cover. (never understood why the thermostat wasn't located in the hose or extended so that it could be changed without becoming a major job).

If you're going to change the thermostat you should gear up for a major job (straight forward, but long winded) - a day's work for an amateur;
1. Remove air filter box (for access).
2. Remove drive belt, may well run round an engine mount, just secure out of the way unless it's worn.
3. Remove outer timing belt cover.
4. Set engine to TDC.
5. Remove crankshaft pulley.
6. Drain cooling system, remove timing belt, water pump and tensioner.
7. Remove camshaft cover and then remove camshaft pulley.
8. Remove rear timing belt cover.
9. Remove two thermostat housing bolts (finally!)
10. Flush cooling system and radiator with a hose (you may as well if you've got this far!).
11. Fit new thermostat with new seal.
12. Refit rear timing cover.
13. Refit camshaft pulley (following correct torque setting from Haynes).
14. Fit new water pump + seal and tensioner (if you've gone to all this trouble these components should be renewed).
15. Fit new timing belt checking TDC and tension as described in Haynes (you'll need a special spanner to rotate the water pump - saw one on eBay the other day for £3).
16. Refit outer timing belt cover.
17. Refit crankshaft pulley using a new bolt to torque/angle setting as in Haynes.
18. Refill cooling system with new coolant.
19. Refit air filter, etc.
20. Congratulate yourself on a hard day?s work and a large bill saved (which may well write the car off if it's a few years old.

Straight forward, but a pain in the...

Good luck.

Corsa thermostat change - Crinkly Dave
Grief. And I thought the Fiat diesel was a pig. How can anyone justify a design like this. Almost worth swopping the thermostat at every belt change
Mind you, the FIAT one is £57 plus vat
Corsa thermostat change - RoadDevil
Grief. And I thought the Fiat diesel was a pig. How
can anyone justify a design like this. Almost worth swopping the
thermostat at every belt change
Mind you, the FIAT one is £57 plus vat

That's exactly what I used to do (after the thermostat became sluggish a week after a garage charged me an arm and leg to change the belt the first time and then told me they'd have to do the whole job again to reach the thermostat!)
Corsa thermostat change - wemyss
Don't know if this is any use but years ago my wife had a Nova 1.2 and it sounds very similar.
The thermostat needed changing and the same procedure as described needed doing.
Took it to the garage down the road and the owner siad theres a much easier way. He simply eased the cambelt off the top pulley with a large screwdriver. Replaced the stat and with the pully markings set he eased the belt back on.
Perhaps the later Corsa is different but it does sound very familiar even down to the special large spanner which he didnt have to use.
A few years later I replaced the cambelt myself which entailed needing a long pipe to undo the bottom pulley to remove. But once again I was able to get the belt back on without loosening the water pump.
Corsa thermostat change - jim holland
Thanks very much guys - much appreciated. I changed the belt last September so it's that job all over again. Now I'm all geared up for Sunday.

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