If the cooling system has ever been topped up with tap water, then certainly give it a quick flush through. Only ever use distilled or 'de-ionised' water. If tap water has never been used, then you'll probably find that the old coolant is quite clean. Can you change the thermostat on its own on that engine? There's so many engines these days that use a thermostat housing with lots of pipe connectors and the thermostat built-in so that the complete (and expensive) housing has to be changed. But why change the thermostat if it's working? Leave it 'till it fails! On my car, it was the thermostat housing which failed (at 175K miles) because the rubber seal inside it had swollen and broken the plastic wall inside, so that the housing started leaking.

Check with Honda but according to book coolant change is 125k, its check and top up if you need to on services otherwise

Unless you have to, you dont need to change stat

Thank you all about the suggestion, very reassuring, i was planning it on the safe side anyway.

Also Should i get the brake fluid, clutch fluid, transmission oil ( manual ) changed ?

Thank you.

After 7 years:

# IMO coolant is slightly overdue. Most cars have 5 year coolant, but some now have 10 year. Either way, flush with clean water and run a proprietory cleaner through it. You can buy coolant ready mixed, but if you mix your own make sure to use de-ionised water.

# if the system is clean, there are no leaks and it's working fine then leave the stat alone.

# brake flud is long overdue. Most manufacturers specify between 2 and 4 years for a change. Brake fluid absorbs water vapour and oxygen through the rubber hoses and seals which lowers it's boiling point and increases it's compressibility. Water vapour in the fluid can also cause internal corrosion of the system. If your car has ABS and ESP then it's even more important to maintain the fluid. I use Shell DOT4 ESL (you can download the fluids brochure from Shells website).

# if your clutch is hydraulic, then yes change that fluid at the same time. It may be fed from the same reservoir as the brakes.

# most transmissions are "filled for life". However, "life" in this instance means 10 years or 100k expected average. If you want your car to give much more service than this I suggest a change. I change my gearbox oil every 50k. I have used Redline MTL in my GM F40 box.

# on previous cars I have changed steering fluid at 100k. If you have any reason to believe the fluid may have overheated (if it smells "burnt" then that's a defo, can happen with prolonged full lock at very low speeds) then have it changed.

Edited by Cyd{P} on 25/04/2014 at 17:17