Cooling System

[lffuller]

Hi everyone

Just a quick question about the cooling system. Just had my MR2 serviced and I think the stupid garage may have topped my cooling system up with a little bit of water instead of the 'for life' stuff! Will that damage it or will it be ok? Also, when driving and having the temperature slider fully in the cold position, I notice that the air coming out of the vents is slightly warm. What would that potential problem be? Any ideas?

Thanks
Simon

[anthonyg]

Not unless you've got air con

[System-G]

I've run these cars on water only (no coolant at all), a mix of for life and water and For Life / Long Life (or Halfords brand ethylene glycol based) coolant only (not tainted with water) and have not had a problem with the cars overheating.

Only issue you will have using water only long term is a buildup of scaling and rust which could block the system leading to other faults worst case.

Topping the system up with a little water is quite perfectly fine.

What you really want to avoid though is mixing alcohol based coolant with Ethylene glycol based (long life/for life) coolant - it will turn to jelly pretty rapidly.

[BenF]

Having replaced a HG a few months back, the old coolant had corroded the block face letting coolant weep out - so IMO its definitely best to run the coolant system with Antifreeze including corrosion inhibitors in. FWIW I use the Halfords Advanced antifreeeze.

As for topping up with tap water - should be fine, assuming its a small amount (eg less than a mugfull) and you've got coolant in there that has been changed in the last few years. If you're talking about adding a litre or more, I'd mix up coolant and water to the right concentration and then add that.

[lffuller]

Thanks everyone. That puts my mind to rest.

Simon