To Flush, or not To Flush?

[Odd Job]

Hi all,

Just a bit of advice please.

I have fitted an inline thermostat mod to my CDTi, as we are now heading to the colder time of the year, I intend to give my car a full coolant change.
In all the service history I have with the car I have no evidence of it being changed!
I hope it has been changed at some point since 2005!!

Anyway,
My "normal" thermostat has packed up hence the in hose thermostat being fitted.
If I use a radiator flush, do I stand a chance of the old thermostat starting to work again? If so, will this cause problems with having the in hose one fitted as well?

Many thanks in advance.

Richard

[SD1too]

Richard,

I'd say that unless you have evidence of contamination, don't bother using a flushing product, just drain and renew the antifreeze solution. Using distilled/de-ionised water rather than tap water will stop scale forming. You can pick up 5 litres for about the price of a bottle of lager in a pub. :beer2:

Simon

[ardvark]

This 'mod' you've done. Does it make the incar heater blow hotter?

[Comfortably Numb]

Richard,

I'd say that unless you have evidence of contamination, don't bother using a flushing product, just drain and renew the antifreeze solution. Using distilled/de-ionised water rather than tap water will stop scale forming. You can pick up 5 litres for about the price of a bottle of lager in a pub. :beer2:

Simon
However, if you are changing from the original specified (pink) OAT based coolant to something less (anecdotally) harmful, like blue or green silicate based, or other formula, then you should definitely flush it, as any mixing of different types causes gel-like precipitates to form.

[COLVERT]

If the old stuff comes out clean, don't flush it.