RX400H cooling fan overuse

[Adrian Parkin]

Hi all. I have owned my RX400H  for a couple of years, trouble free, during which time it has had a full service, timing belt and water pump change. I have covered around 25 k miles, bringing it to around 125k total. Until 3 months ago, I had never heard the electric cooling fan cut in. When it did, I needed to add a little coolant (about half a pint) and all was fine. However, incidences have slowly increased, and small amounts of coolant needed. There are no puddles, no obvious wet patches or drips, and the temp gauge does not alter, but the fan is kicking in more and more frequently. Any ideas?

[Hadrian]

Debris in radiator fins maybe ?, it has been rather hot recently too.

 

[Adrian Parkin]

That's a good thought......interesting access though! .......i will check, thanks

[Herbie]

I'd pressure test the cooling system. There may be no puddles because the coolant is dripping onto hot parts and evaporating quickly.

The fans are probably coming on more often and working harder (hence you're noticing them more) because of the hot weather we've been having but it's the fact that the coolant needs topping up that's more worrying.

[Adrian Parkin]

Thanks, trouble is, moving to rural Wales, not too many mechanics seem keen to work on it....they are wary of the electrics!