Coolant level

[TomPaine]

I got the coolant level warning last week. I was on a very slight incline (where it had been left for several days), which made me wonder if it was nothing more than that, but when I tested it on the flat (and cold) the level was a good half an inch under that middle ridge on the reservoir, which it's normally at. I've been putting modest slugs in probably once or twice a year in the last few years but this required more than that. Thinking about it I bought the 1-litre bottle some time during Covid lockdown, and it's now down to the last maybe 25% or so. Is that standard for a 21-yr old car, ie keep an eye on it, or more ominous? (There are no symptoms, temp needle is at the same point as ever etc.)

[Audax]

Probably a leaky rad or hose rather than being too scary, realistically just keep and eye on it for now and make sure you carry about a bit of spare water and coolant and monitor it after driving.

[TomPaine]

Thanks Audax. Yes indeed, I keep a bottle in the boot for top-ups. I suspect there's a tiny weep somewhere which might be accelerating. ISTR someone saying that they asked the garage to check things in similar circumstances, whereupon they pressure tested it and converted a minor weep into a major leak, so I wonder whether it's better the devil you know at the moment ...

[Audax]

I should probably add have a very good look around the engine bay at all the hoses and check the condition of all the hose clips, water pump etc. for any sign of crusty leaks or something that might be about to fail. Just in case...

[sgould]

I got desperate a while back on the 9-3 and added some fluorescent dye.  I found the leak with an ultra violet torch.  There were a couple of misdirections when i found that there were a couple of (repaired) leaks on the aircon that had the same sort of dye added.

[carrera]

Anti freeze can create its own tell tale marks. If it's a really slow leak, it might just be a tiny pin prick in a pipe, or waek clip, that will not show as a leak because it comes out as steam, or because it only happens when the engine is hotter than normal - idling when stationary for example, before the fan kicks in