300tdi slight coolant loss

[100SRV]

Hi,
I checked the fluid levels on my Defender yesterday and noticed that the coolant header tank level had dropped by about the thickness of the reference seam. It's never done this before and there are no obvious leaky hoses.

The engine is over 300,000 miles now, so I keep a close eye on levels. It still runs well, what are the likely culprits?
Water pump, P gasket, Cylinder head?

[camel_landy]

TBH - I'd just monitor it for now coz the slight movement could be caused by the rise in ambient temperature.

If it does continue to drop, I'd be looking at the usual culprits but starting with the heater matrix & radiator.

M

[anonymous-user]

In addition, look along the seam of the header tank itself for staining. Those are prone to weaping.

[100SRV]

Thank you all, the seam of the header tank is dry.
I'll check the radiator core and tank/core seams for damp patches.

[100SRV]

I added a low coolant alarm system which I found on eBay (it uses the 300TDi Range Rover filler cap/level switch) to give some peace of mind should there actually be a leak.

All seems well with coolant levels over the past 100 miles so I guess it was me being over-cautious.

[camel_landy]

Ta for the update & glad it was simply a case of mild paranoia.

M