Hi all, I have last week replaced the coolant expansion tank without any hitches. The car was then standing with full complement of coolant for a week but having driven for four hours yesterday, it has lost all but an about an inch from the bottom of the tank. There is no sign of any leakage around the tank itself or anywhere else I can see. Any thoughts on where I should be looking?

Thanks in advance.

Can you see any coolant in the "vee" of the engine, I have found coolant pooling at the back of the engine, in my case the multiple connector (LR005819) has split and is losing masses of coolant, a right to get to.

What engine ? .
Experience is the only genuine knowledge, but as time passes, I have forgotten more than I can remember
Volvo V70 P2 2006 2.4 Petrol 170bhp Estate SE
MG Midget Mk1 1962

Previous: L322 Range Rover TDV8 3.6 2008; L322 Range Rover TD6 3.0 2002; P38A Range Rover V8 1999

3.6 TDV8, 86k miles, I must have dislodged something when I replaced the seals in the oil filter housing/fuel cooler/crank breather block. the plastic multi hose connector has split along the seam, can't see it but when squeezed with pliers there is fluid coning out of the seam. All the coolant was pooling at the back of the engine and running down the bell housing, the front was bone dry.
New one on order, then for reconnecting everything...

Mine is the 2011 TDV8 4.4 diesel. I can find no trace of any coolant anywhere, including in the V of the engine. I drove it back the other way for 4 hours last night after topping g up the coolant, and it is still full now after standing still for 24 hours, so I am wondering if it was just an air lock in the pipes from when I replaced the bottle?

When you replaced the header bottle, did you lose much coolant? It is possible that you introduced an air lock in the system and the recent drive has allowed that air to find the header tank. If there are no signs of a coolant leak, I'd be incined to top up the level correctly and then road test to get up to operating temperature then check level again.

Thanks Howard, drove it home for four hours yesterday after topping up and did t lose any more coolant, so I am figuring it was the air lock. Fingers crossed!