Loosing water when hot

[kennatt]

with the cap off and at the correct level,fully warmed up.when you rev the engine can you see if the level of water drops slightly(as it should) as the water pump draws water through the rad.If not noticable,could indicate blockage or water pump vanes rusted out(it can happen),and therefore not shoving the water round the system fast enough to cope with hard motorway driving.

[bmcecosse]

Yes - good points there ^^^^^^.

[hanvyj]

Aha! Found the problem at last!

The leak was in the heater valve. The water ran down the back of the engine, which is why I never spotted it.

Thankfully something simple! Will probably fit one of those older tap-valves as the 1275 puts the heater valve in an awkward place.

[bmcecosse]

Well done - but surely must have been obvious on the ground?

[hanvyj]

I hadn't noticed it before today, I think it only happened when I was driving rather than at idle or revving? Not sure, but I'm sure I would have noticed it.

[bmcecosse]

Let's hope that's it sorted!