our 2004 discovery started leaking coolent yesterday, it is coming down the drivers side behind the engine, what is the valley seal? we had the waterpump changed in September I read somewhere to try Barr's leak tablets will cure this thanks for any help

 

Very well could be the intake gasket (aka Valley seal). It seals the coolant ports in the corners of the cylinder head.

Its best to have it diagnosed though, unless you do your own repairs. The system needs to be pressure tested and carefully scrutinized, as I have seen leaks near the front of the engine run under the intake manifold towards the back.

 

This shows the valley gasket: Valley Pan Gasket & End Seals

Here is a overview of what is needed to do head gaskets: Engine Refresh (top end) | PaulP38A.com

 

thanks for the help it is the valley gasket,the truck has 110K on it, I got a repair quote for $600 plus the parts, sounds reasonable I guess? Should I have them replace the head gasket along with the valley seal? he said about $ 400 more to replace all the top end gaskets. feedback please