Omega v6 Bad Water leak

Hi folks,
My 98 S Omega has developed a bad water leak. But I cant see where it is
coming from.Its dripping large puddles of water from the back of the engine
next to the bulk head. I have to top it up every day. I suspect its the
known porous oil cooler problem. If so how much should this job cost in a
main dealer or good independant garage and how much is the unit itself.
Theres obviously a lot of labour involved to get at it.
Thanks in advance for your advice,
regards,
Michael.

 

it may well not be the oil cooler. mine had a similar problem 18 months ago.
there is some water pipework behind the engine that has a plastic manifold
where they all connect. this is a known problem with v6 omegas. can't
remember what it cost me to have done though

 

There is a plastic valve for the heating/air con in the pipe work at the
back of the engine.
Follow the heater pipes out from the bulkhead to the engine and you will see
it. Black plastis with 3 rubber pipes to it. They are always leaking. DIY
job if you don't mind getting wet.