Hi everybody, I'm a brand new member and have an issue.

I have just had a new cam-belt and water-pump fitted on a 3.0 MV6. When I collected the the vehicle the coolant warning light came on and when I checked I saw the reservoir was very low, despite the garage having put in 2l of coolant. Naturally I topped it up, however after about 15 miles it happened again. I put in 2l of coolant but after another 10 miles it happened again! I looked underneath while running the engine and saw coolant leaking out between the front wheels, slightly tothe driver's side and from quite high up. I felt that some numpty at the garage hadn't connected the water-pump correctly so took it back to them.

At the garage they did a pressure-test and ran the engine, before saying they could fine nothing wrong.They did not investigate further. Strangely, when I ran the engine myself and looked underneath, I could see no leak at all. So, I then drove the 92 milesfrom Bristol to Bagshot and all seemed okay. However the next day, after about 4 miles it started again. This time I recorded it on my phone before calling the garage, and will take it back on my return to Bristol later this week.

I am convinced that a hose has not been connected properly and that the garage are responsible but would appreciateany advice. Having just paid for the cam-belt and water-pump, as well as a new set of tyres, HT leads and the MoT a couple of weeks before that, I can do without another bill. As I say, I believe the garage are responsible as it didn't happen before they replaced the cam-belt and water-pump.

Help, anybody?

That is most likely the Heater Bypass Valve which is located at the top rear centre immediately behind and clipped to the engine block above the gearbox bellhousing.
Its vacuum operated and controlled by the climate control so will only work (and leak) when the climate control tells it to which is why the leak is not constant.
Its a very common fault, easy to replace yourself and fairly cheap too. Just make sure you get a genuine vauxhall one cos the other types I have tried do not last very long before they fail.
Yeah! watch your skin too cos you will lose a bit and there is a bit to show you how it is done in the Maintainance Guides section. Just type HBV into the search box! Here is the page link;
http://www.omegaowners.com/forum/YaBB.pl?num=1193594464
Until you get it done just disconnect the small vacuum pipe from it and block the end. You will probably have to remove the windscreen scuttle unless your hands are very small though.

Only read the first half of the first post.

Hbv.

This all seems to make sense.  Especially the bit about the Climate control affecting it. When I tried it at the garage and all seemed ok the climate control/heatimg controls wereall OFF.

Thanks everybody.   

It's possible it was jammed and disturbing the engine coolant has freed it off and exposed the leak.

Over the winter the HBV never has to do anything and mine have always let go as soon as the decent weather starts - I've not had to change one for a few years now 

Actually, while I'm here, best place to get an HBV? Vx dealer, or is there a cheaper alternative, ideally local to Bristol, or Bagshot in Surrey (I split my time)? Like I said,trying to save the pennies after all I've had done recently!

Drive Vauxhall Aldershot have been ok for me - pm me if you want to know anything further

Thanks everybody. Part ordered from Vauxhall Camberley. Collecting tomorrow and then fitting with a (hopefully patient) friend. Out of curiosity I asked the dealer what they charge to fit......wait for it....... £144 PLUS the part! Only just stopped laughing.

Thanks again all, your help has been invaluable.