Hello all,

I have a problem with a coolant leak in my 2004 Super V8.

To cut a long story short, I drove a good 100miles in the car and it worked perfectly, arrived back home, started the car the next morning and "Engine Coolant Low" appeared on the dashboard, the car took 2l of coolant to be full again, no puddle underneath the car, I presume it emptied itself over the motorway, when the car was running at idle there appeared to be no leak, but as soon as it revved up there was a steady stream dripping down the front of the oil pan, but I can't for the life of me work out where it is coming from, is there anything around that area that is prone to leakage, heard about the valley pipe, hoping it's not that! Any ideas?

 

As its a 2004, have you ever replaced the coolant header tank ?


These are notorious for leaking where a small pipe enters at the top-rear. The plastic nipple gradually cracks until it completely fails and the coolant can then exit in quantity. It could also be the thermostat housing. I am not sure on this one, because my car is the V6 model so a bit different, but the header tank problem is common to both. Adding 2 litres is a lot of coolant, so you have a pretty obvious leak.

 

As above on my 2003 this went as well, smelt it for weeks and could never find it, until one day of investigation I saw a small amount of dry orange coolant that had dried on its way down, gave the pipe a wiggle and to my surprise it snapped off in my hand, the coolant had eaten away at the plastic. Cheap and simple fix of new coolant tank.

 

There is nothing obvious around the expansion tank, but there is definate a stream out of the car so surely wherever it is coming from it must have a large presence, might buy/borrow an endoscope and pop it up the car and have a look.

 

Possibly hose under the supercharger. Fingers crossed it's not that one. Very tedious and expensive If you don't DIY) to replace. That's what it sounds like to me.

 

If it is the valley hose can you park the car with the nose up and see where it leaks down.

If it starts coming down at the rear of the engine then it is likely the valley hose. Not foolproof but might give you an indication.

 

its real hard to see the check holes in the water pump ,there is one on top and one under neath, however when my water pump let go it was leaking from the lower check hole and dripping from the front of the oil pan aswell . the valley pipe will always leak down the rear of the engine .

 

Thanks for all the advice!

Looking into replacing the water pump, spotted a small leak on a hose going into the engine, however it didnt drip when we started the car, so I will fix that and see if I can see any of these orange stains that are plaguing the underside of the car!

 

Valley hose leak will tend to run down the transmission tunnel, not in front of the oil pan, even with the vehicle on a flat surface, so here's to hoping you're wrong abanano