coolant pressure problems

[Thinlysliced]

Hi All,

Can someone explain the following to me in simple terms?

 

I have recently found that the car is losing coolant and the mechanic said that high pressure in the coolant system is making the coolant come out of the pressure valve on the expansion bottle.  The coolant light comes on so I open the cap and top it up, the light goes out for a while and then we start all over again.

 

He did the pressure test on the coolant system and was fairly sure it wasn't a head gasket issue, although he did say he couldnt be one hundred percent sure.

 

The mechanic noticed that flow through the radiator was restricted and on closer inspection there was radweld and another substance whose name he gave me but I cant remember more than it had copper in the name.

 

I have therefore had a new radiator fitted. 

 

I drove it for the first time today and after about 30 motorway miles the light came on and so I topped it up a few miles of road travel later the light came on again.  This time I topped it up and the light has not returned as yet after completing the return 30 miles on the motorway.

 

There is no milky oil visible and I can't see excess water coming from the exhaust pipe.  My mechanic has been in business for around 20 years and up until now has not had to deal with a blown headgasket on the skoda block and has always considered them fairly rock solid.

 

He has also mentioned that the clutch and flywheel are due to be replaced.  So I am wondering if to get the above work done or move on.  I have only had the car a year 

 

The car is a skoda superb 2.0 tdi on a 2010 plate.

[scoop3379]

I had coolant top up issues at 60k. Research on the forum told me, water pump. I had a new water pump fitted, and not had a problem since. 

Good luck. 

[Thinlysliced]

Thanks Scoop3379.

 

The timing belt and pump was replaced about 9 months ago and has been inspected and looks ok.

 

Unfortunately, the mechanic, who is a mate is fairly sure it's a head gasket now.  That and a new clutch required as an unrelated repair.  It's going to be an expensive month.

[peterposh]

The stop start engines have an electric water pump as well , I think this comes on when the engines stops at operating temp and may overheat otherwise. I had a warning come up once that it wasn't working

[Thinlysliced]

Thanks, my car doesnt have stop start though

[Thinlysliced]

The mechanic ran the test with the air lock again and my head gasket is buggered. unless of course the block is cracked.

[peterposh]

it's buggered now it's been overheated I suspect, maybe flush out the radiator and coolant circuit to see if there's any junk in there? I assume the fan is working etc? . strangely enough after saying about the auxiliary water  pump  mine has gone faulty yesterday  fault 261A   ! Grrrrr I've booked it in next week

Edited 3 June, 2017 by peterposh