Water pump cause pressurization?

[vagingit.co.uk 0]

My other halfs corrado 16v (kr) has had a couple of niggly coolant leaks, one was a hose with a slight split in it, the other being the thermostat housing. They came one after the other, and now it is losing water again, but I dont where from!

 

Its had a new head gasket within he last 10k, at a reputable vw specialist, but we cant seem to stop the coolant leaks!

 

today, the water temp light started flashing, so I pulled over, checked coolant to see it had lost a lot, so let it cool down, then filled it up, and drove on fine, no more light! I sat there with it running, and I could see that the top rad hose was bulging, and rock solid when I squeezed it, is this right?

 

It had a new thermostat when the housing was replced, but could the water pump be dying, causing the cooling system to pressurize? I think the leak is also from the water pump!

[Kevin Bacon 5]

Coolant leaks work their way round the entire system until each weak spot is fixed unfortunately.

 

Top hose sounds bad, is the bottom one cold when that happens? What's the radiator core temp like also?

 

Personally, I would change the pump, Rad, thermostat and any weak looking hoses. It's the only way to nip it in the bud permanently.

 

VAG rads tend to lose efficiency with age and can start seeping where the plastic ends meet the alloy core.

 

Replace the lot!!

[vagingit.co.uk 0]

The bottom hose isnt as hard, and is hot, so Im assuming the stat is fine, the car hasnt overheated, and the oil temp remains at a good level, its just that the hose was harder than Id have thought, I will be checking again later when it has cooled down to see if the hose has returned to its natural shape, or in fact it was just me reading too much into things.

 

the water pump makes no noises, and the rad seems to remain dry around it, I cant see any leaks/white staining!

 

Ive also put a new blur expansion tank cap on in the last 6 months as a matter of course

[Jim Bowen 1]

i think there is a stage in every corrados life when the cooling system systematically breaks down each week :lol:

 

i had thermohousing, then pipes, then the radiator, radiator was a hard one to spot though as it was only leaking when i had driven it hard

[Kevin Bacon 5]

Ive also put a new blur expansion tank cap on in the last 6 months as a matter of course

 

Is that the special one the pop band made? :D No wonder you've got air locks in the system!

 

TBH, visual inspection isn't always enough. The only way to be sure is to monitor water level and if it's defo going down, you defo have a problem, regardless of how the parts concerned look. Unfortunately coolant issues usually always turn out to be a process of elimination, hence why I suggested just going for it and replacing all of it. Then stick the old stuff on ebay :lol:

[billy_whizz 0]

i also have a 16v, pressurization in header tank, the top hose goes rock solid and you see the air jerking the top hose, and then the water comes out of the exspansion tank, no water in the oil, the rest of the engine runs fine. head gasket has been done,but didn't get head pressure tested could it be a cracked head,still the same. any ideas? help!

[Roan 0]

I also have high pressure in my VR6 cooling system. Replaced Aux Water Pump, Heater Matrix, Expansion Cap (with blue one), and Crack Pipe, as well as flushing out the system twice with non-corrosice cleaner. No sign of oil/petrol in coolant, no white smoke from exhaust and compression tests etc are all fine. Car sits at about 102 in traffic and drops to 90 on a motorway run with the top hose being very firm after a drive. No leaks but I'm wondering whether it would be prudent to change the rad and water pump?

 

I also think the yellow temp sensor and fan switch could do with replacing as the temperature readings might just be out after 150k miles and 15 years...???