2011 C70 dumping coolant

[BlackBart]

I met some neighbors walking by while I was tinkering with my wagon on the street. They had questions about their 2011 C70 with 50,000 miles.

It is dumping coolant when they shut it off hot. They asked how hard a job it is to change a head gasket. He said there’s a crack in the overflow tank, and he’s bought a new one. To me, a 50,000 mile white block should not have head gasket problems or need a timing belt.

I said that’s definitely keeping the cooling system from holding pressure and it’s overheating. I said first step is to change that tank, check for leaks, and see if that fixes it.

But I don’t want to give them incomplete advice and overlook some underlying problem. Some questions:

1. Is a 2011 C70 a P3? P2?

2. I assume they should check or replace the thermostat and coolant temp sensor as well.

3. Is the cooling fan kicking in? Does this even matter if it can’t hold pressure?

4. What’s the story with the “octopus hose” under the intake?

5. The biggest question to me seems to be, what is the underlying cause? What cracked the tank? As simple as bad plastic or someone hit it with something? Head gasket leak pressurizing the cooling system?

Thanks for your advice -

[bskeels]

Some answers
1. C70 is a P1 car 5 cylinder turbo
2. Being a 12 year car, I would suggest the thermostat, even with the low mileage, and check or replace temp sensor
3. If the fan isn't coming on, then that could allow the coolant to expand enough to overfill the tank
4. The "octopus hose" is the upper rad hose, I can't remember where all the hoses tie in, but I remember one goes to thermostat, one might go to the oil cooler, and maybe the tank
5. Hard to say, One of my small hose fittings cracked on my tank, I had to replace my bottle.

[BlackBart]

Thank you!

He said he had a new tank ready to go on.

[Krons]

I bought a 2008 C70 in January and in first 6 months of ownership replaced all the cooling hoses, thermostat + housing and the overflow tank.

Being more than 10 years old it is good preventative maintenance. The reason is if you lose coolant while driving the position of the temp sensor can allow it to overheat before you catch it. No low coolant sensor either on the P1s so check the level at every fuel fill.