Radiator losing water - Emily
Hi everyone,

I drive an F-reg Vauxhall Astra, which causes me no end of grief, being an old car and all. I threw a piston last year, so had the engine replaced with a G-reg 1.4 Cavalier engine.
My radiator is 3 years old, and I've already had the water pump replaced this year when it packed up in October.
So now you know the history, here's the problem: after driving the 30 mins or so to work each morning, I've noticed a lot of steam coming up from under my bonnet. When I opened it to check, I noticed the radiator was really really low on water, but there are no visible signs of leaking. My grandfather tightened up all the hoses/leads etc around the radiator, and there's no visible puddles of water around the car when it's stationary. It only seems to lose a lot of water when I'm driving, so I have to continually top it up. I have no idea what the problem is, can anyone help?
Thank!
Emily
Radiator losing water - M.M
Emily,

Possibly the most likely problems given your description are a faulty (sticking closed) thermostat or head gasket failure.

In the first the coolant is being prevented from reaching the radiator so the car boils as it gets hot.

With the head gasket possibility the water is leaking into the engine or the engine pressure is forcing its way into the cooling system.

Also you could still have a simple leak that only dumps a lot of water while driving (so you don't notice)and then there is almost no evidence when you stop.

It is possible to help you through a diagnosis here...who would be your repairer? Friend, self or garage??

MM
Radiator losing water - Emily
Ah...yeah, someone suggested gasket problems, I'm hoping and praying it's not that!!
The guy who changed my engine last year lives just around the corner from my home home (I work near London and so live up nearer to where I work, I go home at weekends usually). I'd probably ask him to repair it for me, so long as I can catch him - he's a decent mechanic, charges an honest wage, but he also goes off rallying and stuff so it's pot luck when I can catch him. Definitely won't be me repairing my car, that's for sure!!
I don't think it's the thermostat as my temperature gauge stays normal.
I did hit something hard on the M3 last Sunday, could that have cracked anything underneath the car?
E
Radiator losing water - M.M
E,

When you stop where under the bonnnet is the steam from exactly? And doesn't the temperature gauge rise just before this happens?

MM
Radiator losing water - Emily
The steam comes from all over, around the head gasket mostly and the air filter...
The temperature gauge doesn't move an inch, it's fine! Which is what I don't understand...

E
Radiator losing water - M.M
E

Time to see "Honest garage man" then!!

Good luck.

MM