Coolant Overflowing

[Jon Green]

Hi all,

 

I've got a problem with the other half's car. It's a Rover 420 turbo diesel.

 

The problem is that it's chucking vast amounts of water out of the header tank partially when it is revving. It does it regardless of temperature too.

 

I have an idea that the head gasket has gone and is allowing the exhaust to pressurise the coolant, causing it to be ejected.

 

Can any of you brainy folk give me any pointers or suggestions?

 

Cheers

 

Jon

[Guest robinj66]

Unless there is a physical blockage in the pipes, I think you have made the correct diagnosis.

[Guest chris brown]

I have an idea that the head gasket has gone

I suspect you have got it in one. Sorry but it's time to get stripping.

[Guest Al Douglas]

Yep, sounds like it. I would say that unless you are going to do the work yourself it might be an idea to source a secondhand engine from a breaker. These engines as a rule were pretty robust and tended to be still ok when the body/chassis died!

Good luck.

Al.

[ibrooks]

I'd lay odds on the head gasket having gone between a piston and the coolant jacket.

 

You can get a gadget that you put on the header tank which draws air through a solution which changes colour if exhaust gases are present only I'm not sure if the solution would react to diesel exhaust. Maybe there's a different solution to put in there for diesels. Most garages should have one of these.

 

Failing that a leakdown test would help diagnose it but less garages seem to have this kit and it'd have to have a slightly exotic adapter for a diesel. You screw an air-fitting into the spark-plug hole and with the engine in position such that both valves on that cylinder are closed you pressurise the cylinder. If there's a problem air will escape and you can tell by ear where from. If it's getting past the cylinder you'll hear hissing from under the oil-filler-cap or the dipstick tube. If it's getting past a valve you'll hear hissing at the tailpipe for an exhaust valve or the carb/throttle-body for an intake valve. Or in your case maybe you'll see bubbles in the coolant. Of course in a diesel you'd have to screw the airline into a glow-plug hole so a more special adapter might be needed.

 

Iain