Boiling

[froggy]

Hi my S1 Xantia, just got off m50.......noticed gauge is at boiling point !!! can not see any obvious water leaks, need to wait until she is cool,,,,any ideas ? anyone one? cheers Terry.

[Stickyfinger]

What is boiling hot ? was it venting ?

[froggy]

the gauge says its boiling,,,,,,,but when I try to undo the exspansion tank,,,,there is a lot of bubbling

[Deanxm]

If its started boiling while traveling at high speed it's almost always low coolant level preventing circulation, or a blockage in the system, failed water pump, bunged up rad, failed thermostat or something else stopping water circulation.

Don't take the cap off while hot, apart from flashing to steam the coolant could boil and cause air locks.

D

[Stickyfinger]

Has the level dropped ?

and burn you badly

Don't take the cap off while hot, apart from flashing to steam the coolant could boil and cause air locks.

[wurlycorner]

Sorry to hear this, Deanxm has covered all the most likely possibles there, so no need to add anything else other than suggesting to check the oil colour on the dipstick and the oil filler cap... which you can still do while the engine is hot (if it's not like mayonnaise, your cylinder head/gasket is ok)

[Deanxm]

Sorry to hear this, Deanxm has covered all the most likely possibles there, so no need to add anything else other than suggesting to check the oil colour on the dipstick and the oil filler cap...

Is saying the words 'Head G@${€π failure' the same as actors mentioning THAT play? Do we just not say it until its confirmed

Oh and you should always open the expansion tank with a sea bass, best way to cook them IMO.

D

[Stickyfinger]

Ah the "Scottish Seal"....

Oh and you should always open the expansion tank with a sea bass, best way to cook them IMO.

I have done two steaks and a trout, some veg and a few pies % pasties on my Healey.....there is room

[Peter.N.]

I undid the filler cap of a Humber Super Snipe many years ago, it was showing hot but not boiling - until I loosened it, it took all the skin off the inside of my left arm, I had to go to hospital for weeks and it didn't half hurt.

Peter

[Deanxm]

You didn't do it a second time then Peter?

D

[qprdude]

I undid the filler cap of a Humber Super Snipe many years ago, it was showing hot but not boiling - until I loosened it, it took all the skin off the inside of my left arm, I had to go to hospital for weeks and it didn't half hurt.

Peter

But it was a lovely car Peter! Couldn't afford to run one these days though.

[darbuck]

it could be a rad fan switch gone causing the fan to not kick in however at motorway speeds it should be cooling by air flow rather than relying on the fan but if its bubbling and a lot of pressure in the tank its probably head gasket territory ive had three head gaskets on diferent cars and all done what your describing keep driving it with a bad gasket and you will get a nice oil covered windscreen.look for a water leak under the timing belt cover to rule out water pump, the best method is to weight some news paper under it.check coolant level make sure the fan is cutting in at correct intervals, if not, the sensor actually on the engine needs to be replaced they're about 15 yoyos or 10 pounds from a factors.elring multi layer gaskets are about fifty euro the bolts are usually reusable ive found it to not be too bad of a job,or not as bad as is usually made out but i recommend a re- skim at a good precision engineering place. if your in ireland and near enfield i recommend westward engineering.it could as other lads have pointed out be just the thermostat stuck closed.start there with parts replacement and diagnosis.im not scare mungering by the way just giving a line of inquiry as such.

[CitroJim]

Easiest way to check for the Head gasket is to start the engine from cold with the expansion tank cap off and then look for streams of small bubbles whilst revving the engine.

Then, whist still cold, pop the cap back on and whilst revvuing the engine, see if the top hose goes very hard very soon. If it does it denotes that compressed air from a leaky gasket is pressurising the cooling system..

[Peter.N.]

I undid the filler cap of a Humber Super Snipe many years ago, it was showing hot but not boiling - until I loosened it, it took all the skin off the inside of my left arm, I had to go to hospital for weeks and it didn't half hurt.

Peter

But it was a lovely car Peter! Couldn't afford to run one these days though.

They were a lovely car but I certainly couldn't afford to run one now. I had two, the first was a late '50s with the 2.6 engine and a Stromberg carburettor and that could manage 27mpg on a long run, then I had a 1960 3 litre with an ordinary Zenith carb, that did 16mpg!! lovely car though, had picnic tables in the back.

My wife worked for a Rootes garage in Sevenoaks so we got them at a very reasonable price. We had a Hawk first, very cheap, it had seat covers so I thought the seats were shot, when I took them off there was virtually new red leather underneath - they don't make them like that any more.

Dean

No, I've never done it since.

Peter

[Old-Guy]

If its started boiling while traveling at high speed it's almost always low coolant level preventing circulation, or a blockage in the system, failed water pump, bunged up rad, failed thermostat or something else stopping water circulation.

Don't take the cap off while hot, apart from flashing to steam the coolant could boil and cause air locks.

D

Been there with several cars over the last 45 years. In my experience, the most common cause (after a slack/failing fan-belt, which doesn't apply to Xantias!) is a failing/failed thermostat - I've lost count of the number I've replaced in various cars over the years. I've had to replace the Green lady's twice - within a couple of weeks of buying her when she started to get hot and bothered on our first fast motorway trip in her, the second time about 5 years later after similar, but less severe circumstances.

The thermostat needs changing at the same time as the cambelt - a minor addition and, like the water-pump, avoids all the inconvenience and expense of failure in the near future.