Water Is Boiling

[billy no brakes]

As the title says the water is boiling and has blown the cap off the expansion bottle, I have bled the system and there was no air coming out of the radiator bleed nut just water or both the bleed nuts on the water rails. But when it gets hot steam is coming out of the expansion cap / bottle when hot. any ideas I have been told it could be the head gaskets hope not as I have just spent a fortune on the car and have no money left due to cut backs at work, Any advice would be greatly recieved

Gary

[1Dog74]

billy no brakes said:

As the title says the water is boiling and has blown the cap off the expansion bottle, I have bled the system and there was no air coming out of the radiator bleed nut just water or both the bleed nuts on the water rails. But when it gets hot steam is coming out of the expansion cap / bottle when hot. any ideas I have been told it could be the head gaskets hope not as I have just spent a fortune on the car and have no money left due to cut backs at work, Any advice would be greatly recieved

Gary

When the coolant is cold where does it come upto on the expansion tank? the reason being is as long as there is some visible water in the expansion tank that's all you need, even when on the minimum level it can cause the cap to leak.

The other thing is replace the cap with a Geniune VW/Audi part just incase the cap is faulty.

For the record, my coolant has around an inch of visible fuild and is spot on temp wise.

Hope its just a case of an overfilled expansion tank for you.

Regards

[C3BER]

First thing head gasket would mean the false boil but you have steam so it's a boil.

Yes it can be over filled and any extra will get thrown out. And yes the caps can be faulty which will give you the boil effect.

Are the fans coming on...if not it's a simple faulty temp sensor or an iffy connection on the fans. Both are easy FUBAR fixes.

[FUBAR]

[C3BER]

FUBAR said:

I'm going to see if Oxford dictionary will have "doing a FUBAR" placed into the 2012 edition.

[billy no brakes]

C3BER said:

First thing head gasket would mean the false boil but you have steam so it's a boil.

Yes it can be over filled and any extra will get thrown out. And yes the caps can be faulty which will give you the boil effect.

Are the fans coming on...if not it's a simple faulty temp sensor or an iffy connection on the fans. Both are easy FUBAR fixes.

to start with I let the engine go cold and filled up the system with water and started up the engine, then bled the system on both radiator and water rails and filled up to the maximum line in the expansion tank and let the engine idle till it got hot thats when the cap started giving off steam and blew off also one fan came on looking from the front of the car it was the one to the right.

I contacted Paul Vincent who came with another cap and we went through the same as thing as above and the same thing happened the water was spitting out before we put the cap on and when we put the cap on steam was coming out of the cap, only one fan came on though, could it be a sensor fked or is it the head gaskets, I have looked in the oil filler cap and it is clean and also checked the dipstick 3 times and the oil on the dipstick is clear not creamy which would suggest the head gaskets has gone.

One other thing when driving it is fine but at idle the problem starts.

Any constructive ideas would be greatfully received.

Gary

[1Dog74]

billy no brakes said:

to start with I let the engine go cold and filled up the system with water and started up the engine, then bled the system on both radiator and water rails and filled up to the maximum line in the expansion tank and let the engine idle till it got hot thats when the cap started giving off steam and blew off also one fan came on looking from the front of the car it was the one to the right.

I contacted Paul Vincent who came with another cap and we went through the same as thing as above and the same thing happened the water was spitting out before we put the cap on and when we put the cap on steam was coming out of the cap, only one fan came on though, could it be a sensor fked or is it the head gaskets, I have looked in the oil filler cap and it is clean and also checked the dipstick 3 times and the oil on the dipstick is clear not creamy which would suggest the head gaskets has gone.

One other thing when driving it is fine but at idle the problem starts.

Any constructive ideas would be greatfully received.

Gary

As I said earlier, some cerbs do not like the coolant filled to the maximum line, keep it on the minimum - I reckon that will solve it - you dont appear to have any other problems other than over filling.

[ridds]

Failed stat not allowing enough flow?

Go and buy a sniff tester. It'll answer all your questions in 5 mins flat.

[ukkid35]

Same symptoms, plus a very awkward 'block leak test' lead me to the inevitable/dreaded headgasket failure diagnosis. Except when I took the heads off the fire rings looked intact. I wish I'd spent more time exploring other causes, but I didn't, I just assumed the worst.

My advice is exhaust every other possible cause before pulling the heads, because it's either very expensive or very time-consuming (and needs lots of support - emotional/financial/practical).

[C3BER]

Everything has been answered and I wish I could just pop over and show you.

I had the same problem as yours and I only dare go out if I knew I had a clear road to drive on. Stopping I would see the corner of the screen steam up followed by old faithful.

Do as Ridds says so at least your mind is at ease.....or not.

Don't fill to the plastic line but under.

Do check for cold pipework when you boil.

Take the wire off the temp sensor to get both your fans on permantly.

Don't believe the laptop as it tells little White lies regarding temps due to possible faulty sensor.


And change that fncking temp sensor.

[Ireland]

Is the stat ok?

If not then that might just be your problem.

If it's not opening it will cause the water to boil at the expansion tank.

You might need a new stat.


Has the stat already been changed?

If so is there any chance a piece of wrapping / packaging stuck inside it stopping it opening (might sound mad but it happened to me when I changed the stat in mine) ?

Also if the stat was changed has the new one been fitted the right way?

Some of the new ones physically look like the originals but they actually need to be turned differently to get them to work properly (almost happened to me).

[colin 82]

Hi

Sorry read your post and it just sounded to similar.
Brothers 4.2 was rebuilt. Literally drove 1000 miles in it.
then driving back to the garage for its first check.......the same happened.

Garage said i was nothing.......bla bla bla. drove it back home (400 miles) pulled into the drive and the boil started again.

Numerous calls to the garage.....maybe a split hose etc, fan switch etc.......BUT NO.
Put it to TVR POWER who discovered that the head had gone after a shocking re-built.

Should have put the car to them in the first place.
The un-named garage destroyed the TVR experience for my brother.
Car is now sold........Maybe one day ill get my brother a Sagaris thru Dom.

Call Dom......he will he you

[C3BER]

99% it will be something silly that causes over heating, 1% a major rebuild.

Looking forward to seeing how it pans out.

[gruffalo]

Plug a computer into the ECU and see what the temp actually is, what does the gauge read, if only one fan is coming on it is unlikely to be a damaged sender, it is more likely that it is over filled. Fans cut in at 92Deg or something like that and at that temp water will start to steam gently like a cup of teas gives off steam but is well below boiling point.

Where are you?

[billy no brakes]

Hi All

Thanks for the replies just got back from Cornwall and the weather was perfect and would have been great in Cerb what a fking pest as I was really looking forward to the a A303 never mind gald it was not on the way there or back, we are going to do a sniff test one night this week so will know if gasket has gone then if it has it could be good bye Cerb has I simply have not got the money at the moment don,t want to sell as had her 12 years now and it was going to be with for ever but we will see

Gary