Head Gasket ?

[J1MBO/m]

the dye sounds like a good idea I will have a look for that ......

[J1MBO/m]

ok thanks will do ....

[Adrian]

I've never yet run out of coolant in one, but they definitely seem to leak.

[Dave Liquorice]

I thought the dye they used in the now permenantly used antifreeze/anticorrosion stuff was flourescent? Either way it ought to be possible to find the coloured residue from it near the leak. But the colour of the residue may not be the same as the coolant, pretty sure the pink coolant in my car leaves a green residue.

The biggest problem with modern cars are all the damn covers and auxillary kit that is shoehorned into the engine bay meaning being able to see the actual engine might be quite tricky. Might not be a problem with a Ford V6 though.

[Brian-Gaff]

Steam? Brian

[CB]

Once up to normal temperature, just shut it off, lift the bonnet and look/listen. Temperature and pressure in the cooling system increases in the 3 or 4 minutes after shutdown as the heat soaks out of the block into the coolant. This may be enough to force the leak and the lack of engine noise and pulley movement may enable you to hear boiling off of minor leaks or see small wisps of steam.

[gareth]

Had to google for that one; has the supercilious mason sneered about his imagined superiority once too often?

[Bob Minchin]

It goes into the cylinder and expelled as steam. It should be giving you better mpg/more power too. I used to run an old MK2 cortina on up to equal amounts of petrol and water, need to blank off the radiator at high proportions of water. Easy mod to a carburettor engine not tried it with a fuel injected engine. Similar method used in WW2 to get extra thrust to get heavily loaded bomber off the deck quicker too.

[Etaoin Shrdlu]

I always thought my old Tiger Cub ran much better on foggy days. It's also said that spraying water in the air inlet can decoke the combustion chamber, but I never tried that.

[Dave Plowman (News)]

Certainly does. It's an indicator of a blown head gasket - one or more spark plugs being much cleaner than the rest.

[Michael Chare]

Why do you care? If the head gasket has failed the pressure of exhaust gases entering the coolant is enormous and bound to force the water out via the normal pressure release valve - radiator cap.

My car overheated the other day. What puzzled me was why the coolant level was normal. Turned out the plastic impeller of the water pump had disintegrated.

[Mr Fuxit]

Not much point putting in Fluorosceine without thoroughly washing the engine,and then checking a baseline level of fluorescence. Many liquids involved in the manufacture and maintenance of engines also fluoresce under UV light.

[news]

Late to the fray; I thought that was why antifreeze was fluorescent under ultra violet?

And pressurising the system cold also allows one to see the pressure dropping and hearing an internal hiss.

If its coolant into the head there need not be mayo in the oil, similarly if its coolant getting past a cylinder liner gasket.

Coolant lost to combustion chamber can be successfully sealed with one of the water glass based sealants.

AJH