Austin 10 Steam, pouring from overflow

[Oxfordchap_2003]

I'm happy to be part of this forum and as I have recently purchased a 1935 Austin Ten Lichfield. I'm relatively young so I don't know too much about car mechanics but I'm willing to learn and I think there's probably no better car to learn on. The car stood in a dry garage for 20 years without starting before I bought it. A friend of mine who knows a thing or two came with me to check on it and thought it's in overall good condition.

We did two oil changes, changed the spark plugs, removed the elbow at the bottom of the engine block which leads to the bottom of the radiator and flushed out the radiator and engine block with a hose, and water seems to have travelled through the radiator and through the block freely, removing some debris in the process. we stuck the elbow back on, drained the remainder of the water and filled it with around 1 1/2- 2 L of coolant, so I'm not sure how full that is, and we ran the car. after about 5-10 minutes of the car running, steam began to come out from the overflow pipe that runs down the side of the radiator, depositing a few drops of water in the process too. We also noticed a bit of steam (not much) escaping from the radiator tap.

The owner's manual says to fill the radiator almost 2 inches to the top (which i did not do) whilst the termostat is open. My car has no thermostat. Other people have told me that I don't need so much water and that the steam and water drops is simply the thermosiphon regulating itself and throwing out the excess. The thing is, I don't think there is that much to have an excess and I don't know how much there is left. What is the expert advice that one of you might be able to give me please?

[phil_taylor]

You need about 14 pints or about 8 litres of water otherwise it will boil. (You can fill it up to overflowing and the surplus will come out of the overflow as it heats up and expands).
Cheers
Phil

[peter_winney]

Your choice of car is a good one. Simple and sturdy design that is easily worked on without too many special tools or test gadgets.

You need more coolant in the radiator than 2 litres. For a Lichfield about 8 litres as Phil says. Remove the radcap & have a look into the header tank with a torch. You will see the top of the radiator core. This needs to be covered by the coolant otherwise it will not be able to circulate in the system, hot coolant rises to the header tank then after cooling in the radiator goes back into the engine block via the bottom water elbow. Otherwise you have done all the right things flushing radiator, block & elbow etc.

The thermostat mentioned in the handbook is a red herring as most cars no longer have this feature. It fitted into the top hose and in theory assisted fast warm up of the engine by preventing the circulation of the coolant until it was warm enough. In practice many of these gadgets failed closed (rather than open which would have been fail-safe) and caused overheating and so were removed.

The "2 inches from the top" measurement is about the level that the coolant settles down to. More than that and it will blow out of the overflow. Before starting the car when it is cold you can test the level in the dark by dipping your finger in. But not if you have antifreeze. The system is not pressurised like a modern vehicle but when it gets too hot steam can build up pressure as the overflow does not let it out fast enough. So never remove the rad cap when the car is hot, let it cool down for awhile. I know someone who scalded themselves when they undid the cap and released the steam pressure. At the top of an Alpine pass I saw someone else remove a rad cap which then soared up into the air from the released pressure. Austin 10s do not usually overheat to that extent and keeping the car moving, with airflow throught the rad, is usually better than stopping, unless the cause is low coolant level.

Enjoy your 10