You say you were moving a car with yours and steam was emitting from the exhaust. How long had the Sportrak been running and what were the weather conditions. On start up engines produce a lot of condensation that is discharged into the exhaust system as vapour. On cold mornings/days this can last a long time and as the engine heats up will decrease once all the condensation is dried out of the system. On a cold morning/day this is worstened as the hot exhaust immediatly condensates with the outside cold air, that why cars appear to steam at traffic lights in the winter. It is steam but not from the car directly but where the hot gases are meeting with the cold air.

Had you checked the coolant level before the tow begun or as a result of the steam you saw? It is quite likely that the level was already low and you are worrying over nothing, bearing in mind your statement that the car did not overheat.

There are many symptons that indicate a blown head gasket, the most common being the slurry that forms in the oil from mixing water with oil. It appears as a salad cream and is obvious on the bottom of the filler cap abd on the dipstick. Overnight the water will rise to the top of the oil and be obvious on the dipstick. Additional symptons are overheating, were high temperature exhaust gases superheat the water and up goes the temperature guage.

I'd be tempted to monitor the loss of water over a few days checking that their are no obvious leaks, check the oil and the water for the dreaded "salad cream" and keep an eye on the temperature guage. If it rides high then you have an overheating problem which could be the head gasket. Use the heater and it's fan to cool the system to get home if necessary.

Daihatsu engines are quite long lived and would be well worth repairing if the mileage is correct or even double.
Oil often gathers on the edge of the cylinder head and block joint as well as on the top cover and the head joint.

The gasket often causes a ledge where stray oil accumilates. I would clean all traces off and then keep an eye on it. It may be a spillage or even where the dip stick has caught. Oil spreads and often looks much worse than reality. I doubt unless you have a warped head that oil is escaping from the gasket.

As far as I am concerned none of the solutions like rad weld or bars leaks provide a long term solution but if I were thinking about trying one then I would go for BARS LEAKS whick contains a lubricant for the water pump as well a brass filings to seal any tiny leaks. In the past this is the only one that I have used that worked but not long term.

So my conclusions are that the level may well have been low before you sarted the rescue attempt. As the engine did not over heat whilst hauling the other car, that is good and unless you find oil and water contamination or overheating then the head gasket sounds ok. The oils should be thouroughly cleaned off and then watched as should be the temperatur guage. Running it into the ground as you say is probably what we are all doing as the values are continuing to drop off.

Hope some of this is of use

OLDMINIMAN