I'm wondering about most efficient way to diagnose? I've pulled the spark plugs, no obvious indications there. Will do compression check next, also check oil for water. It was overheated several times... Seems like cracked head? Warped? It has 170,000 miles on it but is still overall in pretty decent shape.

 

Is it blowing white clouds or just water dribbling out the tailpipe?

 

It is dribbling out a weep hole in front of the muffler. The water loss is significant.

 

Dribbling out the weep hole may be normal. The weep hole is there for just that reason, to allow water to escape the muffler rather than rusting it out. The water can be from condensation or a natural byproduct of a working catalytic converter. Depending on how much you deem to be "significant" it could indicate a slightly right air-fuel ratio, or it could be completely normal.

-Rod

 

I'm reading this post and asking myself what the problem is. Water is a normal byproduct of combustion. If you are loosing antifreeze thats another story.

 

Yes, it is more than condensation. There is anti-freeze in it. I estimate fluid loss is easily a gallon an hour.
We filled the block and radiator via the upper radiator hose prior to firing it up. It took maybe 2 gallons, hard to say using a garden hose.
When we started it, there was no immediate leakage on the exterior of the motor or radiator. Maybe a quart+ came out the weep hole before we shut it off.

 

If it is running that much water through the engine it should be smoking and running rough as well. Did you verify the water loss out of the engine? If you're just going by how much was on the ground, it probably wasn't that much. For a rough guide, 2oz of water will make a circle about 5" in diameter on concrete. I have seen mufflers hold upwards of a quart of water after being submerged, the puddle from that is quite large.

 

It barely starts. It does run rough. It runs steadily out the weep hole, like a leak. The puddle was 5' long, heading to the curb. The water flow was constant.


It is absolutely, positively loosing coolant. Car will overheat in 30-45 minutes.

 

Then it's most likely a head gasket and/or cracked head.