[David Eidell]

Lots of money spent for new water pump and radiator. All because (I think) I could not lay my hands on a radiator pressure tester down here in México for love nor money.

The car would mysteriously overheat. The surge tank would not work like I thought it should. Turned out the be a small leak in the water pump suction line underneath the V-6 manifold.

The radiator would lose an inch or so worth of coolant and the car would overheat. It seems as though the radiator had been micro-precision sized for this car and ANY loss of coolant causes the car to overheat. The stupid thing would suck air and cause a coolant loss. Maybe a lack of water pump capacity as well.

The "leak" had to progress beyond the point where it would suck air and actually start a loss of coolant. The junction of the steel transfer tube under the manifold to the water pump suction hose is impossible to see, without partial intake manifold disassembly.

What a PAIN! Now I'm wondering if a relatively inexpensive pressure tester kit can be found. Probably an expensive and unneeded purchase but his thing drove me nuts for years. It would have been SO EASY to find with a pressure tester!

Hope this can help someone else.

 

[John Wood]

Thanks for the report. There may have been two conditions caused by drawing in air through a bad suction tube (probably a bad O-ring). Air in the pump would likely cause it to not move fluid at all and air surrounding the thermostat could act like an insulator, causing delayed opening.

The water tubes on the 3.0 are definitely a PITA to deal with. They can either rust through or the O-rings that join the sections get cracked over time allowing leaks.