Easiest is to pressurize the system with a pressure tester, then look for the leak. That's not always easy because it can be buried. On my 3.0L, when the tube or O-ring leak, coolant will run out on top of the transmission bell housing on the driver's side of the engine if it's parked with the right tire a little higher than the left tire.
There is also likely to be a small diameter bypass hose above the water pump that is a common source of leakage and very inexpensive. Head gaskets are another issue. You might see white stains running down the block where coolant had been leaking.
How fast, or how much does the coolant leak? When my water pump went out years ago, after filling the radiator, I had a hard time going two miles before it was all drained out and the engine started to run hot. Made a lot of noise too.
For very small leaks, you can purchase a small bottle of dye to add to the coolant. After driving it for a while, you look for bright yellow stains when shining a black light on the area.
Saturday, July 25th, 2009 AT 5:54 AM