I need some advice...I have a long history of = cooling system pressurizing problems with this van which all started after the water = pump failed at about 75k. After resealing the heads a few times I found = that it was just the left head that seemed responsible. So, I reseal the = left head which solves the problem and it lasts about 10k before the cooling = system starts getting pressurized again at which point I reseal the left head = etc. Most recently the pressurizing got so bad that the seal on the left head catastrophically blew and I lost coolant to the ground for the first = time. Assuming the left head was at fault again I resealed the left = head, but this time it didn't fix the problem as I'm still getting pressurized = coolant

-With a pressure gauge on the coolant tank I took a = drive of about 5 miles @ 50-60mph. When I got home the gauge (a 15psi = gauge) was pegged. This to me confirms that I have a compression leak = over the barrels (or through the heads....to grandmother's house we go) and not = just incomplete cooling system bleeding etc. Am I right?

- When the engine was cold, I released any cooling = system pressure and I then took an air compressor and connected it to each = spark plug hole, developed 65psi air pressure and held it for about 5 minutes = on each cylinder. Watching the pressure cap gauge I was hoping I would see = my coolant pressure gauge rise when I pressurized the faulty = cylinder. No luck....the pressure cap gauge never budged over 0psi on the = coolant. Why can't I duplicate the leak this way?????

My dilema is that the van is getting on in years and = I don't feel like sinking a whole pile of money into it. Should I buy = rebuilt heads? Should I pull the heads and have them tested somehow? = If my pressure test didn't show up a problem, how would a bench test? = Could I be doing something wrong that is causing this problem to recurr? What = is the proper way to test the motor to isolate where the problem = is?