Thank you for your reply. Yes the water heater is higher than the engine
. Here is how it is set up and what I have tried . . . 1" hose comes off heat exchanger acting as the feeder line up to an expansion tank located in the cockpit
. From there another hose comes off the expansion tank which is the return hose going to the hot water heater and then back down to the return side of the heat exchanger. It took me 5 times to flush the engine before I could get out all of the old coolant
. I have no idea why the system would not drain all the way particularly since I had the radiator cap off the expansion tank and the manifold and removed the return side of the heater hose from the exchanger. When the filled the system with new coolant
, I was only able to get it to take 3 of the 5 gallons. The procedure I used to fill the coolant was as follows: I used the expansion tank as the fill point since it was the highest point. I removed the hose from the heat exchanger on the return side and plugged it. I then began filling the coolant from the expansion tank until it came out the barbed side of the heat exchanger where I had removed the hose. I then plugged that side and unplugged the return hose until coolant ran freely from that point. Once I knew the coolant was running freely on both sides, I re-installed the hose. I then opened the petcock on the heat exchanger to purge it of air. Then I opened the pet cock on the thermostat housing to bleed it from that point. The lever in the reservoir still does not go down. I tried using a Stant coolant pressure tester to pressurize the system from the radiator cap on the manifold but all that did was backglow. I then tried to pressurize the system from the reservoir using the same procedure and that did not work. Then I went out and bought a fluid transfer hand pump and placed a hose on the return side of the expansion tank and put the other end of the hose in the coolant container and began pumping. I was able to get a little more coolant in the system but I am still 2 gallons away from filling it. I am stumped. I have been at this for 4 days now and nothing seems to work. Please help.