Engine has been flushed for 3+ hours now with the engine off, no thermostat, drains open at the bottom of the radiator, the rear of the block and radiator cap removed. Just enough flow from the garden hose to cause overflow from the radiator filler. Now that I'm home I started the engine and adjusted the garden hose flow to maintain slight overflow from the radiator filler.

I'll let it run like that for an hour or so. Then shut off the engine and garden hose flow. Wait for the system to drain down, close the drains, refill with water only, burp the rear temp sensor to clear air from the system and start driving it around the neighborhood.

After 30 minutes of running in 99F air temp with constant flow from the garden hose, the back temp gauge is reading about 140 degrees and the front temp gauge is about 130 degrees.

Last edited by Bill Hanlon; 06/27/2024 8:45 PM.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.