This thread seemed like a good place to ask for other's experience. I have 2011-2012 5093e limited with 6400 hours..yep 6400 hrs. I used Fleetguard/Cummins Restore Plus at about 1/3 gallon for the 3 gallon cooling system as label directed. Spliced in a "T" below the cab step for back flushing "just because" and assumed municipal water pressure would be enough to flush up the supply heater core out return. While doing this I had 1) both the right side and left side engine block drains open 2) then closed the block drains and put cap on the expansion reservoir and filled cooling system from tap and operated at temp for 10 minutes. 3) Opened up the block drains again and allowed to drain as well as "T" splice /port I installed at the lowest point in the heater core supply loop. Heater control valve was wide open. Bone dry as far as I knew after the draining 4) Refilled coolant at 5 quarts concentrated coolant to 7 quarts DISTILLED water. Everything running fine . No overheating but NO HEAT. Got a coolant sample from the "T" and it cloudy with rust flakes and when tested the coolant concentration was only good to "0" degrees but should be -15F degrees. I'M THINKING THAT EVEN WITH ALL THAT FLUSHING THERE MUST HAVE BEEN CLOSE to the entire heater core, supply and return lines left full of the COOLANT system FLUSH solution.
So now, since I need to replace the sediment-full, "0" degree protection coolant/flush combination I am also going to replace the THERMOSTAT.
QUESTIONS:
1) Recommendations on a better way to flush the Heater supply, Core/exchanger, return lines? My thought is to move the flushing "T" to just in front of the cab roof
valve under the cab access pan. Flush with tap water, then run some compressed air to empty the core.
2) Recommendations on how to refill coolant level to include or "charge" the heater core supply, core/exchanger , return line to eliminate possible "air lock" for the heater not heating the cab after the flush/recharge? Refill from the same "T" at this higher elevation? I do have a drill powered pump.
3) Anybody with recommendations or experience replacing the thermostat in the 5093e limited (Engine group 4045HLV60). The thermostat housing is R529893, the gasket is R502814 and the thermostat is DZ100555. Will all the "O" rings for the two adjoining lines need to be replaced or can the housing be moved off the block enough to get the thermostat out without detaching the lines.
I'll take and appreciate any help or recommendations other have any of these questions. Thanks