After reviewing the workshop manual I found a section dealing with reverse flushing the cylinder block and decided to give it a go... In my mind there were three things to do before having to do the extreme, which was to pull the cylinder head to clean the water passages:
1- Reverse flush the block, and use a wire to loosen any rust scales and crud from the rear left side of the block. 2- Use compressed air through the same opening to help move the stuff around... 3- Remove the water pump if necessary to clean scales from the block accumulated in that area...
I spent quite a bit of time with that setup that allowed me to do that until I got nothing but crystal clean water from the rear petcock, as well as what was being drained from the lower section of the block up front... I alternated that and blowing compressed air though the rear opening to loosen stuff up. After 3 hrs. of that, I decided to put it all back together and run the engine... To my surprise the engine run about 170F without the thermostat and never reached 180F. Success at last!!
In the next few days I will use my old Delco 180F. thermostat and a 50/50 mix of antifreeze (despite being in Fl.) and finish the job as it should be...
For all you guys who do not believe in antifreeze in warmer climates, do yourselves a favor and save your blocks, heads but mostly water pumps from corroding and forming rust barnicles by using antifreeze... I removed the water pump from the original engine and despite not leaking or having any play, the impeller was ful of calcium and rust deposits from water usage instead of antifreeze...
As all you guys out there know with early 216 engines, single hole water pumps are expensive and imposible to find, so save what you have and use antifreeze instead of water on your engines!...:)
