Just an update.
I ordered the chemical "Tuff Stuff" (made by MARC), and received it on Christmas Eve, finally got around to using it New Years Eve. Results - It worked! It broke loose all kinds of stuff (calcium scale, lime?) from the heater core. I now have heat like when the truck was new.
I bought two 6ft lengths of heater hose & 5/8" hose mating nipples & extended the heater core lines out of the engine compartment so I could work standing on the ground. I filled the heater core 3 separate times, with flushing in between, flushing both backwards & forwards, and sometimes using shop air set to 50psi to blow the water out and create agitation. The 1st time I put the chemical in and let it sit for 1 hour, the 2nd & 3rd times 30-45 minutes.
Don't let the chemical set in the heater core for to long, and be sure to be gentle when you blow compressed air thru the system.
I ordered the chemical "Tuff Stuff" (made by MARC), and received it on Christmas Eve, finally got around to using it New Years Eve. Results - It worked! It broke loose all kinds of stuff (calcium scale, lime?) from the heater core. I now have heat like when the truck was new.
I bought two 6ft lengths of heater hose & 5/8" hose mating nipples & extended the heater core lines out of the engine compartment so I could work standing on the ground. I filled the heater core 3 separate times, with flushing in between, flushing both backwards & forwards, and sometimes using shop air set to 50psi to blow the water out and create agitation. The 1st time I put the chemical in and let it sit for 1 hour, the 2nd & 3rd times 30-45 minutes.
Don't let the chemical set in the heater core for to long, and be sure to be gentle when you blow compressed air thru the system.
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