Try back flushing the heater core. How? Run water through the core backwards to normal flow and see if anything comes out and how well it flows. I used a garden hose and nozzle shoved into the heater lines to do mine. Could also try something in the core to dissolve any buildup and see if that helps.

r.c.brown@ieee.org
TruckEditor@tlca.org
Project: 4Crawler
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