· Commercial Member
some have but it is not a good idea. Given all the small passages in a cooling system, that stuff will cause you more problems than it will fix. Heater core replacement is really not that bad of a job. I did mine a few months back in about 6 hours. That was my first time doing it and taking my time. That 6 hours also included putting in a new evaporator core, accumulator/drier and A/C compressor.