This guy installer a filtration system on his VW Passat B3. After replacing heater core he found lots of crud inside the old one. Even though the coolant has been replaced by manufacturer recommended intervals. So he used a filtration system meant for boilers/water heaters and installed it on the heater core inlet side. Being the type of filtration system that it is, it's meant for higher temps and pressures than an average ICE. After about a week and less than 300 miles he replaced the filter 7 times until his coolant became as clear as new. The 1st filter split (upon first filter change) because he got the flow direction wrong. 6 filters after that were installed with correct flow direction and didn't split. After the clean up was done he removed the filtration housing and replaced with normal heater hose, until next clean-up is needed. Thoughts?
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