Is flushing an engine a good or bad idea?
An engine that is properly maintained should have no sludge. However, that being said, there are reasons you might encounter an engine that is sludgy. Mechanical issues such as coolant in the oil can cause sludge. Also you may have purchased an older car that you found interesting, but the engine is sludgy.There are things to consider when flushing an engine and selection of a good quality engine flush can go a long way to having a good end result.
This blog post is the most complete and concise information you can find on flushing an engine. I highly recommend it:
"Is an engine flush good or bad?"
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