Motor Medic Engine motor flush 604 MF-3

Great product! Works! Bought it again!

Great product, been using it for years

used this for years when i get a new used vehicle, or when my vehicles get older (say every 15,000 miles or so). really, really, really cleans out the engine when used as directed. recently had an older toyota prius where the engine was getting a litlle bit noisy (ticking). used this and the ticking is gone and the engine runs smoother. a miracle product. some years back i had a sticky lifter in an older vehicle. tried this, but still had the sticky lifter. but, when i opened up the engine to get to the sticky lifter, everyone at the shop where i worked commented that they never saw an engine with 80,000 miles on it look so clean inside. never. it was simply amazing. safe to use when used as directed. highly recommended.

Didn't really work with my blown head gasket

It works in my 2000 Altima, which can removes soft sludge. But, for the hardened sludge, it beyond Gunk's ability. My car experienced over heating (up to 210F) and knocking problems for more than 2 years due to a malfunctioned thermostat. I changed the engine head gasket twice to fix the oil leaking in 2015 and 2016. In the first time, I did saw the sludges existed between cylinder 1 and 2, and between 3 and 4. It may also existed other place inside the crankcase, but I just couldn't see it. Then I bought GUNK Engine Flush MF3 and did a flush before I changed the oil, the thermostat, and the engine gasket (again) two weeks ago. I increased the flushing time from 5 mins to 10 mins. Just want to make sure, Gunk removes as many as the sludges. When I opened the engine head after the flushing, I can still see the sludge at the same place. But, it is getting smaller than before (maybe 20% smaller) and the over crankcase looks like cleaner than before (first time). Then, I removed the rest sludge by force. It turns out the rest sludge is hardened so much and attached to the cylinder block firmly. I had to use a small spade to break the sludge into small pieces first. Then, remove them by a tweezer. After all, I installed the new gasket, changed the thermostat, pour in the new synthetic oil. The engine runs like new! I feel lucky because the hardened sludge is not everywhere in the crankcase. The coolant temperature now is between 178 and 195 F. Hopefully, no sludge will be hardened by the high temperature any more. All in all, GUNK can remove those still soft sludge and do the flushing work nicely. But, if the sludge is hardened such as my case. GUNK is not the final solution. I will definitely reuse it again before the next oil change.