RYDLYME Marine Biodegradable Descaler - 1 Gallon

Brilliant. Descaled my motor boat diesel engine coolers. Saved £££££s avoiding strip downs of coolers. Inspected cooler internals with inspection camera after flush. Spotless & engine temps perfect.

Descaler for certain. Great Descaler for my 20 hp engine. Followed the instructions on dilution, let it run overnight. Cleaned engine inside and now works properly. No more limp mode or overheating. Cheap fix rather than taking it to the shop.

works well for my DF175 outboard engine.

This stuff worked so well! My 50hp Honda outboard was having cooling issues and I thought it was going to have to be rebuilt which would have cost a fortune. I set up a 5 gallon bucket with a 800gpm pond pump, removed lower unit and pushed a 1/2" hose from pump onto the cooling water tube sticking out bottom of engine. Also used a 3/16" barbed fitting to extend the tell tale hose to bucket. Removed thermostat. Then taped a trash bag with the bottom cut off onto the engine and draped into bucket. Mixed Rydlyme 50/50 with water, and ran the pump for 3 hours. The water almost turned gray there was so much salt and junk in it! When I dumped the bucket there was a thick sediment in the bottom too. Flushed the engine really well with fresh water right away. We just took the boat out and it's like a new outboard! So happy!!

Did the job but wish it wasnt so expensive. I need to flush my motor again as this worked at about 85% clean

Very effective and videos to see how to use it. Easy to reach customer service.