Will closed loop cooling for outboards ever take off?

[Dankoozy]

Seven marine had closed loop cooling on theirs but then the Swedes quickly decided to discontinue them. Pumping salt water and sand through an engine is not ideal and appears to be what causes the death of a lot of outboards.


Some dude was given a patent for it as recently as 2017 https://patentimages.storage.googlea.../US9545985.pdf


I am honestly surprised the concept hasn't been developed further

[Poly]

Its commonplace on inboards (using a raw water circuit and a heat exchanger) so it is unlikely that nobody in the outboard companies has given it serious consideration. Obviously adds weight, complexity, service components and moved the potential failure points from the block to the cooling circuit. But its not like inboard engines never experience cooling issues.

I suspect that the death of most outboards is not salt water cooling per se - but poor maintenance. Flush the engine regularly and you probably move the failure mode from block to electrics. Do outboard companies care if engines fail after 20 years though? No - that generates new sales.

[Erin]

Finding somewhere to mount the radiator (raw water to coolant) is probably the real problem.

[HDAV]

For modified car engines it makes sense, for marine specific motors less so….. and for outboards even less

BRP run closed loop cooling in seadoos Yamaha and Kawasaki don’t…….

BRP pulled out of the outboard market but are heavily into PWC and boat markets

[Matt]

Cost, size and complexity.

You can easily get 20 years out of a motor that is flushed regularly, but the kicker is for inboards that stay in the water. I converted my to indirect cooling on my V8 and it’s nice - but the heat exchange and plumbing all takes up space and costs money. I did it for engineering “nicer that way”, but the actual short term benefits are….