Outboard Flushing

 Looking at a 2016 Caribbean reef runner with a 150 hp Honda outboard,He’s had it moored in a bay in Sydney for about 3 years taking out yearly to be serviced and anti fould,the outboard done 176 hours,  I asked him how he got on flushing the moter out after every trip he replied he’s never flushed it out said don’t need to on the newer Honda’s and got told by the mob that services his boat that. I think it’s a load of bullshit. Any Thoughts?? 


Darren253's picture

Posts: 570

Date Joined: 23/07/16

I flush religiously...

Sun, 2019-12-29 10:42

But I have a mate who has a 06 Gulfcraft with a Suzuki 250 that has never seen or been flushed with fresh water in its life. 750hrs and going strong and a clean bill of health from the mechanic.

i think he probably gets internal anodes, impeller and thermostat changed on an annual basis/service but I was quite shocked about this. I too expected an engine to be destroyed if it wasn’t flushed regularly. It is always stored in the raised position so all water drains out after use.

He has owned the boat now for 4/5 years.

ranmar850's picture

Posts: 2702

Date Joined: 12/08/12

it doesn't matter with motors that are used on a daily basis.

Sun, 2019-12-29 12:48

 look at commercial outboards used on a daily basis--never flushed, swapped out at 5000 hrs or more. I always flush at home, but, if I am away for a month, it doesn't matter, because it is being used every day. It's more about having deposits build up in corners of the cooling system which can ultimately affect water flow and heat transfer, IMO. Happened a lot with older 2-strokes. 

I wouldn't be unduly worried about a boat which was left in the water and not flushed for a few years from new, if it checked out in all other regards.  If you buy it, make the effort to run it in a tub with Saltaway or white vinegar to clean out any deposits which may have built up.