How do I ensure there is no water in this boat motor?

"Highlander-Datsuns are Forever" (jamesbowland)
12/04/2016 at 13:02 • Filed to: boat oppolink, boaty mcboatface

Google has failed me OPPO. Does anyone have experience with a newer Yamaha 40 HP outboard Jet? I need to make sure there is no water in the Cooling system since we store it outside and it will be 7 deg F tomorrow. The boat is currently taking up garage space from my Subaru and Mazda.

What I have done: disconnected the flush hose and blew it out with compressed air, about 1 oz of water came out that was it.

The flush hose is that 1/4" hose screwed onto the outside of the engine. You can connect it to a garden hose to flush the cooling system after running in dirty water.

What I was also thinking,

1. take off the thermostat housing and blow it out, making sure there isn’t any water in the top of the engine. But this motor may be self draining, I just don’t want to be responsible for ruining a very nice outboard.

The thermostat housing is at the top of the engine with 2x 10 mm bolts holding it in, should be easy to remove.

2. Force flush through the flush hose some anti-freeze (not my preference because it will be messy and some of that will go into the next river we put the boat into.)

DISCUSSION (7)

gogmorgo - rowing gears in a Grand Cherokee > Highlander-Datsuns are Forever
12/04/2016 at 13:09

You could always run the antifreeze through it, and then blow it out again, or flush it again before the next time it hits the water. You could also go with RV or plumbing antifreeze which will be less environmentally damaging I think.

Highlander-Datsuns are Forever > gogmorgo - rowing gears in a Grand Cherokee
12/04/2016 at 13:11

Excellent idea thanks!

HammerheadFistpunch > Highlander-Datsuns are Forever
12/04/2016 at 13:12

If you use anti-freeze just use propylene glycol, its non-toxic....though it would be best to flush it on land instead of the river because it consumes a lot of the oxygen in the water column. I winterize a 9.9 and a 55 2-stroke every year and I just run it dry with the engine trimmed down for 5 seconds or so, that seems to get it all out without fear of burning up the impeller.

HammerheadFistpunch > Highlander-Datsuns are Forever
12/04/2016 at 13:17

To be honest, my biggest fear with winterizing outboards isn’t the water...there usually isn’t enough trapped in there to do any damage...its the garbage juice being sold as gasoline these days. gummed up jets are my biggest issue in the spring. I either run a significant amount of stabilized ethanol free fuel though the engine (my 9.9 takes a solid 10 minutes of idle to refresh the bowl) OR I run them both completely dry until they sputter and die and refuse to restart.

For Sweden > Highlander-Datsuns are Forever
12/04/2016 at 13:20

wave it in front of a rabid squirrel.

You should have a sailboat for Flathead btw

Highlander-Datsuns are Forever > For Sweden
12/04/2016 at 13:40

We were running on the flathead river, cold AF.

Highlander-Datsuns are Forever > HammerheadFistpunch
12/04/2016 at 13:42

Agree with you on that, I only use 91 octane ethanol free gas. I could go get some stabile and run that through as well. It did start up and no additional water came out.