Cold weather lower unit up or down

B

Bill Ferrar

Well-known member
We were talking at the dock yesterday. 1/2 the engines were lifted out of the water the other 1/2 were down.
2 guy said down was correct ,2 said up was correct, 1 it did not matter.
Which is correct for cold weather condition?
I leave the lower unit down when its well below freezing and up when its above freezing.
What do you do?
 
Hey I leave mine down in freezing weather when it's up it will freeze, and when I'm done I start it for 3_5 seconds and that will dry it out.
 
Not a mechanic and always left mine in the water on some very cold days and didn't have an issue. Only time I pull it is on the shallow tidal flats as I do not want to find it buried in silt on a dropping tide.
 
Mornin', Bill~

Many years ago, SSWA had a local OB mechanic talk to the club. As others here have said, he advised keeping the lower unit submerged to prevent freezing. If I had to tip it up in severe cold - because there was not enough water beneath the boat - I would let it sit in the water for a few minutes before starting when I got back to deep water (I could usually do this while picking up the rig).

All the best,

SJS
 
Not that we get that cold down here...we do sometimes and I'm on the water at least 3 days a week year round working for the DNR. Keep the lower unit below water to keep the impeller water from freezing. The ears on it are fairly fragile and can get torn off if the water in the water pump housing freezes. With the motor all the way down, most of the water in the system will flow out from gravity when the motor is shut off. When trailering and it is below freezing, when the boat is first pulled out while you are tying things down, lower the motor and crank it for about 3-5 seconds as mentioned earlier. This will pump out the system quicker...then leave the motor down while you get the boat ready to haul home. The last thing you do before jumping in the truck is raise it up to your normal trailering position. By then, all the water should be drained out of the motor. NEVER crank a cold motor in the dry before it is first put into the water. You can crank a wet motor out of the water for just a few seconds but don't crank a dry motor out of the water...the water pump housing on many is made of plastic and that rubber impeller fits tight to that plastic housing. With no water in there and that rubber starts spinning against that dry plastic, the friction from the two will melt the plastic and rip the rubber ears right off of the impeller. Then you are replacing the entire water pump instead of just the impeller. Store the motor in the down position also. That way rain water can set in the prop housing...if it freezes it can do some seal damage.
 
Can't speak for the cold weather but the lower unit should always be stored down & in a level position.

When up, many of the internal seals, rings & gaskets will only be partially lubricated, drying up & weakening seals on the back ends.

Rust will also form around the piston rings & after long down times can crack the rings on starting.

The rust can also score the piston wall.

Taking it a step further, you "should not" run all the fuel out of the carb's.

Again, it causes the internal seals & gaskets to dry out.

If you're worried about what & gunk building up (which you should), keep tank full & use Sea Foam or Marine Sta-Bil (blue).
 
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