How much can I safely dip the stern?

[4_Ever_Newbie]

I’m concerned about water getting going past the manifold risers through the exhaust and into the engine cylinders when raising or lowering the boat from the lift.

To lower and raise my Sundancer 260 the lift guy keeps it at a steep angle with the bow up (or air gets stuck in the lift’s rear pontoons and boat gets stuck), so they taught me to dip the stern almost to the point the swimming platform gets wet about 1/3 of the way...only then you start leveling the bow.

Have gone through this a couple times and I haven’t had issues....but

Is this safe in terms of water getting into the exhaust ?. Single engine, duo prop Bravo III

 

[Bt Doctur]

never heard of such a thing ,sounds like a design flaw. If that was true you would have to lift it the same way

 

[BillK2632]

I don't think you have a concern. For a couple of reasons:

1. You should have exhaust flappers in place in the exhaust Y pipe. This is basically a one way valve to prevent water from running back up through the exhaust.

2. Water is most likely to come back up through the exhaust when backing into heavy waves (ie backing down on a fish) or if you come off plane quickly and water rushes backup through the exhaust at a low rpm. Flappers are designed to prevent these types of conditions.

3. When you are lifting the boat like you describe, there is nothing pushing water into the exhaust, even though the swim deck/stern might be much lower than normal, with the bow lifted the engine is probably higher above the water line than if floating level and any water in the exhaust would be draining OUT of the exhaust.

Probably good to think this through, but I would not worry.

 

[Lazy Daze]

It's not uncommon to back a boat into the water (on the trailer) and have the platform go partially under water. If it gets far enough into the water, it then starts to float. I suspect the same holds true in your scenario. If you get the stern far enough in, it will then start to float. I think it would have to be a REALLY steep angle before there's a possibility of water ingestion. From what you're describing, it sounds like a similar angle to a ramp. Essentially, the manifold elbows always stay above the waterline.

I don't know much about lifts, but I've seen them used many, many times. They always seem to go up and down level. Is the lift undersized for the boat?

 

[4_Ever_Newbie]

Thanks for the comments guys, sounds like not much to worry about, and yes, the angle is similar to what a boat ramp would be....

This lift has pontoons with internal rear and front air tanks, you need to keep the rear always lower when handling the boat, then you level the front last.

 

[4_Ever_Newbie]

Pic

 

[boatman37]

Haven't really checked mine when unloading from the trailer but do know my platform was wet when i pulled it a few weeks ago. Could have been the splash from power loading? Anyway, I noticed one that same day (think it was a Silverton 310). The swim platform was underwater as they were loading it on the trailer

 

[Bodkin Creek George]

Our boat is lift kept and never had a problem

 

[Bodkin Creek George]

Our boat is lift kept and never had a problem