Drain plugs

[ZeroZX]

I’m just curious about how the drain plug work. My ski has they regular drains on it with the screw-on cap and the white ball to stop back flow if you forget to screw it closed. It also has the hose attached to them, which from what I understand is a vacuum pump that works with the engine running to pump out any water that gets in. If that is the case what I don’t understand is how the vacuum pump is supposed to work if the caps are screwed on.

 

[mikidymac]

Two completely separate systems. The drain plugs just let water out when you pull them and the ball is a just in case measure if you forget the plugs.

The bile system uses suction from the pump to pull water out and the drain plug housing is just the low point for the water to get sucked up from.

 

[Rikky001]

Correct, the bilge system is used as an ejector, it uses the water from the jetpump to create vacuum to suck out anything what shows up in the hull. It is important to keep these 2 clear hoses tied up high. I see PWC's which had the engine out and these clear hoses forgotten to tie up high - very limited working of the bilge system due to this! It is well decribed in the maintenance manual that these hoses need to be hung up as high as possible.

 

[skiasylum]

Actually the drain plugs are connected to the bailer system on my 2011, the vacuum created by the operating pump sucks any water out of hull and out the pump. The drain plugs need to be secured to create a more closed system to create a enough vacuum to expel water from the hull thru the bailers. The ball in the drain plug does the same thing as the plug when the pump is operating and creating a vacuum, it closes the system to create a vacuum if the plugs are inadvertently left out. If the pump is not operating the balls may not close the system allowing water to enter hull thru the drain and out the bailers. Reverse direction. So why did Sea-Doo engineers connect the bailers to the drain plugs? Probably to give us a second chance to not flood the hull if you leave the drain plugs out when the pump is operating.

 

[mikidymac]

Correct skiasylum but they really are two separate systems. Maybe we are all saying the same thing? The plugs are balls are one system in that the drain plugs let out water and the balls close like a scupper if you forget the plugs as a backup to help prevent flooding. If the balls or seats are dirty they can't seal and can still flood the ski. the bilge system uses vacuum from the pump to pull water out and just happen to be connected to the drain plug housing but do not rely on the ball or plug. Even the last 2-strokes with separate bailers used the plug and ball.

 

[skiasylum]

I was just trying to provide a explanation why the Sea-Doo engineers connect the bailer lines to the drain plug housing. There should be a reason.

 

[ZeroZX]

Oh so I was thinking about it backwards? The hoses use that as the vacuum point and ejects the water out elsewhere, not using the drain ports as the exit point.

 

[mikidymac]

Correct, they actually pull water from that location and blow it out the back of the jet pump.

 

[ski-d00]

The reason the engineers did it that way on the newer skis is because they eliminated several extra parts(bailer housing, bracket, rivets). By combining the two systems into the same housing, they reduced part cost, assembly cost, and freed up some space in the bottom of the hull.

 

[skiasylum]

Well we just had another unfortunate new to jet ski person have his almost new jet ski sink because of one of those stupid drain plugs not being secured properly. Apparently the white marble doesn’t work very well when the ski is just sitting in the water. Guess that is why we have insurance. Maybe some guidance on drain plug usage might be warranted. Personally mine never get unscrewed unless it’s on the trailer in the garage.

 

[mikidymac]

I think teven the newest person to watercraft have been informed over and over to always check your drain plugs. It is one of those things that is just going to keep happening no matter what you tell people. Just like leading a horse to water.

The proper technique is any time the ski is on the trailer the plugs should be out and whenever you get the ski close to water the plugs should be the first thing you check.