Cover between Clean Out Ports

[LoWeLL216]

Hey everyone,

Is the cover(?) between the clean out ports supposed to be removable or should it be sealed?

Mine looks like it's sealed, but only partially. I noticed a lot of water back there last outing.

 

[Mesa50]

It’s supposed to be removable, and water definitely seeps through it because of the clean out ports. Jet boat pilot makes a riser to elevate the cover, so water doesn’t get through it.

 

[LoWeLL216]

Stupid question - what's underneath it?

 

[haknslash]

Stupid question - what's underneath it?

The actual bilge of the boat. You’ll also find that’s where the water box (muffler) is.

Water gets in there when you come off plane. That compartment is meant to be “wet storage” and it has a drain. The tubing for the drain runs down and exits near the waterline back by the jet pumps. There is no check valve on that tubing so when you come off plane water rushes up the tubing and dumps in your wet storage compartment. That is why you see water on top of the cleanout plugs.

 

[LoWeLL216]

Thanks for everyone's help - I installed the riser this weekend and was shocked at how much it reduced the water.

 

[drewkaree]

Water gets in there when you come off plane. That compartment is meant to be “wet storage” and it has a drain. The tubing for the drain runs down and exits near the waterline back by the jet pumps. There is no check valve on that tubing so when you come off plane water rushes up the tubing and dumps in your wet storage compartment.

I can verify that adding a check valve to the tubing for the cleanout tray drain makes zero difference. I added this one below, and after having still having water in the cleanout plug holes, I tested again after corking the cleanout tray drain. Also zero difference. Enough water makes it past my rubber seals on the cleanout plugs to fill all of the area. I was hesitant to pick up Will's riser, but I've done everything other than sealing that hatch off, I just didn't want to throw the coin at that riser without anyone responding about their results. The one video I came across showed how to install it, but didn't really address whether it solved the problem, or how well it really worked.

Thanks for everyone's help - I installed the riser this weekend and was shocked at how much it reduced the water.

This is info you should share with others. Firsthand experience and what the difference was in your situation is invaluable information for those like me who were holding out. Good to know.

 

[yam240sx]

Thanks for everyone's help - I installed the riser this weekend and was shocked at how much it reduced the water.

Link to the riser ?

 

[drewkaree]

Link to the riser ?

Yamaha Mechanical Access Port Riser

Add vertical height to the location of your clean out port compartment's mechanical access port. Adding this custom "STARBOARD" CNC fabricated riser will raise your boat's mechanical access port 3/4" above the deck. Raising the access port up off the deck has the effect of keeping the bilge...

jetboatpilot.com

 

[LoWeLL216]

The link above is exactly correct.

Also, my results were basically identical to this video (the before and after) :

 

[Kevin Collins]

I lost the cover itself and cannot find the part online anywhere. Any help?

 

[Mesa50]

I lost the cover itself and cannot find the part online anywhere. Any help?

I’d order it from your local boat dealership. I ordered a part from Yamaha Sports Plaza and it took 6 months to arrive. The dealership might be able to use their parts lookup system on a National locator to find one at another dealership. Or you could make a temporary one out of hdpe plastic and some peel and stick gasket material. I wouldn’t run without the cover, and I wouldn’t go 6 months without using the boat either.
Generic, HDPE (High Density Polyethylene) Sheet, Opaque White, Standard Tolerance, 14 Thickness, 24 Width, 48 Length by Technology Island (24 X 48) https://www.amazon.com/dp/B095MFRJH...t_i_NSKQ0K22VSVP5Z7FA3AT?_encoding=UTF8&psc=1

 

[ImHowl]

The cover gives you access down into the bilge area. It is supposed to be removable. Yamaha did a HORRIBLE job at sealing this area up on my 2020 AR240. I was getting gallons of water in my bilge every outing. Water was not splashing over the deck on deceleration. If I went hard reverse, I could get a tiny amount pushing up from the drain, not enough to make any difference. All the water was coming past the clean out ports. How do I know this? I stuck a GoPro video in there and recorded it. Youtube link below.
I would remove the entire cover as seen in the photo. Clean up the area, and reseal. I also added the access port riser from Jetboatpilot. I filled the area with water and plugged the drain with my finger and can confirm it is now water tight up to the top of the access port.

 

[notaclue]

Wow - great info. I have the port riser in garage waiting to install. Hopefully that does the trick.

 

[AZMark]

The cover gives you access down into the bilge area. It is supposed to be removable. Yamaha did a HORRIBLE job at sealing this area up on my 2020 AR240. I was getting gallons of water in my bilge every outing. Water was not splashing over the deck on deceleration. If I went hard reverse, I could get a tiny amount pushing up from the drain, not enough to make any difference. All the water was coming past the clean out ports. How do I know this? I stuck a GoPro video in there and recorded it. Youtube link below.
I would remove the entire cover as seen in the photo. Clean up the area, and reseal. I also added the access port riser from Jetboatpilot. I filled the area with water and plugged the drain with my finger and can confirm it is now water tight up to the top of the access port.

That’s a great video. I have removed the larger tray and resealed and still get a ton of water. Did you do the reseal and add the riser at the same time or separately? I’d hate to spend the money on the riser and keep having the same problem.

 

[ImHowl]

I did the riser over the summer and it helped...but I was still getting water. Once I had the riser in, I filled the area with water and stuck my head in the access and still saw a lot of water leaking in from around the seals to the entire area. Once I pulled the boat out for the winter, I went ahead and pulled the entire access cover off and resealed.
Now I have zero leaks.
I recommend doing both at the same time. The access port riser has you install threaded nylock nuts on the end of machine screws. The fiberglass in the bilge area didn't leave enough room to fit the nuts, so I shaved it down some. This process would have been easier if I had the entire piece off, instead of fighting with it with just the access cover off.

 

[RobbieO]

The actual bilge of the boat. You’ll also find that’s where the water box (muffler) is.

Water gets in there when you come off plane. That compartment is meant to be “wet storage” and it has a drain. The tubing for the drain runs down and exits near the waterline back by the jet pumps. There is no check valve on that tubing so when you come off plane water rushes up the tubing and dumps in your wet storage compartment. That is why you see water on top of the cleanout plugs.

Finally have an answer why the cleanout ports fill with water! I always thought pump pressure was bypassing the seals. The seals are lip seals and should seal better as the pressure increases. Thanks for answering this mystery for me.

 

[RobbieO]

The cover gives you access down into the bilge area. It is supposed to be removable. Yamaha did a HORRIBLE job at sealing this area up on my 2020 AR240. I was getting gallons of water in my bilge every outing. Water was not splashing over the deck on deceleration. If I went hard reverse, I could get a tiny amount pushing up from the drain, not enough to make any difference. All the water was coming past the clean out ports. How do I know this? I stuck a GoPro video in there and recorded it. Youtube link below.
I would remove the entire cover as seen in the photo. Clean up the area, and reseal. I also added the access port riser from Jetboatpilot. I filled the area with water and plugged the drain with my finger and can confirm it is now water tight up to the top of the access port.

View attachment 170892

I haven't had any water get into the bilge area so far, but I still purchased the riser and will caulk around the main cover with 3M Marine Grade Sealant anyway. I now understand how the cleanout ports fill with water as well.

 

[haknslash]

Finally have an answer why the cleanout ports fill with water! I always thought pump pressure was bypassing the seals. The seals are lip seals and should seal better as the pressure increases. Thanks for answering this mystery for me.

You could also have it come from a bad seal on the clean out ports as the video shows above., so it’s worth inspection your seal if you think they’re leaking. Water will also come in from the wet storage overflow/drain tube unless Yamaha has finally started putting check valves on it with newer boats.

 

[drewkaree]

That’s a great video. I have removed the larger tray and resealed and still get a ton of water. Did you do the reseal and add the riser at the same time or separately? I’d hate to spend the money on the riser and keep having the same problem.

Fab one up, DIY style, for ~$20-25. Not sure if yours is the same size as mine, but I'm damn near convinced I could have used the scraps and the adhesive to make the second layer, instead of buying 2 boards, and it would have been about half that cost. Might not be worth the hassle though, since they're only $7-10 each. Mine is also 1" thick, vs 3/4" thick.

 

[Mesa50]

Fab one up, DIY style, for ~$20-25. Not sure if yours is the same size as mine, but I'm damn near convinced I could have used the scraps and the adhesive to make the second layer, instead of buying 2 boards, and it would have been about half that cost. Might not be worth the hassle though, since they're only $7-10 each. Mine is also 1" thick, vs 3/4" thick.

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Nice job!