Popping cleanout plugs like champagne corks on NYE... (Yes another thread)

Just purchased the 2011 Yamaha SX240, (my first jet powered boat, after multiple IOs) Took it out on day one and the starboard side impeller manhole cover had a "forceful automated removal" breaking the latch on the hatch, and landing on top of it. So we came back in on one engine as slow as possible. Troubleshot, realized there were kill switches back there keeping the port side from starting.. fixed the latch, rebuilt the lower half of the Starboard side plug that came out, cleaned it yadda yadda, put it back in and got a good seat.

Well 2 days later, we took it back out, and the port clean out plug came 90% out, lodging at the top of the hole at 45 degrees, and we almost went the way of the titanic before I realized we were taking on water. Quick run to more shallow water where we found a courtesy dock at a restaurant.. we were heading there anyways so it worked out... I'm guessing 400 to 500 gallons of water made it in with the blow out ok maybe not, but enough to come half way up the motors and into the ski locker.

So since I had the parts on hand, I rebuilt the lower half of the Port side while the bilge pump pumped away. Cleaned it up, popped it back in to ensure a good fit. Hopped into the water felt around to make sure I didn't lose the actual bilge plug.. all good there.

I have a mechanic at the Dry Stack / Marina checking the other below water line seals.

So my go forward plan other than wait for a "Diagnostic" bill from Mr. Marine mechanic as a safety check...

1) Buy a second bilge pump just in case.
2) Pull the impeller clean out plugs next time I am out there and just clean the F out of them, and inside the housing where the dogs lock.
3) I bought the EZ Locks, just waiting on them to come.
4) I am going to follow some of the other recommendations and seal the "access hatch" way better than what it is.. (Ill post a follow up there, I am pretty crafty and building on what some of the other folks have done, I think I can give it a new spin)
5) Bought audible water / leak sensors for the bilge that Ill position around.
6) Add a couple of nerf footballs / noodles for good measure
7) Say a few Hail Marys
8) Try try again.

So why post this beating of a dead horse?

I am curious how much water can really come in, and end up in the bilge, when the second gen T-Handle type plugs blow out like that.

Does anyone have / has anyone seen, a Go-Pro video of a blowout in action? Any "Sea Chantey's" written about this that gives an idea of if I am making up that the water came from the blow out? There was a lot of water, and cant help but think this is a dumb design, but at least we didn't sink..

Do not place footballs on top of the clean out plugs the worst blow out is when the plug does not pop the hatches and shut down the engines but fills the engine compartment with water and that can get really expensive do research here the blow out plugs like you have were in use from the model year 2000 to 2016 in 2017 they changed back to twist in plugs remember the bottom of the plug is the bottom of the boat and there is a lot of force on them. The EZ locks were designed at the request of Yamaha jet boat owners who wanted an easy and inexpensive solution to plug blowouts and when the EZ lock stops a blow out you will know as the lock won't release until you reset the T handle and remove the pressure on the lock ends.

Got it. No footballs / noodles. Bad advice floating around here as well. The locks are on the way, and I would second that if the second blow out would have broken the latch on the lid like the first, I would have probably noticed before the bilge filled up like on the second one. So are the broken hatch latches just something Yamaha JB owners with these have to deal with? That's the only way its going to open and kill the engine. The second one was still lodged in the hole at the top so it is as you mentioned.. bad..

The plugs you have were called blow out plugs and there is a ton of info on them . The person who talked me into analyzing the cause of the blow outs and coming up with a easy and inexpensive solution to this issue actually had a blow out when running W O T the plug blew open the hatch violently and launched in the air then it landed in the boat nearly striking his wife in the head. Just like the person who asked me to make steering for these boats way over 2 decades ago this customer brought me the plug and said find out why these blow out and please design an easy way to solve the problem.
As soon as I took the plug apart and saw the small plastic trey being contained in a track and being pushed forward by a small spring so that a round horizontal bar would snap into a notch cut in the The T handle shaft to secure the locking dogs in the aluminum ring to hold the plug in place I knew the issue was being caused by dirt that came into the plug body via the locking dog openings, these plugs always have water entering them from the pressure in the tube..
The water has sand silt etc suspended in it and when it evaporated it left the silt etc behind in the track to obstruct the forward motion of the tray thus keeping the round bar from going all the wat into the t handle shaft recess.
The solution was obvious and I still make the EZ locks as you learned .
You Put it on the plug, place the plug in the hole push the T handle down , when it goes down all the way the ends of the locks snap shut and keep the dogs in place . To remove the lock simply squeeze the lock to open the ends if the lock does not release you must reset the the Handle to release the lock ends.
This tells you the lock saved you from a blow out. So once you get your locks installed you should be just fine.

I prefer to understand the risks and then make a decision, myself. I know many folks who have run with footballs. The risk Jeff highlights is legit, but the counter-risk is that without the footballs if you have a blow, it is going to go into the hatch. It cuts off the motor because of the damage it causes to the hatch... So which risk is greater? If I didn't have the EZ locks, I would probably have footballs in there, with a bilge flood alarm (which is a good idea anyway). So I can't say that is wrong, but I can say you are taking risks by putting them in there that you won't permanently damage your boat and bring it to a halt.

As to how much water a blown plug can put to your bilge, lots of factors there. The water gets in there because the pump is pumping up into the wet storage area (if it doesn't infiltrate the tube--which is possible, too). Basically, as it comes stock, the place is a sieve. If you seal up the tray, make sure the access port gasket is good, make sure your band clamps on the tube are solid and the ones on the drain port, then the amount of water getting in should be a lot less. However, there are lots of folks who have pulled the tray and never rehooked up the drain port--then you have massively more amounts of water getting in there. Keep in mind also that if the hatch does not blow, the full force of the pumps is pumping water half out and half up into wet storage. Sure, some will leak out the edges, but basically you are putting pressure all around with water looking to get out under a good deal of pressure. So it finds the weakest point and bursts into the bilge.

Upshot of all of that is that I would recommend the bilge alarm first. Then EZ locks, which are a very good idea and have worked well for me. In the interim, footballs? But if you understand the risks and go a different direction, you are the captain, and you can certainly do that.

tdonoughue said:

I prefer to understand the risks and then make a decision, myself. I know many folks who have run with footballs. The risk Jeff highlights is legit, but the counter-risk is that without the footballs if you have a blow, it is going to go into the hatch. It cuts off the motor because of the damage it causes to the hatch... So which risk is greater? If I didn't have the EZ locks, I would probably have footballs in there, with a bilge flood alarm (which is a good idea anyway). So I can't say that is wrong, but I can say you are taking risks by putting them in there that you won't permanently damage your boat and bring it to a halt.

As to how much water a blown plug can put to your bilge, lots of factors there. The water gets in there because the pump is pumping up into the wet storage area (if it doesn't infiltrate the tube--which is possible, too). Basically, as it comes stock, the place is a sieve. If you seal up the tray, make sure the access port gasket is good, make sure your band clamps on the tube are solid and the ones on the drain port, then the amount of water getting in should be a lot less. However, there are lots of folks who have pulled the tray and never rehooked up the drain port--then you have massively more amounts of water getting in there. Keep in mind also that if the hatch does not blow, the full force of the pumps is pumping water half out and half up into wet storage. Sure, some will leak out the edges, but basically you are putting pressure all around with water looking to get out under a good deal of pressure. So it finds the weakest point and bursts into the bilge.

Upshot of all of that is that I would recommend the bilge alarm first. Then EZ locks, which are a very good idea and have worked well for me. In the interim, footballs? But if you understand the risks and go a different direction, you are the captain, and you can certainly do that.

Click to expand...

"Look at me Irish... I am the Captain now." That's what the last statement made me think of..

That being said, most of my list got done this weekend.

1) EZ Locks: Lived up to their name, installed both in under 10 minutes.
2) Bilge and Ski Locker Water Alarms: Installed, tested, Wife Hates the sound so I know she will hear them for sure lol.
3) Second Emergency Bilge purchased (1500 GPH)... yet the hose is too short to be easily used, as is the power cable, so some additional work there to have an emergency back up that I can also use to help fellow boaters.
4) Checked the access hatch and tray seals... 99% functional so I am going to wait for the off season to strip the old and replace.

Took it out yesterday, ran it at about 45 MPH for a good hour or so on a choppy/wakey Lake Travis... top of the plugs were dry, not much if any water in the bilge... I am thinking what did make it back was just residual from other parts of the boat (here's to hoping and I don't have other issues) I am still going to have the mechanic at the dry stack give it a once over for the hell of it.

Based on the EZ Locks being in there and the plugs not having water on top of them after yesterday, I think I will forego the nerf footballs and leave those for the Longhorns to learn how to play some offense before the Red River game next week.

Thanks for all of the input and help.

CauseTheImplications said:

"Look at me Irish... I am the Captain now." That's what the last statement made me think of..

That being said, most of my list got done this weekend.

1) EZ Locks: Lived up to their name, installed both in under 10 minutes.
2) Bilge and Ski Locker Water Alarms: Installed, tested, Wife Hates the sound so I know she will hear them for sure lol.
3) Second Emergency Bilge purchased (1500 GPH)... yet the hose is too short to be easily used, as is the power cable, so some additional work there to have an emergency back up that I can also use to help fellow boaters.
4) Checked the access hatch and tray seals... 99% functional so I am going to wait for the off season to strip the old and replace.

Took it out yesterday, ran it at about 45 MPH for a good hour or so on a choppy/wakey Lake Travis... top of the plugs were dry, not much if any water in the bilge... I am thinking what did make it back was just residual from other parts of the boat (here's to hoping and I don't have other issues) I am still going to have the mechanic at the dry stack give it a once over for the hell of it.

Based on the EZ Locks being in there and the plugs not having water on top of them after yesterday, I think I will forego the nerf footballs and leave those for the Longhorns to learn how to play some offense before the Red River game next week.

Thanks for all of the input and help.

Click to expand...

Good for you now that you have a bilge alarm, and you have put on my EZ locks time tested and made at the request of Yamaha jet boat owners years ago. Remember this the lock will actually tell you that the plug tried to release and it saved you from a blowout . When the inner parts fail the t handle tries to go up and the locks prevent that but when you try to remove the lock it will not release until you reset the T handle and free up the lock ends, I mentioned that in the instructions and in a video. Excellent investment for your model year 2000 to 2016 Yamaha jet boat Only $49.95 for a twin engine set with free domestic shipping included anything else seems like a fools errand.
Here are a couple videos for understanding the EZ locks and

Sounds like you have belt, suspenders and braces yet to come. That is very my style. I think you are safe leaving the nerf equipment to UT...

The answer to your question of how much water can come in if the cover blows… it won’t stop until the engine stops. My clean out lid blew off but I didn’t catch it until the water was at the top of the engines. EZ locks and an alarm are the way to go. Personally, I would take my boat out again without the locks. I suggest tugging on the t handle three hard times to make sure the plug is secure before inserting the clips of the EZ locks. @tdonoughue ‘s suggestion of ensuring the hose clamps are secure on the clean out tube is spot on. If you take the lid off under the hatch, you’ll see the tube. It needs to be seated at the top and the bottom with a hose clamp at the rim of each one. If it slid away from the ends, the shape of the tube can get manipulated when the hole cover got lodged inside the tube, and that’s where water can be forced into the bilge area, which also fills into the engine compartment.