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Warm water from Bilge.....on the water need some help.

Possibly. Interface isn't threaded or slotted like those pictured in your link. The hourglass shape does match Dremels design for QD tool attachment though.
It might be some type of backing lock that twists on.
 
Since this appears to happen only at WOT, it could be the water escaping through the clean-out plug seeping into your bilge via access port sleeve or opened grooves/cracks between the screwed downed piece in your rear hatch.

Maybe test by plugging the drain hole in the rear hatch and fill up that area full of water to see if water drains down into the bilge or not.

I believe most of the water from my bilge leaks somewhere through the rear hatch. If I take the boat to a 5MPH creek, I get no water in the bilge vs. taking it to a big lake and WOT for miles.
 
Get some hearing protection, ear plugs or muffs, and spend a little time in there at WOT with a flashlight.
 
@2kwik4u Did you find the source of the problem?
I have not found a definite solution. I have some suspicions though.

Had the boat out for another 3 or 4 visits to the water since I posted. This past Sunday we went a bout 20 miles up river (and 20 miles back). The bilge ran once on that trip, but the water was "warm" not hot. As if it had just been sitting in the boat for awhile, or there was additional water in the bilge that hot water mixed with. It was definitely warmer than the river water, but wasn't HOT like it just came out of the engine cooling loop. The majority of that 20 miles though was spent ~6,500rpm or so, not at WOT.

Saturday I had the boat out doing watersports with a group of teenagers. I had some bilge action then as well, but again it was just luke warm it wasn't hot. That involved a lot of short WOT bursts to get the riders up, then settling down in the 6,200rpm range for the pull. Probably repeated this 50 times in 2hrs.

My suspicion at this point is two fold. The first is the inability to get the bilge completely dry. The second is a leaky rear cleanout tray.

When I first made this post, the boat had sat in the garage for 3 weeks straight. Any water that was in the bilge would have heated up significantly sitting in there. Our garage isn't insulated, has terrible ventilation, and the metal door faces west, so it gets the evening sun. 3 sides are bricked on the outside as well, so all the bricks heat leaks into the garage (it's a winter project to improve that insulation issue). I suspect I had water in the bilge that had heated up significantly, and then was rushed to the back during the outing. I'm not 100% convinced of this, as the water in my first post as HOT, like hotter than comes out of my faucet at home hot. My lack of recent problems has me thinking it's not a cooling system leak though.

I also noticed on Saturday while checking the bilge, that I had some residual water in the cleanout tray area, and it was leaking right through the screw holes. When I "sealed" the rear tray area earlier this year I didn't remove the screws, or the access cover, I just ran a bead of silicone all the way around the edges. Looked nice, and stopped a good portion of the water intrusion. I see now that I need to remove each screw, and seal under them as well. I might just pull the access cover and start over again from scratch on this honestly.

Overall it doesn't appear the engine is in any immediate danger. I've put another 10-12hrs on it since this first event, and I've not had a single problem with the engine. Even working it hard pulling 3 large teenage boys on a tube didn't seem to make a difference. I continue to get good flow from the outlet on the side of the boat, indicating I have good cooling water flow through the engine, and I had no hard starting or rough idle that usually accompanies a "vapor lock" condition from running it hard, then shutting it off and attempting a restart in short procession. The bilge isn't' running a lot when it does run. Maybe 10-15 seconds. Just long enough that I can see it, but not long enough to move back and get my hand in the flow to feel the temperature.

It bugs me to leave the source unknown, but at the same time it doesn't seem to be a problem to anyone/anything but me. Very frustrating honestly.
 
I have not found a definite solution. I have some suspicions though.
I don't get how the water is getting in from the cleanout area? Isn't there a drain for the "wet storage" area?
 
I don't get how the water is getting in from the cleanout area? Isn't there a drain for the "wet storage" area?

There are 3 ways that water can get into the rear cleanout tray. I took some videos last summer (maybe the summer before), but they got lost on an old phone. I'll try to take some more when I get a chance. Since the baby has been here it's been tough to find time on the water to do that kind of experimenting. What I did was tape down the hatch switch, and then mounted a phone to watch the cleanout tray area with the hatch open. Here's what I found for water intrusion to the rear tray;
  • From the cleanout plug not being installed properly, or leaking past the seal.
    • This isn't very likely. I saw no evidence in my videos of my plug leaking. No water coming up from the cleanout plug itself even at sustained WOT operation. I would expect a drop in speed and thrust if this was the case as well. Those that have left the plug out, typically notice immediately. Perhaps a leak wouldn't be as dramatic, but I suspect it would have shown more prevalent in the videos I took.
  • From the around the sides of the hatch
    • With two people on board and purposeful attempts to get water over the second step on the swim platform I couldn't do it. Had 8 people on board doing wake sports (no intentional ballasting) this weekend, and even with a couple really good, "almost got it" start attempts where there was a HUGE wave behind the boat when I came off the throttle, water still never got over the second step. You have to have significant weight beyond people and gear in the boat to get water over that second step. Some of the guys surfing might be able to make it happen when they have 2k lbs of ballast and the rub rail starts under water, but in 3 seasons of use, I've not seen it happen yet.
    • If you do get water on the second step it goes around the hatch seal like it's not even there.
      • My almost 2yr old likes to sit on that upper level and LITERALLY dump buckets of water on himself. He has a little toy bucket and gets the biggest kick out of filling it up, sitting down, and dumping it on his lap. Before I lightly sealed that cleanout tray panel, you could watch the bilge respond to each bucket he dumped. One bucket on the toddler, wait 30-34sec, one bucket from the bilge.
      • Those seals between the hatch and the tray area are NOT great. I think they catch more dirt than they do water, but I leave them there to fight against rattles from vibrations.
  • From the drain "backflowing"
    • This is the main source of water in the cleanout tray IMO. Every time you come off plane, the water rushing in behind the boat pressurizes the drain (the tube that runs from the cleanout tray overboard) in the wring direction. This allows water to "backflow" into the cleanout tray and floods that compartment. I have suspicions that when on plane in heavy waves that every time the stern of the boat comes "down" some small amount of water is forced backwards through that drain.
      • Example 1 - When running around Patoka, it's often VERY wavy due to the shallow and wide nature of the lake. Nowhere for the waves to dissipate to. If I run for more than 10-15min on plane, the cleanout tube between the tray and plug is full of water, and the tray is wet just about everywhere. Now I didn't come off plane to force the water back in there, but I did cross tons of other wakes, and had the stern "bouncing" along the water.
      • Example 2 - We took a trip from Old Hickory Lake to Nashville last summer. 25miles on the Cumberland River. MOST of that time was spent on plane at 30mph or so. Water was DEAD FLAT, like glassy smooth, for the majority of the trip. When we got to the dock in Nashville, I had a look at the cleanout tray, and it was mostly dry, and the tube was only about 1/2 full. I only came off plane maybe 2-3 times to looks at various sites along the way (saw a deer swim across the river, that was neat), and there was minimal "bouncing" of the stern. Few chances for the drain to "backflow" in those conditions.
Once the water is in the cleanout tray there are 3 ways it can escape (assuming gravity works, and no major splashing).
  • Out of the cleanout plug tube
    • I usually pull the plug a few times per outing to let the water out. It doesn't help, it usually fills right back up, but it makes me feel better. All the water backed up behind the plug drains around the plug and equalizes with the water line on the outside of the hull.
  • Out of the drain
    • The drain works when it's above the waterline, and it's not pressurized "backwards"
    • The drain could stand to be a standard size larger, and have some form of backflow prevention
  • Leak past the tray into the bilge
    • I think the screws and panel in the cleanout tray represent a larger flow rate than the drain does.
    • I sealed around the panel, but not under the screws.
      • If there is enough water in the tray to cover the screws, but NOT cover the manholes, you can open the manhole and WATCH the water drip in past the screws.
      • They're small drips, but there is a lot of them and they are pretty constant, representing an appreciable amount of water.
Overall this is just not a well thought out system, and the problem is compounded with poor craftsmanship from the factory. I'm considering adding a "block flow panel" to the thru-hull on that drain, similar to what is covering the scupper drain to prevent backflow from happening as often. I'll also be removing and sealing the the screws on the rear tray in the near future.

As much as I love my boat, this random water intrusion B.S. almost makes me want to move to another manufacturer. I bought almost the least expensive boat Yamaha makes, and I get that it's a value model in a value brand, but WOW there are all kinds of little random things like this that make the ownership experience less than stellar. Being in manufacturing, they are all SIMPLE things that could be fixed with some revised processes and training in the factory. Would cost them pennies per boat to remedy, and are mostly attention to detail items from the manufacturing process. A few small design tweaks here or there and I think they could compete much better above their price class.........but that's a whole subject for another thread.

Leftover from manufacturing...?
Yea I think so
 
Yeah best practices are to scuff before you bond any parts and there are alot of sharp bits that need knocked down as well somebody probably just forgot to pick it up. I recognized it because we use the same brand at the shop where I work
 
OK.....I'm reviving this thread.

Took the boat out yesterday for the first time this season. Had a decent, but short, day on the water with the wife. Water temp was in the low 70's as best I can tell, and the air temp was in the high 60's. We putted around the lake, and did some speed testing. It was overcast, and too cool to get in the water ourselves. ZERO watersports, but several high RPM stints to test a few other things.

When I pulled the boat up the ramp, and opened the plugs, I got several GALLONS of HOT water from the bilge. It was obviously warmer than the lake water, and was a significant amount. I'm going to say it took the better part of 2 minutes to completely drain the bilge on the ramp, and is WAY more water than should be coming from the bilge after only a few hours on the water with a light load.

When I ran the boat on the hose this spring to make sure it was in good shape for the season, I let it idle for about 10-15 minutes to get warm. I had ZERO water from the bilge in that test. Not a drop. Of course I can't run it at high RPM for any sustained period without a load on the pump, so I wasn't able to get full "pressure" to the engine in terms of cooling system water. SO, it appears to only be a "high pressure" leak somewhere in the boat.

SO......Where do I look? I couldn't find anything in the engine bay that is obviously disconnected or loose. All the hoses appear tight, with good tight clamps on them.

Here's the plan I've come up with......I'm going to remove the rear tray to get a good look at the hoses/fittings back there. First step is a good inspection on all connections. Maybe it's something easy. If that doesn't work, Then I'm going to block off the line (clamp off) coming from the high pressure side of the jet, and run the engine on the garden hose. This should prevent any "backflow" or pressure loss going through that side of the line. This will raise the pressure in the system to whatever is coming out of the hose, and not just whatever flow happens to go that direction. With the hatch open (i'll have to block off the safety switch), I'll run the engine and look for leaks again. Hopefully this time something will appear and I'll be able to repair whatever has gone awry in the cooling system.

Anyone have a better plan, or another idea?
 
Sounds like you have a good plan, just be careful with the tray open & running it. My guess is either a clamp broke & the line is still on, just leaking or you have a split in one of the coolant lines. Keep us informed on what you find.
 
Looking at this schematic......Boy there sure are a LOT of clamps back there in this area.


I'm assuming all of the exhaust at this point has water mixed in with it, and is a potential source of leakage of warm/hot water into the bilge?!?!

Second question......Anyone know what the max water pressure the system can handle is? I'm considering putting a gauge on the line to measure what I get off the hose, and leaving the gauge in place to watch what I get while running. I know a thread has been done on this before, but I can't find it currently, and it was for the older MR-1 engines, not the new 1.8L's.
 
with the inconsistency of the water I tend to think it's not part of the cooling system,

the bilge not kicking on while the boat is on the trailer doesn't surprise me to much, the pitch of the boat and the trailer can be that the water would pool somewhere besides the bilge area.

I've had days where I get 4 minutes of water out of transom plug but I'm on a steep incline at the ramp, I think how is all that water settling forward and not getting to the bilge,

also don't forget rub rails and pop up boat cleats let water in also,

I think this is just going to be one of those slow test/observations to figure it out,

I would start with removing the cleanout hatch to get a good view of what's going on, I may even run the boat in the water without it (being very cautious of the dangerous nature of having the hatch open, don't put your head over the cleanout plugs) to watch what's going on,

Before you put it in the water next time go to steep area to make sure the transom is clear to start with,
 
with the inconsistency of the water I tend to think it's not part of the cooling system,

the bilge not kicking on while the boat is on the trailer doesn't surprise me to much, the pitch of the boat and the trailer can be that the water would pool somewhere besides the bilge area.

I've had days where I get 4 minutes of water out of transom plug but I'm on a steep incline at the ramp, I think how is all that water settling forward and not getting to the bilge,

also don't forget rub rails and pop up boat cleats let water in also,

I think this is just going to be one of those slow test/observations to figure it out,

I would start with removing the cleanout hatch to get a good view of what's going on, I may even run the boat in the water without it (being very cautious of the dangerous nature of having the hatch open, don't put your head over the cleanout plugs) to watch what's going on,

Before you put it in the water next time go to steep area to make sure the transom is clear to start with,

I'm like 99% convinced it's from the cooling system.

Boat was in the garage except for a single day this spring where I cleaned it out. The driveway is sloped almost as much as our local ramp, and I always make sure the water clears from under the ski locker there. I left the plugs out while in the driveway to make sure anything in the bilge got out.

I also had the boat "nose up" before launching this time.

The other part is this water was WARM to HOT. Like bathwater hot. We haven't had temps over 80 since last summer this year. Water was clearly warmer than that when it was draining. I would say water was easily 85-90 degrees, seriously, bath water temps.

I do think I'm going to end up running it with the hatch open (and possibly the tray out) in the water at some point if I can't find the leak in the driveway. It's just not overtly obvious where it's coming from, and you're exactly right. LOTS of observation and testing to find it.

And we have 3 days on the water scheduled for this weekend....WEEEEEE
 
I'm like 99% convinced it's from the cooling system.

and I would normally agree with you but if it was a cooling system you'd have had this issue every time you took the boat out, so unless you're just not noticing the bilge running or getting more water out your transom plug it's got to be a sometimes issue,

I don't know, wish I was closer to come by help,



.
 
Do you think a pilot water hose from exhaust got disconnected inside? Possibly where it exits the hull?
 
You will know the source of the water when you find it, and not before. Don't worry too much about "guessing" where it is, but instead open your eyes (and maybe the hatch?) to try to find out. It could be any hose fitting or a small seep in the tray, or the bumper seal in the rear. If you open the engine at speed and don't see it, that's a big clue it comes from elsewhere. You will find it when you see it. Once you get enough water that it touches the engine, the water warms up quick.

I would take the rear cover off while on the dock and rev it up to 2500 or so for a couple of minutes while all is well tied off. Open eyes and ears for the ingress source. If no water found after 5 minutes...it's probably not engine related, and you can look at any clamps around the clean out plugs, seams around the back of the boat, etc.

Edit: I reread my message and my open your eyes expression could be read as condescending, it is not meant to be. I intended it to communicate an action that will help as alternative to trying to worry too much ahead of time on where the water is coming from, and meant to signify "looking for the problem as best you can". I hope that intention made it through. In brief... it's not important to guess ahead of time where it comes from, but instead to ID all places it could come from, and then check them all.

Best of Luck!
 
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and I would normally agree with you but if it was a cooling system you'd have had this issue every time you took the boat out, so unless you're just not noticing the bilge running or getting more water out your transom plug it's got to be a sometimes issue,

I don't know, wish I was closer to come by help,



.

I think its happening each time out, but to varying degrees depending on how much time I spend in the upper rev range. My suspicion is that it's a high pressure only leak, and only happens up around 6.5k + in the rev range.

We know from that other thread (I really have to track that down), that cooling water pressure is directly tied to engine speed, due to how the jet pump works, and the cooling water being pulled off the high pressure side of the pump.....SO, I think that's the case here......I think.....

Either way, I'm in for some troubleshooting. Been needing to reseal my rear tray anyway. Might as well get that knocked out at the same time right?
 
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