Pistol
Well-Known Member
- Messages
- 3
- Reaction score
- 21
- Points
- 62
- Boat Make
- Yamaha
- Year
- 2015
- Boat Model
- SX
- Boat Length
- 24
Hey folks, my 2015 SX240 has been taking on an excessive amount of water since new. I’ve seen some great threads on this issue but have found a cause on my boat I haven’t seen before so I’m posting this for all those who have exhausted the “usual suspects”. I had the extended warranty on this boat and took it to Charleston Powersports twice for this issue; the first time they said the jet housings were leaking and resealed them and the second time they said several clamps in the exhaust compartment were rusted out which they replaced. Neither repair fixed the problem. With the engines operating above 6,000 RPMs water was going into the bilge faster than the pump could scavenge it. I realized that running at speed for longer than 20 min led to water entering the engine compartment around the high pressure cooling line (mainly on the port side) which meant the exhaust compartment was filling at least to that level and the bilge pump couldn’t keep up with it. So I removed the large access panel in the clean out compartment and started going through all the exhaust connections and clamps. Everything appeared correct and intact. However I could see water literally spraying into the compartment with the port engine running. It was coming from the resonator on that side. The clamps and exhaust hoses were all intact, so I removed the resonator which first required removing the clean out tube, water block and associated exhaust hoses. With the resonator removed the problem was obvious. See the first image which shows the inlet side of the resonator collapsed on itself.
The high pressure cooling water coming out of the exhaust manifold and then the water block was entering the exhaust compartment under this kink in the resonator which was invisible with the hose attached. FYI, the resonator is nothing more than a hollow plastic “jug” about the thickness of the windshield washer fluid reservoir in a car. The inlet connects to the water block and the outlet connects to the elbow fitting that comprises the exhaust port. Not sure why this thing runs about $80. Anyway the part is not available for 2015 and later (although it is the same resonator going on current production boats) so I had to figure out a way to try and repair it. Heat gun in hand, I was scouring my shop for something round to reform the inlet tube when I noticed the metal travel mug of coffee in my other hand. Yep, perfect fit for the undamaged side. Judicious application of heat and some prodding with my travel mug reformed the resonator perfectly. See next image:
After reinstalling the exhaust components I have run the boat repeatedly and the bilge is bone dry. The auto bilge no longer runs continuously at speed. It cycles on for a split second every two minutes (auto function) and immediately turns off again. I no longer have any water entering the exhaust compartment or engine compartment, even after 10 hours on the water - Wow!
Lessons learned: First, this is my 7th season on the water with this boat, and it’s obvious to me that from watching water drain from the bilge for 5 minutes up to this point that this defect has existed since the boat was manufactured. So don’t assume the boat is correct even when bought new. Second, the dealer won’t always find the problem. Charleston Powersports missed this twice, but to be fair this defect was not easy to find. The resonators on these boats are tucked about as far up and out of the way as possible. Third, USE the shop manual. I was surprised to find that the band clamps in the exhaust compartment only need to be hand tight to seal the system. Someone had to WAY over tighten the clamps on this resonator to cause that damage. Finally, in the process of doing this repair I found that the silicone sealant between the cleanout tubes and the plug housings had completely failed, allowing some water to enter the bilge around the plugs if they weren’t perfectly watertight. So while my resonator was the vast majority of the problem it wasn’t the only place water was getting to the bilge. So in addition to the resonator fix I rebuilt the plugs using the kit that contains the new rubber gasket and plastic base. Super easy. The plugs don’t let any water in and if they do, it no longer finds it’s way into the bilge.
Hope this helps!
The high pressure cooling water coming out of the exhaust manifold and then the water block was entering the exhaust compartment under this kink in the resonator which was invisible with the hose attached. FYI, the resonator is nothing more than a hollow plastic “jug” about the thickness of the windshield washer fluid reservoir in a car. The inlet connects to the water block and the outlet connects to the elbow fitting that comprises the exhaust port. Not sure why this thing runs about $80. Anyway the part is not available for 2015 and later (although it is the same resonator going on current production boats) so I had to figure out a way to try and repair it. Heat gun in hand, I was scouring my shop for something round to reform the inlet tube when I noticed the metal travel mug of coffee in my other hand. Yep, perfect fit for the undamaged side. Judicious application of heat and some prodding with my travel mug reformed the resonator perfectly. See next image:
After reinstalling the exhaust components I have run the boat repeatedly and the bilge is bone dry. The auto bilge no longer runs continuously at speed. It cycles on for a split second every two minutes (auto function) and immediately turns off again. I no longer have any water entering the exhaust compartment or engine compartment, even after 10 hours on the water - Wow!
Lessons learned: First, this is my 7th season on the water with this boat, and it’s obvious to me that from watching water drain from the bilge for 5 minutes up to this point that this defect has existed since the boat was manufactured. So don’t assume the boat is correct even when bought new. Second, the dealer won’t always find the problem. Charleston Powersports missed this twice, but to be fair this defect was not easy to find. The resonators on these boats are tucked about as far up and out of the way as possible. Third, USE the shop manual. I was surprised to find that the band clamps in the exhaust compartment only need to be hand tight to seal the system. Someone had to WAY over tighten the clamps on this resonator to cause that damage. Finally, in the process of doing this repair I found that the silicone sealant between the cleanout tubes and the plug housings had completely failed, allowing some water to enter the bilge around the plugs if they weren’t perfectly watertight. So while my resonator was the vast majority of the problem it wasn’t the only place water was getting to the bilge. So in addition to the resonator fix I rebuilt the plugs using the kit that contains the new rubber gasket and plastic base. Super easy. The plugs don’t let any water in and if they do, it no longer finds it’s way into the bilge.
Hope this helps!
