2006 GTX Overheating, Good cooling flow

[wrighthm]

Hi team; I have a 2006 Seadoo GTX 185HP (Supercharged). I am getting an overheating after running. To check this I have removed jet unit and checked the open circuit cooling intake and correct fitment of RED flow restrictor. I then went inside and checked the hose to the front of manifold. I then blew through manifold and could feel air at hose flush port, If I squeezed that hose the air blows right through to exhaust outlet. Therefore no blockage in open loop system. The only part I am not sure of is the hose flush line has no one way valve so when under normal operation closed water is taken in from jet unit flows to front of manifolds, leaves manifold through two small hoses to the stainless inlet pipe and here it has two options, exit via flushing port or continue through stainless pipe to small holes where it joins exhaust gas. I was thinking the flush should be one way so that in normal operation all manifold cooling passes to the exhaust. When I flush with hose most water exits the ski through the intake of the jet unit (normal closed cooling inlet) with the balance coming from exhaust port. Again confirms all OK but as on flushing hose removes the possible back flow issue.

On the closed cooling side when running the expansion tank warms up especially the little upper return hose and the ride plate gets hot too. Its never ejected any coolant from this system.

I guess I am looking at 3 possible issues:-

1. the hose flush should have a one way valve and not enough water goes to exhaust in normal operation as it exits the flush line
2. the exhaust temp sensor is working but not reading correctly, if I unplug i get an alarm
3. the little holes in the stainless exhaust exit pipe may be partially blocked

Any help anybody has with this would be much appreciated, thankyou

 

[ski-d00]

1. Not correct it's an open system with no check valves.
2. Temp senders are very reliable but simple to test and swap.
3. Simple to pull the j-pipe and clean system. Check flow through manifold while you're there.

 

[skiasylum]

1.
Can someone explain why there is no cap needed on the flush port? There are caps on the drain ports. The flush port allows pressurized water into the exhaust system when back flushing but somehow does not allow water out of the port when pressurized water from the jet pump is forcing water through the exhaust system for exhaust cooling. Water finally exits out the exhaust port to the lake or ocean where it came from and that is why the system is considered open.

 

[ski-d00]

The reason there is no cap on the flush port is because it is an integral part of the open cooling system where it will actually let air into the system. If you plug the flush port, it will also cause an overheat situation at full throttle. Without the venting from the pressurized system, water flow is reduced.

 

[wrighthm]

Thanks everybody. I did find in the shop manual a picture showing water flow from the front of the manifold through the J pipe and also exiting the J pipe to the flush inlet. Arrow showing that becomes a discharge. I'm hoping my case is blockage in the J pipe as the manifold was replaced last year due to the poor storage and corrosion. I hope some debri has blocked the small holes in the J pipe and thats the overheating issue. If not im still in teh dark.

Does anybody know a couple of ohm values for the exhaust sender at say ambient and boiling, so I can verify it

 

[Kenzeon]

Were you able to fix the issue? , running in to the same problem with my 2005 rxt. It runs well but if I go above 7000 rpm it will give me H.Temp error.

 

[wrighthm]

Hi Kenzon; We never got to the bottom of this and the ski remains unusable. We replaced both temperature sensors and the wiring loom just in case. We then went on for new fuel injectors in case it was combustion related. All the cooling was flushed and all paths clear. Our last option will be to pull the engine and verify the cooling pump is OK. To be honest that is where you should start as we are now thinking the issue is a transference of the closed circuit not working optimally. Good luck

 

[Kenzeon]

Hey Wrighthm , I'm only experiencing this issue when I'm WOT. I would like to start with the basics, attached is my open loop cooler routing with numbers, can you explain to me which hoses based on the number I need to back flush. I have a 2005 RXT Sea Doo.

 

[ski-d00]

The most problems I see are with the j-pipe as far as overheating goes especially at WOT. It has 3 small holes at the exit that clog easily with sand. It should be removed and cleaned and tested for flow. You can also check flow through the exhaust manifold at this time that also can get sand clogs as well.

 

[Kenzeon]

The most problems I see are with the j-pipe as far as overheating goes especially at WOT. It has 3 small holes at the exit that clog easily with sand. It should be removed and cleaned and tested for flow. You can also check flow through the exhaust manifold at this time that also can get sand clogs as well.

Just to be clear, clean the J-pipe and back flow through Hose number 4 (in this case) to check the exhaust manifold flow. I'm only getting the issue at WOT.

 

[ski-d00]

I usually disconnect the hose at the intercooler, bigger hose to put garden hose to, and flush the normal flow direction and watch how much comes out of 4 and 6. Then plug 4 and watch all flow come out of 6 and vice versa. It should flow very freely.

Remove j-pipe and flush every which way and make sure you get fast equal flow out of the 3 holes. Fairly simple to flush all lines and should only be a 1 hour project.

 

[Kenzeon]

I usually disconnect the hose at the intercooler, bigger hose to put garden hose to, and flush the normal flow direction and watch how much comes out of 4 and 6. Then plug 4 and watch all flow come out of 6 and vice versa. It should flow very freely.

Remove j-pipe and flush every which way and make sure you get fast equal flow out of the 3 holes. Fairly simple to flush all lines and should only be a 1 hour project.

Thank you so much for the clarification, I'll tackle this project on Friday. I'll keep you updated.

 

[wrighthm]

Hey Wrighthm , I'm only experiencing this issue when I'm WOT. I would like to start with the basics, attached is my open loop cooler routing with numbers, can you explain to me which hoses based on the number I need to back flush. I have a 2005 RXT Sea Doo.View attachment 63700

Good morning;

For the open loop this starts at the jet pump and a restrictor, easy to check this is clear. Next the long pipe which passes to the front of the manifold. Make sure the inlet elbow to manifold is not restricted. I did swap a manifold where this was so bady rusted and compleatly blocked. Next to the J pipe and the small wholes in its annulus. Also make sure the J pipe exit boot is installed correctly. After that you have covered all the open loop bases. Good luck.

 

[wrighthm]

And yes the saga is still going but I have a new lead. The J pipe holes are good but the connector to the exhaust has a big lip which may end up stopping the flow. Picture attached. Ill try and get a new coupler tomorrow.

 

[wrighthm]

YEs the problem continues. I have now verified all hoses are fee including J pipe. When ski is in water it can idle and the J pipe is cold. If i remove the manifold inlet a low sea water flow can be observed. Re connected and J pipe cools. If i give the ski some load on trailer J pipe warms up and high temp alarm comes on. If i let idle the J pipe cools down and alarm goes. I've again pulled the jet pup and can see no issues. I again checked flow from jetpump bulkhead inlet right through system. It just seems the jetpumps inlet venture is not providing sufficient flow at load. Any help would be most appreciated.