2003 GTX 4TEC RUNNING HOT H Temp running lean?

[Drzdude]

So I bought my first seadoo a month ago. 2003 gtx 4 tec non super charged with only 64 hours on it. It sat for over 2 years. So I drained the fuel and purchased refurbished fuel injectors. I changed the oil,oil filter and spark plugs. It statrs Right up and runs great. My first few minutes on the water i got H Temp. So i drained the old antifreeze and flushed out the coolant system. Also pulled the water pump housing and installed a 160 deg thermostat. Back on the water and now I can ride for a little while without having the high temp alarm. Btw no P codes show up when I get the alarm. I will get the alarm if I hold it wide open. So i flushed the coolant again and ran just plain water. Now it runs fine but as you can see its still getting hot up to 206 deg. I pulled the spark plugs today and it looks to be running very lean In my opinion. I don't think I should be running that hot especially with a 160° stat. I don’t see a oxygen sensor in the exhaust so I’m not sure what the ecm uses to monitor the air fuel ratio. I also removed the J pipe and checked the 3 small holes, they were good and i replaced the wear ring. When doing that i flushed all the exhaust cooling lines. Any help will be appreciated.

 

[Digdog]

If all the air is purged and the stat is good then possibly the coolant pump impeller is damaged and not circulating the coolant. My plugs have always been the same color as yours, I have tested and tried everything to get them a little more brown but can't, I think the high octane fuel I use has lots of additives in it. Because of the water cooled exhaust they eliminate the O2 sensor and use manifold temperature and pressure to calculate injection ratio. What I don't understand is you said your machine is non supercharged and yet you are getting supercharged manifold pressure? How is that?

 

[Drzdude]

If all the air is purged and the stat is good then possibly the coolant pump impeller is damaged and not circulating the coolant. My plugs have always been the same color as yours, I have tested and tried everything to get them a little more brown but can't, I think the high octane fuel I use has lots of additives in it. Because of the water cooled exhaust they eliminate the O2 sensor and use manifold temperature and pressure to calculate injection ratio. What I don't understand is you said your machine is non supercharged and yet you are getting supercharged manifold pressure? How is that?

I evacuated the air from the coolant system with an air lift the same way you do for cars. I also questioned the water pump impeller but it looked good when I replaced the thermostat. I included a picture, lmk what you think The manifold pressure is displayed in psi in the candoo software but is actually psia. When the engine is off it reads 14.68 which is atmospheric pressure in my area.

 

[Digdog]

Impeller looks good, are you sure you put the thermostat in the right way? The only thing I can think of is either the plugs are incorrect heat range or the timing is too advanced, or the temperature sensor or the circuit is out of range and sending a bad signal back to the computer. If you have an ohm meter you can test the sensor, I have a accurate bulb thermometer that I leave beside my sensor overnight and do the test then.

 

[Drzdude]

The thermostat is installed correctly. I replaced the engine temp sensor, only because it read 2deg higher than the other sensors at start up. I’ve also confirmed the engine temp with a infrared gun when the alarm comes up. the plugs are the ones the manual calls for. I also flushed out the ride plate with a garden hose, didn’t seem like it was plugged up or anything. You can see why I’m stumped.

 

[Digdog]

The only other things I can think of is the pressure cap is faulty but probably not that, also maybe check the part number on that impeller to see if it's the right one ??? , other than that I'm tapping out. Maybe someone else has some suggestions ?

 

[Drzdude]

Anyone else have any input? Is it normal for engine temp to get over 200 with a 160 thermostat and are my spark plugs too white / lean?