2003 Excalibur 330 Overheating

[core-rider]

It sounds like to me you have air entering the system somewhere. When running at speed the RPM's are either high enough to overcome it, or the force of the water being pushed into the pick-up causes the leak to not be an issue. Wish I had more info to help, but all I can say is look for loose hoses, strainer connections, etc.

Did this problem just suddenly show up out of nowhere or did you do some kind of maintenance that might have caused the problem? If that's the case I would tart looking at the items you did work on. It's something simple I guarantee.

[Peter Wake]

Hey Jason

The overheating started this season - I winterized the boat in the fall - this spring is started with the intermittent overheating so I replaced the impeller and thermostat etc...

I borrowed a laser thermometer from a buddy - it confirmed that the engine really is up over 200 degrees...that and it went into limp mode....and the one exhaust pipe started to collapse..

On the bright side - I was able to take one of guys on the lake for a ride (temp was fine until I went back to the dock) and he landed a 540 for the first time so that was cool!

Thanks for you help.

Peter

[core-rider]

Hey Jason

The overheating started this season - I winterized the boat in the fall - this spring is started with the intermittent overheating so I replaced the impeller and thermostat etc...

I borrowed a laser thermometer from a buddy - it confirmed that the engine really is up over 200 degrees...that and it went into limp mode....and the one exhaust pipe started to collapse..

On the bright side - I was able to take one of guys on the lake for a ride (temp was fine until I went back to the dock) and he landed a 540 for the first time so that was cool!

Thanks for you help.

Peter

Triple check all your hose connections that were pulled loose during winterization. Like I said, check the o-ring gasket on the strainer. That one gets me almost everytime I remove the strainer to clean it. Make sure there are no hoses that you accidently routed in another way that may have caused them to collapse. Check the strainer for any cracks in the cannister. You said you checked for impeller pieces best you could.... I wonder if taking a few hoses off in certain places and back-flushing the system might dislodge anything you couldn't find?

Again, good luck with it.

[TRDon]

I will again point fingers at the water pump, mine did the exact same time. Did you see if yours was painted black or bare brass?

[WakeSlayer]

Core-rider is right on all suggestions.

You said you used a laser thermometer. Where was it 200+? those things are pinpoint accurate and you can track your whole system temp from intake to exhaust ports. While it is running, follow from the intake thruhull, up the hose, trans cooler, RWP, circ pump, you will know where the water stops flowing, if it ever stops. Do the bucket move after the strainer. Attach a hose, put it in a bucket of water, fill that bucket with your garfen hose and keep it running. Check how much water volume is coming out the exhaust. There are a bunch of ways to track this down.

I think you have air coming in, you just need to track it down.

[tim.muench]

Heat Exchanger?

If your boat has a heat exchanger like mine, it was plugged with remnants of previous impeller disintegration. I was surprised at how much rubber was in mine,. Easily enough to affect cooling flow