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98 GTX LTD running hot

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Grim

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I finally got it in the water about a week or so ago and did a quick run. Only because after about five minutes I checked the tuned pipe and it was hot to the touch (motor too), about a 3 sec hand touch was all I could do. So I brought it back in. I notice the ski wasn't pissing right and found one of the two holes in the back was was partially clogged, the hole connected to the fitting on top of the tuned pipe. Fixed that and brought it back to the water yesterday. Ran it for about 10 or so minutes and noticed it was hot again, about a 4 or 5 second hand touch. The engine was hot too, maybe not as much as tuned pipe but still hotter than I think it should be. I noticed during the run one of the pissing holes is not pissing all the time but sporadic, same one that was clogged. More coming out than not but still sporadic. This is with the motor running least 4K RPMs and more. I think I have a restriction. Here is the diagram I have for this motor. I am going to recheck all hoses since I had to replace them all because they were missing, thanks to a rat.

One thing I noticed, per diagram, is it has one of the CSIs (pissing holes ) is at the front of the hull, mine are both at the rear right under the tiedown point.... did I make a mistake with that? I think the diagram is from a 99, maybe design change?

Also, when the motor is on the garden hose it doesn't get hot, its rather cool. Can anyone tell me the flow when on the garden hose, cant seem to picture it. From what I figure it comes in through the engine water return hose...does it go through the regulator at all?

Another thing, where is the intake hole for the engine water supply hose, can't seem to find it in the back near the pump? Is it under the bottom grate?

Lastly, I have not really done anything with the pressure regulator, could this be causing the overheating?
 

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Heres another thing to check...with hose connected and the ski running,,,take a strong flashlight and look at the top left fitting going into the transom,,,this is the water intake,,,sometimes it will leak at the "o" ring,,,and of course reduce the amount of of cooling water from the lake.
 
Heres another thing to check...with hose connected and the ski running,,,take a strong flashlight and look at the top left fitting going into the transom,,,this is the water intake,,,sometimes it will leak at the "o" ring,,,and of course reduce the amount of of cooling water from the lake.
Thank,
Ill take the hose off and look inside as well. With this thing setting for 9 years that oring could be toast and clogging things up.
 
Heres another thing to check...with hose connected and the ski running,,,take a strong flashlight and look at the top left fitting going into the transom,,,this is the water intake,,,sometimes it will leak at the "o" ring,,,and of course reduce the amount of of cooling water from the lake.
I took the hose off and there isn't an O-ring, its just a nipple, I also check the parts manual and it doesn't show one. I took the supply hose off the engine side and ran water through it, just a cup full, no restrictions through the hull area. One thing about the diagram I don't understand. Is there two ways to cool the head pipe, I see water coming in from the engine side, I assume it goes through the exhaust manifold into the head pipe and out the bottom of head pipe, and there is water coming from the regulator cooling the head pipe. Am I missing something here, why two sources? I need to understand this so I can figure out where my restrictions may be.
Also, should the water coming out the back of ski from the hose at top of the diagram have a constant flow, or can it be sporadic? Is the flow to this hose regulated by the water regulator?
 
Update: I am systematically checking for blockage.
I took both the out lines off from the connection at the hull, both lines run strong out the hoses (the two small top hoses coming off the head pipe). Hooked them back up and they are running strong out the back of the ski.
Took the line coming for the regulator to the heap pipe off, at the head pipe. The stream of water is ok but not strong, any ideas if this is suppose to be a strong flow? I also noticed some air pressure out the head pipe connection, where I removed the regulator hose. Is this suppose to do that? I would think it would fight against water coming in from the regulator. Or could this be a result of using the garden hose as a water supply?
 
I also got an infrared laser thermometer to check temps on my next ride. Anyone got a good idea what the average temp on these engines should be. Both for the head pipe and the exhaust manifold/cylinder area. I know 187 degrees is where the alarm goes off.
 
Another update: I went to the river again today and ran it, I have new data. The engine doesn't overheat if I stay below 3K RPMs (ish). I notice when I get to around 4K RPMs and above it gets hot on me, I measured the temp at about 201 at exhaust manifold and slightly lower at head pipe. When I returned and rode it for about 5 mins in no wake zone, it cooled down to 115 or so. This is weird. It makes me think it is something with the regulator. That device changes water flow as you increase RPMs. Any have any ideas based off this new data?

Anyone know how the red cap adjustment on the regulator works, the book says it is set at factory but maybe mine is off?

FYI, I have taken the regulator apart and inspected it, no issues. I also verified water was comes out of it to the head pipe with the ski running on a garden hose.
 
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