Engine overheating

[ktm450exc]

I have a 1997 2200v. two weeks ago I had a local dealer replace my impeller change my engine oil and tranny fluid. I took the boat out and ran it for 3 hours without a problem. The next day I launched the boat and I slowly ran over a sandbar. My high engine temp alarm went off as it read 200 deg. I gave the boat gas and drove at 40 mph as the temp went down to 140 / 150 and the alarm went off. When I would cruise at low RPM's the temp would rise so I gave it gas and the temp went down. As the day went on the boat started to heat up around 210 deg as I drove fast and my oil pressure started to rise and I could smell the engine as it got hot so I shut the motor off and waited to be towed in. My mind started to wonder, is it the thermostat, water pump or did the sandbar throw something into my intake. I checked my exhaust to make sure it was clear and water seemed to be circulating through the motor and releasing out the back.

[ktm450exc]

I pulled my freeze plugs and water, small parts of rubber and sand came out. Is it safe to say that my new impeller is toast???

[chpthril]

Pull the new impeller and see what it looks like. I'll bet it's time for a new housing, it's probably eating the impellers.

[hoopykat]

Sounds like running over the sandbar scooped sand into the impeller intake, and the abrasion of the sand chewed up the impeller. Boat ran hot when you drove slow since water flow was reduced, and at higher speeds the water flow was enough to cool the boat. You should replace the impeller, housing and flush the system to remove any remaining sand.

-Mike

[ktm450exc]

Thanks for the replys. I went to the how to section to learn abount replacing the impeller and housing. My boat / engine looks a lot different than the pics. I have a mercruiser 350 EFI scorpion motor. the serial number on the engine is K145183. My boat is a 1997 tige 2200v.

[chpthril]

You did see the "How To" for merc, right!

http://www.tigeowners.com/forum/showthread.php?t=609

[ktm450exc]

The problem was with my impeller. Now I'm taking on a small amount of water when the engine is at high RPM's. I opened up the hatch, put the boat in neutral and ran the motor at 4k RPM's. I removed the side panels and I could not see where the water is coming from. Does the water run through the engine differently when the boat is in neutral?

[mtnsmith]

No, just less pressure. If you don't visibly see a leak then it could be the prop shaft.

[ktm450exc]

I can see where the shaft goes in the boat. If I remember I think I had the dealer install a pack that allows me to tighten the shaft pack.