Sudden Overheat

[MaineDR]

I was out on the lake this weekend when I looked down and noticed the temp gauge soaring! It was around 200+ and ran up to about 220-230 after I killed the engine. I just bought the boat this year and hadn't gotten around to checking the impeller. I started looking everything over and found the strainer was a little loose. I didn't think this could have been the problem, but pulled it off and put it back on. Idled around a little bit and the temp slowly went back down. Could this have been the problem? Anyone else had this happen?

My second question on the subject is how hot should this thing be running? It is a 2000 SAN with GT-40. My dad has an '02 with the Excaliber that normally runs in the 140-160 range. I noticed when I bought it that the temp was around 170 which is at the upper end of the range the manual give (140-170 deg F). Is there something I can do to regulate this down a little more? Different thermostat?

[MaineDR]

Forgot to mention I pulled the impeller after this and it was in decent shape. Could stand to be replaced, but seems functional.

[JT96SS]

My 96 Super Sport with GT-40 run about 160 and holds pretty steady there. not sure but would imagine the water temp would change that +/- 5 degrees. Also on the strainer, if it was leaking a lot your not getting enough water to flow through the motor, could have been the problem.

[a0128]

The GT-40 should run at 160. if you need a new thermostat make sure you use RP026002. There is a 143 degree thermostat but it is for the carb engines. Make sure to get the PCM branded stat. Don't get a no-name or automotive stat.

[MaineDR]

I guess one other thing to note is that the exhaust manifolds are pretty got to the touch. I don't know how hot they are supposed to be, but I've read blockages in the exhaust could be an issue as well with the temp running a little high.

[Paxdad]

If strainer was leaking it will also suck air and cause poor circulation leading to overheating. Your hot risers/ manifold are an indication of poor water flow which could have been caused by the air leak on the strainer or blocked passages.

[Chexi]

As other have said a loose or cross-threaded strainer is very likely the culprit. Engines have been completely ruined by this. My GT40 runs at 160 as well.

[dud77]

Check the strainer for the v-drive cooler. Follow the fluid lines out of the Vdrive. They should connect to a black canister style cooler. Open the water pickup side and you will most likely find trash in the lines. This prevents water from getting to the engine. We have to clean ours out several times per year since we ride rivers.