'01 246 8.1 overheating

['01 246 W/8.1GSi]

I've been getting an intermittent alarm beeping for awhile now but not showing an over temp issues. Sometimes I could go out for a ride and no alarm, sometimes it comes on after 30 minutes, sometimes after 5 minutes and other times right away. The last time it go hot and went into limp mood. So I replaced impeller and t-stat today but still overheating. All the blades were gone on impeller. Captains Call on there’s no water coming out through hull exhaust. I pulled the lower hose on the pump and blew in one of the hoses from the T-sat and a lot of blades came out, but no where else. I ran a hose out to my boat and ran water through every hose I could find and or get to. There appears to be no obstructions in the engine. I ran the water through the top hose at the pump and water was coming out the lower drive, but slowly. While doing this I put lower unit in the water and when I removed the water hose, water continued to come out the hose by the pump. I think it was siphoning from the lake and did not stop until I raised the hose up. So it there appears there’s no blockage there. But when I hooked up the muffs there was no flow at all from any of the hoses. I hooked everything back up and ran the engine with the muffs on and no flow any where.

[Big Block Power]

There is a power steering cooler on the starboard side rear of the engine. The cool fuel pump, the manifolds, yep plenty of spots for the pieces to get stuck

[AsLan7]

I've been getting an intermittent alarm beeping for awhile now but not showing an over temp issues. Sometimes I could go out for a ride and no alarm, sometimes it comes on after 30 minutes, sometimes after 5 minutes and other times right away. The last time it go hot and went into limp mood. So I replaced impeller and t-stat today but still overheating. All the blades were gone on impeller. Captains Call on there’s no water coming out through hull exhaust. I pulled the lower hose on the pump and blew in one of the hoses from the T-sat and a lot of blades came out, but no where else. I ran a hose out to my boat and ran water through every hose I could find and or get to. There appears to be no obstructions in the engine. I ran the water through the top hose at the pump and water was coming out the lower drive, but slowly. While doing this I put lower unit in the water and when I removed the water hose, water continued to come out the hose by the pump. I think it was siphoning from the lake and did not stop until I raised the hose up. So it there appears there’s no blockage there. But when I hooked up the muffs there was no flow at all from any of the hoses. I hooked everything back up and ran the engine with the muffs on and no flow any where.

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Hello 01. Welcome to the CobaltChat forum. So glad you found us!

Sorry to hear about your overheating woes. You may be able to glean some information from this post.

Any pics of your 246? We love pics here. Feel free to start a new thread with how you got into your precious Cobalt. Only if you have the time of course.

Again, welcome aboard mate.

.

['01 246 W/8.1GSi]

I've been getting an intermittent alarm beeping for awhile now but not showing an over temp issues. Sometimes I could go out for a ride and no alarm, sometimes it comes on after 30 minutes, sometimes after 5 minutes and other times right away. The last time it go hot and went into limp mood. So I replaced impeller and t-stat today but still overheating. All the blades were gone on impeller. Captains Call on there’s no water coming out through hull exhaust. I pulled the lower hose on the pump and blew in one of the hoses from the T-sat and a lot of blades came out, but no where else. I ran a hose out to my boat and ran water through every hose I could find and or get to. There appears to be no obstructions in the engine. I ran the water through the top hose at the pump and water was coming out the lower drive, but slowly. While doing this I put lower unit in the water and when I removed the water hose, water continued to come out the hose by the pump. I think it was siphoning from the lake and did not stop until I raised the hose up. So it there appears there’s no blockage there. But when I hooked up the muffs there was no flow at all from any of the hoses. I hooked everything back up and ran the engine with the muffs on and no flow any where.

This weekend I'm planning on using a hose to supply water directly to the pump housing. With the engine running if there's no over heating and getting water out the exhaust then I would think the blockage is in the lower unit.
Any thoughts?

[Big Block Power]

If your impeller came apart your blockage is after that not before that.

['01 246 W/8.1GSi]

If your impeller came apart your blockage is after that not before that.

I get that but everywhere else appears to be clear.

['01 246 W/8.1GSi]

There is a power steering cooler on the starboard side rear of the engine. The cool fuel pump, the manifolds, yep plenty of spots for the pieces to get stuck

According to the serial number it does not have a power steering cooler.

[SAB220]

You may want to used compressed air, remove hoses and worst case remove freeze (Welsh) plugs. I don't want to damage what's there but what about a flex cable? BTW - I clean shower house drains with wet/dry vacuum.

[akorcovelos]

Have you confirmed the engine water pump is working?