DT 115 Temp Issue

[Bhack18]

Requesting some insight from the many experience here. I have this 1998 DT 115 for about a year now. It has ran strong with no issues till recently. It started while we were running normal throttle planed out. Then we lost all power and engine wouldn’t even crank to restart. Not sure why loss of all power but grabbed my trolling motor battery and hooked it up. Boat started and we limped back to the ramp. Did couple checks and ended up replacing rectifier and stator. Not that the two are link but it started flashing temp indicator, rev limit, and the check engine indicators when running for more than 4 or 5 minutes. I hadn’t changed the impeller for the year I owned, so I decided replace. This took little longer than expect due to corroded bolts and availability of parts. After getting it together and before starting , I gave the battery a good charge. Motor started right up but after 4 or 5 minutes temp indicator came back on. Tell tell had good stream flowing. I pulled thermostat out to check. Some corrosion but when tested it still functions. So I am little confused on temp indicator going off. Where the water temperature sensor would be there is a sensor plug which seems to have no value other than being a plug. Only other sensor that I see is the cylinder temp sensor. Any help or other troubleshooting I should do would be appreciated.

[Solarman]

When the temp light goes on, what are your rpms, and does the temp light go back off when idling? Does your tell-tale turn to steam when temp light goes on, does tell-tale feel hot, or too hot for your hand?

It's also possible that you could have poor connections at the wiring harness connections?

Post back if you find out what's happening. And if you can answer these questions above.

[Bhack18]

Thanks for reply Solarman. So the engine running with fresh water muffs at about 4 maybe 5 minutes will flash the temp indicator and alarm sound. Engine acts as if it’s going into safe mode but it’s only at idle to begin with. The tell tale remains same stream. It is hot to touch but not enough to burn you. I have ordered new thermostat just in case but like mentioned before it seemed to operate correctly when tested. The one thing that I see that is different on this engine than expect is in place of the actual water temp sensor which would be wired to everything. This engine has the plug. No wires connected. Which would lead me to think the cylinder wall gage is throwing this code. So ultimately not sure where to look next, maybe replace the other sensor for the wall. Thanks

[Bhack18]

So the heating issue was solved.
I replaced thermostat just in case. Started running engine but indicator would go off. I pull thermostat off again and it was dry behind it. So no water flow. I assumed there was blockage somewhere in the system. I pulled the lower off and used a garden hose to force water up through system. I left the thermostat off when doing this. Initially there was almost no water coming out. Used a wire hanger to go up through water tube to see if I could dislodge and debris that may be blocking water flow. I then reapplied the garden hose and had good coming out thermostat hole. I button everything back up and fired it up. No temp light. Good stream coming out tale tell. All seems good now.