Shoelessjoe
Recruit
- Joined
- Jun 26, 2017
- Messages
- 1
I have a 2003 5.0L V8 Mercruiser that is overheating. I have spent hours trying to run this down. First a little about the boat and motor. I have a Bayliner 245 Ciera. It has an Alpha drive with a Bravo pump below the motor. It is a fresh water cooled system with an Orca heat exchanger. From what I hear, my system is unusual. I have an impeller on the alpha drive that goes to a wye. From the wye it goes to a bravo pump. The wye is also connected to a thru-hull intake. That bravo pump then feeds the heat exchanger. The raw water moves through the H/E and back out the risers and into the sea.
The closed system circulates through the engine, the manifolds, the hot water heater and the cabin heater.
Here is what is going on and what I have done to date.
I have had the boat for about 5 years. I didn't start getting alarms and high temps on the temp gauge until early last summer. The boat always ran at 175F which, from what I've read, is right in the wheelhouse. Last year the temp started to creep up 180-185 and I would get an occasional high temp alarm. It seemed to happen most often when I was at cruising speed and slowed to an idle. I discovered a bad impeller in the bravo drive, replaced it, cleaned the rubber out of the H/E, and that seemed to do the trick. After taking it out of mothballs this spring the problem is worse. It now gets hot with the ears on at the washdown rack. (I keep it in drystack). It will run over 190 and the alarm comes on. I am getting what appears to be good water flow on the raw water system. You can see water coming out of the sterndrive in normal amounts. The risers and elbows are cool to the touch.
I have replace the thermostat. 160F. I opened up the Heat exchanger and cleaned what little debri was in there. Verified water flow. I have warm water running through the closed system lines to the hot water heater and the cabin heater so that tells me my water pump is working. I am at a loss. Has anyone else run into this?
The closed system circulates through the engine, the manifolds, the hot water heater and the cabin heater.
Here is what is going on and what I have done to date.
I have had the boat for about 5 years. I didn't start getting alarms and high temps on the temp gauge until early last summer. The boat always ran at 175F which, from what I've read, is right in the wheelhouse. Last year the temp started to creep up 180-185 and I would get an occasional high temp alarm. It seemed to happen most often when I was at cruising speed and slowed to an idle. I discovered a bad impeller in the bravo drive, replaced it, cleaned the rubber out of the H/E, and that seemed to do the trick. After taking it out of mothballs this spring the problem is worse. It now gets hot with the ears on at the washdown rack. (I keep it in drystack). It will run over 190 and the alarm comes on. I am getting what appears to be good water flow on the raw water system. You can see water coming out of the sterndrive in normal amounts. The risers and elbows are cool to the touch.
I have replace the thermostat. 160F. I opened up the Heat exchanger and cleaned what little debri was in there. Verified water flow. I have warm water running through the closed system lines to the hot water heater and the cabin heater so that tells me my water pump is working. I am at a loss. Has anyone else run into this?
