Heat Exchanger help
I am troubleshooting an overheating problem and need some advice on the heat exchanger and the exhaust elbow. I took my boat out for the first time and it started running hot within 10 minutes of leaving the marina. I was getting water out with the exhaust, however I think it should be more. I've looked at other posts and still have some questions. I've checked the thermostat and the impellors (both on the closed loop side and raw water side) and they are OK. Here's my plan so far:
-Dive over and scrape propeller blades and the raw water intake to remove "critters".
-Run a weak muriatic acid solution (or off the shelf product) into the raw water side of cooling system and flush.
Here is where I need the help. Is there a flush or cleaning procedure for the closed loop side of the heat exchanger? If it needs to come off, how is the exhaust elbow cleaned?
I have a Volvo-Penta MD11C. At the dock, I've had it running both at idle and in forward for >1hr with no overheating.