I bought my 88 Wellcraft Nova 23XL last season. She ran a little hot, but I primarily operate in under 10' of water, so I chalked it up to a bad impeller and hot water.
Last fall, I discovered that the PO had removed the t-stat in order to maks an obviously overheating engine. I hit the usual suspects, cleaned out the elbows, with some ingenuity and compressed air, added a thermostat, and generally poked around.
Two weeks ago, the temp shot up while running WOT down the creek. Typically it would crawl up at WOT, but that day was different. I got her into dock, without blowing the engine, and hauled her home.
I was convinced that I had sucked up some hydrilla or sand, so I picked up a new impeller. I discovered the actual problem while loosening the lower unit. My water tube (lower to gimbal) had cracked in numerous places, and even had a pencil lead sized hole in it
Yesterday I pulled the drive unit, checked the check balls, pulled all motor-side hoses to check for obstructions, and I am going to pull the bell housing this evening. I am going to do the drive and shift cable bellows, as well as the gimble bearing, at the same time. I have through hull exhaust, but it used to be a standard through drive exhaust. I am going to see how much of a bear it would be to get the block off plate installed inside the transom to eliminate the need for the exhaust bellows.
Hopefully this was the root of my overheating issues. I am going to test impeller flow once I get the whole shebang back together (which will be Friday or the wife will kill me), and have at it!
Last fall, I discovered that the PO had removed the t-stat in order to maks an obviously overheating engine. I hit the usual suspects, cleaned out the elbows, with some ingenuity and compressed air, added a thermostat, and generally poked around.
Two weeks ago, the temp shot up while running WOT down the creek. Typically it would crawl up at WOT, but that day was different. I got her into dock, without blowing the engine, and hauled her home.
I was convinced that I had sucked up some hydrilla or sand, so I picked up a new impeller. I discovered the actual problem while loosening the lower unit. My water tube (lower to gimbal) had cracked in numerous places, and even had a pencil lead sized hole in it
Yesterday I pulled the drive unit, checked the check balls, pulled all motor-side hoses to check for obstructions, and I am going to pull the bell housing this evening. I am going to do the drive and shift cable bellows, as well as the gimble bearing, at the same time. I have through hull exhaust, but it used to be a standard through drive exhaust. I am going to see how much of a bear it would be to get the block off plate installed inside the transom to eliminate the need for the exhaust bellows.
Hopefully this was the root of my overheating issues. I am going to test impeller flow once I get the whole shebang back together (which will be Friday or the wife will kill me), and have at it!