Those things have been very reliable. But like all motors they are subject to various kinds of failures. I know one guy that religiously cranks his motor at the ramp _before_ launching it. And every time I help him change his water pump impeller, I point out “Look at this, it is a year old and melted/deformed…” And he wont stop doing it. Others run em thru mud or sand, when they are intended to be run thru water. You can pick up trash and clog a thermostat, a poppet valve, etc. Friend complained about a speedo problem on a non-verado. I told him he probably hit a piece of dead wood floating on the river, and that it probably impacted into the pitot opening. He brought it by last weekend and when I looked I thought “thats not wood”. My 1/16″ drill bit revealed that it was mud. And the lower water pickups were also packed with mud. Apparently in running in some of the low water levels around here, the level was a foot lower than he thought… But in general, I know 4 people that have been running those big beasts for a couple of years, and they seem to just keep running quietly, so long as you change the oil as recommended and dont get crazy.. I am not sure what is normal behavior for the things. Many motors run a bit hot at idle or slow speeds, but once you get the water flowing usually not.2008 Pantera Classic2014 Mercury Pro XS 200
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