Re: This is my 1st post here.
WOW John....you have some territory to cover.<br /><br />First....a service manual would be a great help. Usually, OEM's are preferred but some can get along with the generics.....Clymers or Seloc.<br /><br />Get some basic tests' on the engine....these would be compression and spark test. Any compression above 90psi is great but what's more important is that the cylinders are within 10 to 15% of each other. Spark should jump at least a 7/16" gap with a hot lighting like spark.<br /><br />Next, get a temp on the engine. You can do this on muff's in the drive way. Start the engine and let it idle for a while. Large square area on top of the engine just forward of the head, you should be able to set your fingers there for several seconds before pulling them back. This indicates a temp of around 140 to 143*....that's good.<br /><br />If it just stays cold, t-stat is stuck open or not there. Which brings us to the water pump impeller. If you have no ID when it was last changed.....do it now.<br /><br />If you ain't sure when the carb was overhauled last.....do it now. Check your fuel lines and replace any that have become hard. These can lose their grip at connection points and such air.<br /><br />A little test to do next time your in the water, when the engine cuts way down like you posted....pull the plug wires one at a time. If the engine quits, chances are your dropping a cylinder spark. If pulling either plug wire doesn't do much except make it run worse....look else where for the problem.