Re: 100hp Johnson Javelin
The hole in your first photo is a drain hole. It will "pee" water when the engine is running and connected to a water source, but isn't intended to be an indicator of water flow. Basically, it is there only to drain your midsection.
The "button" on the back of the lower cowl, is a pee tube or telltale. If you are not getting water flow out of it, you need to trace it back to the block, and look for obstructions.
If you are not seeing any signs of overheat, you are getting water flow though the cooling system. This does not mean that you shouldn't be concerned about your water pump impeller, but at least you are getting water. If you have doubts about the impeller (as in, you can't remember or don't know when it was changed last), change it just be be sure.
Also, the six round holes in your gearcase, just above the cavitation plate, are the main exit points for cooling water in your engine. By hooking up a hose/muff, with the water at just enough pressure to feed the water pump, you can check your cooling system. When you first start the engine with the water supply on. you should see no flow through those holes for about 10 -15 seconds, until the t-stat opens. If you don't see water flow after that period, shut the engine down and start troubleshooting the cooling system.
If you do see water, chances are the problem with the pee tube is confined to it, or the nipple on the powehead. You probaly have a build up of mud, sediment, etc. block the passage.
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