2006 Yamaha F50 cooling system Leaking?

Len Dog

Cadet
Joined
May 20, 2007
Messages
27
-My lower unit was damaged,.
-I purchased a new lower unit housing & re assembled it.
-I have no speedometer so I discarded the excess rubber tubing at the front of the lower unit and installed the plug that was at the end of the tube.
-I reinstalled the lower unit.
-I hooked up a garden hose and test run it and it pumped water fine.
-when running the engine in the lake pressurized water flows from the front of the upper casing where there is a small hole as well when the engine is reved up water spews from the shifter shaft grommet on the bottom of the upper coweling. It also does pump water from the outlet where it is supposed to.
-I removed the lower unit, disassembled the water pump,checked assembly with the shop manual, installed a new impeller, siliconed down the water pump gasket, and re Instaled the lower unit. No change.
-I installed the lower unit on another engine the same, test run it in the water and there is no change it acts the same on this engine.
??????

Thanks:)
 
Top