Having been working on the project to rebuild the carbs of the engine. Debris has been found in the bowls of all four carbs. It seems like a good idea to do a carb rebuild before reinstalling the cabs back onto the engine.
Two of the three connections are already removed from the pump from the carb removal so only the input coming from the fuel filter need be removed. Two bolts secure the pump onto the engine which are removed, releasing the pump which is brought over to the bench.
Before disassembly, a test of the pump is conducted, given the tools that I have on hand to ensure that the internals are still functioning properly. My method is not standard but the results do demonstrate that the diaphragm , which is expensive is still working good. I did see black slime coming out of the pump during the tests though so a cleaning is in order.
Disassembly begins, the pump secured with four screws separating the two halves, the gasket and a seal are shown to be long since destroyed, the bottom portion is then disassembled, removing the plunger and spring followed by the valves. Now fully disassembled all parts are cleaned with carb cleaner and blown out with air except for the diagram which is carefully cleaned with a clean paper towel.
With all parts cleaned assembly was conducted stating with the lower plunger portion. Then the top portion starting with the valves, Gaskets are replaced on the top of the pump as it is assembled.
62Y-24452-00 -gasket
62Y-24471-00 membrane
The bolts holding the fuel pump together call for loctite 572. I use Loctite 592 as it is more readily available
Loctite 59214
Both side are brought together and tightened down progressively in a cross pattern. This is followed by basic testing again to ensure that everything inside was assembled properly. Back at the boat the pump is primed and tested manually before re-installation onto the motor. Finally reconnecting the hose from the fuel filter to the in port.
#yamahaoutboards #yamahaoutboards