fuel pump for Mercury 90 2 stroke?

[Kurt Watson 72]

Hi, I have a 1983 Mercury 90 6 cylinder 2 stroke outboard. I think the fuel pump diaphragm is bad. Would anyone know where I can get a replacement pump, or a rebuild kit? Number on the pump is 66529

Engine was running perfect, and then all of the sudden started bogging really bad under throttle, but still idles OK. I thought I was running out of fuel, but I still had a 1/2 tank, A friend said it's likely the diaphragm.

 

[roscoe]

Any Mercury dealer should have a rebuild kit, or get you a new pump.
Or online from a Merc dealer. Maybe here on iboats, but I couldn't find it.

Oem Mercury parts:

Diaphragm Assembly 89031A3 $17.
CHECK VALVE KIT 21-8M0084277 $40
Entire new fuel pump, $89 13527A1

Aftermarket parts are available a little cheaper.

 

[1960 Starflite]

Vent IS open on fuel tank, Right ?

 

[v191Checkmate1969]

Hi, I have a 1983 Mercury 90 6 cylinder 2 stroke outboard. I think the fuel pump diaphragm is bad. Would anyone know where I can get a replacement pump, or a rebuild kit? Number on the pump is 66529

Engine was running perfect, and then all of the sudden started bogging really bad under throttle, but still idles OK. I thought I was running out of fuel, but I still had a 1/2 tank, A friend said it's likely the diaphragm.

The fuel pump is a good place to start. I would also check (or just replace if they are old) all the fuel lines with modern tubing. My 1978 Black Max was bogging terribly and fuel lines were probably older than me (and I ain't young!). The inner lining of the older lines can break down and cause debris to flow toward the fuel filter and pump and clog it. At least that is what was going on with mine.

 

[flyingscott]

I would start with a compression. And spark test