No water from telltale

[Mark f]

I recently bought a boat with a 2005 f150 4 stroke. Water was not coming out of the telltale when I bought it and I figured the impeller needed replacing. Replaced everything for the impeller including the housing and all seals etc. Fired it up and no water. Before putting the lower unit back on, we detached the tubing from the telltale and blew through it to make sure it wasn't clogged. Easily blew air through to the bottom tube where the impeller housing slips onto the tube. Everything was put back in correctly and lined up when assembled. Any ideas?

Thanks,
Mark

 

[Takara]

Looking at the flow chart for the Yamaha 9.9 (most other Yamahas similar), the cooling water flows from the intake vents in the lower unit up to the engine. It takes two paths when in the engine. The initial path moves along the engine block/cylinder head to the very back plate. From there part of the cooling water goes to the pee hole so you can see that water is flowing. The other path moves up and over the cylinder head again to the thermostat. From there, the cooling water flows back down the lower unit to exit out the propeller hub.

If you do not see any water from the pee hole it is possible that the cylinder head flow vents are clogged.

A flow diagram can be found in the Selco Yamaha Outboards 1984-96 Repair Manual, all engines 2-250 HP, page 5-42.

Hope this gets you thinking about the flow and where to look for possible blockage(s).

Brian D
S/V Takara
KF6BL