Mercury 9.8 Outboard (Whats the Flush Screw)

[briarleylodge]

I have a Mercury 9.8 Outboard which is running well but I have no manual when I brought it with the boat here in the UK.<br />I have a screw or bolt just under the main engine (outside) with FLUSH on it.<br />What is behind it and how do I refill it<br />Thanks in Advance.

 

[Yepblaze]

Re: Mercury 9.8 Outboard (Whats the Flush Screw)

You don't use that screw unless you decide you need to infuse the cooling system with water. It resides above the waterpump on many motors and to use it to flush with the motor running may could cause a problem with the impeller.<br /><br />There should be two other screws (one on the bottom of the bulb lookin geacase housing thing, and one just below the flat horizontal plate (anti cavitation) to vent.<br /><br />Pump oil into the lower screw hole till it runs out the vent screw hole.