When I purchased this boat, the previous owner had removed the
saildrive engine and engine mount. I am re-installing this engine back
into the boat. This is an old OMC Zephyr Saildrive. The reason the
engine mount was removed was because the bond between the engine mount
and the hull is terrible. The engine mount popped right out! No bond
at all and lots of voids in the epoxy. Three of the mounting lug nuts
fell out. This must have leaked terrible!

The installation instruction manual says, "An alternate method of
supporting the engine mount is to use reinforced epoxy putty to fill
the space between the hull and the bottom of the engine mount flange,
in a conical shape, including complete enclosure of the lug nuts."
"Reinforced putty is made by adding fiberglass dust to the putty to
form a strong bonding material."

My questions are,
What are they referring to as Fiberglass dust? Are they referring to
West system 403 Microfibers?
Adding fiberglass dust to the putty... are they saying that the epoxy
has already been thickened? If so, what would you use, Colloidal
Silica and microballons, or would you use 404 to thicken up the epoxy?
I just want to be sure to use the right stuff.
Thank you,
Dan