If you are going to have to hire a crane anyway here is a suggestion that
eliminates any stress on the floors and makes removal and resetting a simple
single operation that minimizes crane time.

Have a "U" shape frame welded up of 3" square heavy wall steel tubing.
The legs of the U should be the distance from the edge of the cabin top to
the lift point of the engine plus a couple of inches and the bottom of the U
should be the length needed to clear any obstacles plus a few inches.
Reinforce the corners by welding on some gusset plates. Bolt lifting rings
to the ends of the legs. A 20' stick of 3" heavy tube will set you back
about $80 and welding another $50 or so.

When the crane arrives, have it lift the frame using one ring and maneuver
the lower leg into the boat. The upper leg will be over the cabin top. Hook
the engine to the bottom leg and lift. The weight of the engine will
balance the frame horizontally. When it gets high enough to clear any
obstacles have the crane swing back out of the cabin and lift out all in one
operation. Save the frame for use in resetting the engines.

I set my 550 lb Yanmar under the cockpit single handed using a frame welded
up from 2" tube, a rolling gantry cobbled together from a pair of old barn
door tracks bolted to a 2x8 and a chain fall.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Paul Wiggins" wrote in message
...
I need to build a contraption to remove two large, old, heavy engines.
(1968 CC 427's).

The boat is on stands and there's no way I know of to get a boom up, over
and inside the wheelhouse.

So... I'm considering building tripods on either side of the wheelhouse...
running a metal I beam thru the windows over the engines... lifting...
placing them a wooden bed... sliding the engine back to the rear... where
a small crane can lift out.

The question I have is.. what to build the tripods out of... 4x4's our of
sistered 2x4's? Something beefier...

I recall reading somewhere they weight in at 1700lbs.

many thanks.