REFLECTOR:IO-540 Engine Mount Type

[Jack Sheehan]

I would guess that while building my aircraft at the service center 
over a period of 3 years there were at least a half dozen IO-540 260 
hp engines that were installed by various builders and I never knew 
of anyone that had an engine mount problem with the factory mount. It 
is a tight fit because of the angle of the bracket but the mount is 
flexible enough that you can pull it into place.
Take two strong backs. I hope you are not trying to mount the engine 
mount to the aircraft first. The real difficulty in doing the engine 
mount is to make sure the engine is centered in the cowl opening so 
you have a match between the cowl and the propeller hub. One would 
think that if you centered the engine on the firewall the rear would 
match the cowl opening. It might if you are lucky. The engine really 
does not care where it is on the firewall so center in the opening. 
After doing it I think the best method is to have a plumb bob 
centered vertically and mark the point for a horizontal center a 
laser survey sight would also work if you have access to one. Or like 
in my case try and center it and then go back and spend a week 
working on modifying the cowl to fit. You will also find that the 
plennum may have to be cut down because when you get the engine 
centered in the opening  the plenum hits the top cowl
Jack
N55XL