prop clearance???

jack duncan · Post by **jack duncan** » Sun Jul 23, 2006 08:28

I'm finishing up the fuselage restoration of my 65HP 7AC champ, I am having trouble fitting the engine cowling/nose bowl (not the original parts) "fiberglass nose bowl". does anyone know what the prop to nose bowl clearance should be? I think mine are to close togather, about 1/4" to 1/2" and what is the solution to this if there is one? I sure want to finish this thing so I can start building the wings. thanks, jack

MikeB · Post by **MikeB** » Sun Jul 23, 2006 11:42

Jack, I ran into the same problem on my 7AC, 65 with a fiberglass nose bowl. I wound up installing spacers between the engine mount and the rubber insulators, which moved the prop out to give me enough clearance. Even at that it only clears by about 1/4 inch or so. You can't change the demension of the length of the cowling, etc. I don't know if there's a difference between the metal or fiberglass nose bowl. Both of the other Champs on our field have flange crankshafts, mine is a tapered shaft. I've heard there is a difference between those two, but not sure.
I also think the new "rubber engine mounts" (which are softer) compress more than the old hard rubber mounts.

Kind of an 'unsolved' mystery

, but spacers work. Of course, you also need longer bolts.

Mike

Ron Babos · Post by **Ron Babos** » Sun Jul 23, 2006 16:58

Jack: If you have 1/8 inch it will work fine. I originally had 1/16 on mine, and it was ok but installed washers when I changed the rubber bushings.
On that note, the old stock rubbers that I put on last year do not have any cracks in them, and engine has not sagged. Sorry I brought that up again, Mike.

Ron