National Aeronca Association Bulletin Board

Hello All,

I've been been looking for the torque to use on the 7/16 bolts used to mount the actual engine to the engine mount thru the rubber bushing and can't find anything. The TCM service bulletin has 7/16 bolts being torqued 400-450 inch pounds or 33-37 foot lbs.

Is this right?

Joel,
My Continental manual has 60-80 in.lbs. for conical mounts and 180-190 in.lbs. for the Lord mounts.
Paul

Paul is correct on the 60-80 for the conical mounts. Having said that don't be surprised if the mounts show cracks around the edges after a year or less. Look like #%## but doesn't seem to hurt anything and doesn't seem to have anything to do with torque. I've replaced them in a Champ after 3-5 years and within a year or so they look the same again. I've pulled old conical mounts that had been in 20 years that were worn from vibration but not cracked. I suspect it has something to do with the make up or production process and tried several years ago to pin Wag Aero down for one as to what has changed but of course it's a vendor product for them. I've tried others like ACS with basically the same result and I suspect they get the mounts from the same vendors. So unless something else comes along we live with the surface cracks.
Mike Berg