I recently posted reguarding the surge problem on my lawn boy dura force. I found the bits needed at a local hobby store costing only $3 and was able to enlarge the holes with a old hand drill with the crank and right angle gears. In fact the drill was so old it even said made in the usa instead of made in china. The engine now runs great, however the welds holding the muffler to the inlet pipe broke as well as welds holding the muffler to the sheet metal guard. I only see one screw holding the muffler to the block horizontaly plus the 2 holding the inlet pipe to the engine mounting plate. Was this a design flaw in the mower or did a screw back out? The dealer wants $80+ for the new assembly which i feel is totally stupid. does anyone out here have a extra muffler assembly laying around for the duraforce engine as i belive the assembly was the same for the whole duraforce line or have leads on getting one for less then $80?