Mounting holes are not threaded. Use your existing bolts from your old engine, as the manufacturers use self-threading bolts, or a nut and bolt combination. Briggs 5 Torque Power Engine 140cc 7/8" x 3-5/32" keyed shaft. Compliance engine. Universal replacement engine for Snapper, MTD, Murray, AYP, Noma, and other rotary mowers. Model 9P602-0077.