Small Engines (Lawn Mowers, etc.): Changing blade on Scotts turfmaster mower, scotts turfmaster, inch bolt

Question
Hello! We are trying to change the blades on our scotts turfmaster lawn mower - Model #C4013050 Serial # S005442320249

One of the bolts had fallen out & we matched the replacement at the hardware store to the remaining bolt.  However, it doesn't work!  It only engages about 3-4 threads and doesn't tighten.  It's a 3/8 X 1 inch bolt.  Do we have to buy special bolt to put these blades on?  Also, does the blade sit inside the tabs or does it rest on the tabs.

Thank you.

Answer
Hello Joyce:

These Bolts can Be Purchased Locally. However, they MUST BE GRADE 8 BOLTS. **A GRADE 5 BOLT WILL SHEAR AND THE BLADE WILL FLY OUT FROM UNDER THE MOWER** The Blade is Held Stationary by the Tabs. The Length Bolt you Described is a Little Short. Usually the Bolt Length is 1 1/4" or 1 1/2". This May be Why the Blade Bolt Loosened and Fell Off. I Suggest you Replace Both Bolts with 1 1/4" Bolts. Hope this helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

Good Luck

Respectfully

John