Cub Cadet MTD 90 Series - Manual (Page 101)

Exhaust
95
6. Remove the two muffler nuts using a 13mm wrench
and lift the muffler off of the engine. See Figure 8.10.
7. Clean all of the gasket material off of the cylinder
head and the muffler (if reusing the muffler)
NOTE: The MTD engine uses a graphite exhaust gasket.
It is not reusable and must be replaced every time
the muffler nuts are loosened.
8. Install a new gasket.
9. Install the muffler and tighten the muffler nuts to a
torque of 13 - 16 ft-lbs (18-22 Nm).
10. Test run the engine before returning to service.
Figure 8.10
Muffler nuts