Blue Bird bus both sides broken manifold studs removal

[xbus]

Blue Bird propane bus, manufacture date June, 2019
Manifold studs broken on both sides

1. Jack the front frame of bus
   

   

2. Remove front wheels

3. Remove front fender(both sides).
   Usually the top 2 nuts mounting the fender rust out, need to cut out
   The bottom 4 nuts always rust out too, can use a vise grip to grasp the back side. All the nuts are 13mm.
   

   
   
   
   
   
   
   

4. Remove exhaust Y pipe
   Disconnect the top two oxygen sensors, one each side.
   Heat the front four nuts connected to the manifold, two of each side, and two of back side. Remove them. Usually 15mm nuts on the front , sometimes 14mm.
   

   

5. Remove both sides manifold
   13mm nut hold stud, 10 on each side, 5 on top, 5 on bottom. Totally 20 studs and nuts on both sides. Usually, studs will come out together when you remove the nuts.
   Remain one stud with nut on the top, just break it loose. It will hold the manifold.
   The middle one on bottom is a little bit difficult to remove for the space is very limit. It is just above the frame. Some techs remove the aluminum shield underneath for more space.
   Trick: Use a 3/8-inch rachet + 3-inch extender + 13mm socket break loose
   

   
   
   Then use a 3/8-inch electric rachet + 3-inch extender + 13mm socket remove the stud.
   
   
   
   
   
   
   This case broken 5 studs. 2 on left side, 3 on right side.
   
   

6. Welding out the broken studs
   

   
   
   
   

7. Install new studs on both sides. Put antiseize on the threads.

8. Install new gaskets on both sides

9. Clean the surface of the manifold

10. Reinstall manifold on both sides

11. Reinstall Y pipe

12. Running the bus to test if there is any leak

13. Reinstall front fender on both sides