I could really use your help. I recently purchased a used, gasoline powered 1994 motorhome. When I got it home I found that the Onan generator did not have an exhaust on it any longer. I have been unable to find where to extend the exhaust. Neither the manufacturer nor Onan seemed to be able to help me. I don't know if the exhaust should be run to the side of the motor home or directly down underneath the coach. I have not seen another coach like it to inspect it to find how is should be extended.
Clif, (North Zulch, TX)
Clif, (North Zulch, TX)
Clif, I am assuming the exhaust manifold and muffler are still intact and that you are simply missing the tail pipe extension, correct? Typically, the exhaust pipe is routed to the closest side or to the rear of the coach, whichever is the shortest run. It should not terminate directly underneath the coach. According to current RV codes and standards, it must extend beyond the sidewall by one-inch and not terminate directly below any window that has the capacity to open. Also, it must not terminate within six-inches of any item that opens into the interior of the RV such as a storage compartment or entry door. You’ll want to minimize the amount of turns the exhaust pipe makes. More elbows or turns in the piping increases the backpressure on the exhaust system. Be sure to support the exhaust pipe every two or three feet using appropriate tail pipe hangers of the correct diameter. 
