Exhaust heat riser issue
Thread Starter
Instructor
Joined: May 2013
Posts: 199
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From: Fair Grove Missouri
Exhaust heat riser issue
The motor (427/390 hp) is back in the 1969. The problem was after attaching the right exhaust header pipe the heat riser would not rotate, it appeared to be hitting something and not fully opening. On and off several times. The problem was interference with the construction of the header pipe that holds the doughnut. It appears the inside diameter of the pipe was insufficient and interfered with the free movement of the stainless steel butterfly. Ground part of the butterfly and had full movement. We did not have problems with overheating prior to rebuild. Just a heads up for a potential cause of excessive motor heat.
