Abstract: An exhaust stack engageable with engine exhausts, having an upper outlet section extending through a building wall, with means to prevent rain from descending in the stack; having also an intermediate section with a vertical pipe telescoped into the upper section and a horizontal extension thereon; and having further a lower, inlet section having a horizontal section telescoped into the horizontal extension of the intermediate section, the lower end of the inlet section having centering means so that it can be lowered over an engine exhaust pipe to center it and provide an annular space around the exhaust pipe. The intermediate and lower sections are supported for vertical adjustment by a hoist that is tracked around the upper section for angular adjustment. The lower section is horizontally adjusted into the intermediate section and transport means are provided for the adjustment. A temperature senser is provided near the inlet. The piping can all be rigid, heavy metal throughout.