Page 363 - REPOWER REFERENCE GUIDE (2020)

Measuring Exhaust Elbow Height
Riser Options—Sterndrive or Inboard

Model Low Medium High
3.0L (181 cid) N/A N/A N/A
4.3L (262 cid)
4.5L (275 cid) 76 mm (3 in.) 76 mm (3 in.)
5.0L (305 cid) and and 152 mm (6 in.)
5.7L (350 cid) 43 mm (1.7 in.) 119 mm (4.7 in.)
6.2L (377 cid)
8.1L (496 cid) 51 mm (2 in.) 152 mm (6 in.) 203 mm (8 in.)

Exhaust Angle Measurement
Measure the exhaust angle of each section of the exhaust system using an inclinometer as shown in the diagram below. Begin
the measurement at the exhaust elbow outlet continuing along each section to the exhaust exit point of the boat. All exhaust
angle measurements must be performed with the boat at rest in the water. Perform the first set of measurements without a load
in the boat. Perform the second set of measurements with the boat fully loaded. Refer to Loading Requirements.

Typical exhaust (except 8.1L [496 cid])
c a - Inclinometer
b - Exhaust hose or tube
a c - 305 mm (12 in.) minimum

b

18582

Typical exhaust 8.1L (496 cid)
a c c a - Inclinometer
b - Exhaust hose or tube
c - 457 mm (18 in.) minimum

b
8235
Boat Requirements

IMPORTANT: Consider the following requirements before performing the exhaust elbow waterline height measurement. No
prototype hulls or light layup hulls should be considered. Any measurement performed on nonproduction boats, prototype hulls,
or light layup hulls could be inaccurate and could result in product damage.
• All boats that display a CE certification capacity plate must use the maximum capacity as stated on the CE
certification capacity plate to perform the exhaust elbow waterline measurement.
• All boats that only display the U.S. Coast Guard (USCG) capacity plate must use the maximum capacity as stated on
the USCG capacity plate to perform the exhaust elbow waterline measurement.
• For boats that do not have a capacity plate, the maximum capacity load is the number of persons that can sit on
designated seating plus cargo excluding cabin space.
• Measurements used for official Mercury MerCruiser audit at the OEM boatbuilder must be performed on current production
boats. No prototype hulls or light layup hulls will be considered for official audit purposes.

90-8M0149179 eng NOVEMBER 2018 © 2019 Mercury Marine Page 10A-3