P/N 51220 Exhaust manifold assembly / 99746A17 x 2
P/N 51110 / 98504A3 or 51140 / 807988A2 Elbow (3 inch or 4 inch) x 2
P/N 32170 Gasket / 27-99757 x 2 P/N 30240 Gasket / 27-863724 x 2
P/N 13991 90 degree hose fitting / 22-806926 x 2
P/N 13992 Drain plug / 22-806608A02 x 2
P/N 80140 O-ring for plug / 25-45253 x 2
P/N 22391 Stud / 16-49545 x 8
P/N 21248 Flange nut / 11-46335 x 8
P/N 89120 Upper bellow / 32-44348T x 2
P/N 89130 Lower bellow / 32-14358001 x 2
P/N 01100 Hose clamp / 54-815504372 x 12
P/N 50750 Exhaust tube / 14478T01 x 2
Before removing the assembly, make sure to disconnect the battery from the terminals. It is important to note that after installing the two piece assembly, the height of the elbow will be lower by up to a half inch. Refer to your Mercruiser repair manual to determine the ‘minimum’ riser height. If, it is not at or above the minimum height, a GLM spacer can be installed to raise it up to meet OEM spec.
1. Start by removing all the parts and mounting hardware (keep these).
2. Disconnect the water hose which is connected underneath, and remove whole assembly.
Before beginning, wipe down all mounting and connecting surfaces of all pieces to ensure they are clean and free of oil or grease.
1. Start by installing the new water hose fittings into the new assembly, with the openings facing towards the front of the boat, pointed slightly outwards by a few degrees. Install the gasket, and torque the mounting screws to 33 ft.lbs or 45 Nm.
2. Next, install the starboard (right side) water hose with the clamp firmly tightened. You’ll need to route the port (left side) water hose underneath the power steering pump onto the fitting for the hose, and secure the clamp tightly.
3. Check the condition of the water shutters (flaps) – if they are damaged and do not function properly, replace these with GLM P/N 89175. If they are fine, install the plugs into the new elbows.
4. Make sure to apply a sealant or thread locker onto the main bolts connecting the manifold to riser, and torque these to 33 ft.lbs or 45 Nm. (note, these torque specs are different than the aluminum assemblies)
5. Connect the upper bellow, followed by the curved elbow tube and then the lower bellow using the included clamps.
P/N 01100 Hose clamp
P/N 22391 Steel stud, threaded on both ends (used for P/N 51110)