Regal 3300 Owner's Manual page 52

CHAPTER 1
Each Trip
SD
Make sure all exhaust clamps are in place and secure.

Look for exhaust leaking from the exhaust system

components, indicated by rust and or black streaking, water
leaks, or corroded or cracked fittings.
Inspect all rubber exhaust hoses for burned or cracked areas.

All rubber hoses should feel soft and be free of kinks.
Visually verify that water exits at the engine exhaust outlet.

Keep an ear tuned for any change in exhaust sound that

could indicate an exhaust component malfunction.
DO NOT OPERATE THE VESSEL IF ANY OF THE ABOVE
ITEMS EXIST; CONTACT A MARINE PROFESSIONAL!
At Least Annually (To be performed by a marine professional)
Replace exhaust hoses or mufflers if any evidence of

cracking, charring or deterioration is found.
Replace the engine water pump impeller along with the plate

and housing if necessary. This will help prevent cooling system
and in turn exhaust system overheating.
Inspect each of the metallic exhaust components for cracking,

rusting, leaking or looseness. Pay detailed attention to the
exhaust manifold, cylinder head and water injection elbows.
Make sure all exhaust clamps are in place and secure.
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