Page 172 - REPOWER REFERENCE GUIDE (2020)

Manifolds, Elbows, and Risers for Wet Joint
Lubricants, Sealants, Adhesives

Tube Ref No. Description Where Used Part No.
Loctite 567 PST Pipe
9 Sealant Exhaust manifold and elbow plugs 92-809822

19 Perfect Seal Gasket surface exhaust manifold to elbow and to riser 92-34227Q02
Models Covered

Models Covered Serial Number Or Year
Wet Joint Models
Sterndrive models 0M300000–0M599999
Inboard and TowSport models 0M310000–0M316999
General Information

Seawater Cooled Models
The term seawater cooled, also known as raw water cooled or RWC, refers to the use of water, such as seawater, for cooling
throughout the system, in the engine cooling passages, and in the exhaust water jackets. This water source is picked up
through the sterndrive and engine seawater pump.
Cold Manifolds

Cold manifolds contain fluid that enters the exhaust manifold near seawater temperature.
Wet Joint
Wet joint is a description based on the style of exhaust system on these engines. The wet joint exhaust system confines both
the engine seawater and exhaust gases with the same gasket sealing surface at the exhaust manifold to elbow joint (wet joint).
In the exhaust elbow, the engine seawater and exhaust gases mix and discharge together. This system was used on engines
produced prior to 2002. These engines are equipped with cold manifolds.
Closed Cooled Models

1/2 Loop
Engine models in service manuals number 24, 25, and 32 are 1/2 closed cooling systems or 1/2 systems. The term 1/2 closed
cooling system refers to the use of ethylene glycol mixture in the engine cooling passages and the use of seawater in the
exhaust water jackets.
Full‑Loop
Some wet joint engine models covered in this section may have a full‑loop kit installed. The term full closed cooling system,
also known as full fresh water cooled or full FWC, refers to the use of ethylene glycol mixture in the engine and the exhaust
water jackets.

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