VOLVO OMC 4.3 V6 ELBOW MANIFOLDS KIT

Function and technical context

Exhaust manifolds and low elbows are part of the gas evacuation and seawater cooling circuit in stationary marine engines. The manifolds collect the combustion gases from the cylinders and channel them to the outside of the boat, while the return elbows direct the cooling water from the heat exchanger to the exhaust pipe, where it cools the gases before being expelled. The reduced height of these collectors – low type – allows them to be installed in engine compartments with little clearance above the block, a common configuration in the 4.3 liter GM 262 CID V6 engines assembled by Volvo Penta and OMC. If the system fails due to corrosion, cracks or leaks in the gaskets, the hot gases can overheat the block, damage the head gasket or cause water to enter the engine, with serious and irreparable consequences for the engine. This kit includes two cast iron manifolds (ref. Volvo 3847499 / 3852338 / 3857656), two return elbows (ref. OMC 3857944 / Volvo 3863061) and the complete set of gaskets and mounting screws, allowing a complete replacement of the assembly without the need to purchase separate components.

When to replace this part?

The most common symptoms of deterioration in manifolds and lower elbows are the appearance of rust stains or white efflorescence at the joints, loss of coolant, metallic noise or exhaust with a burnt smell in the engine compartment and progressive overheating of the propeller during navigation. Galvanic corrosion and continuous thermal cycles degrade both the cast iron and the seals, so it is recommended to visually inspect the assembly during each seasonal maintenance and replace it preventively if there is any sign of porosity, cracks or leaks, especially in engines with more than five years of service or that operate in salt water. Changing the complete kit – manifolds, elbows and gaskets – at the same interval prevents a second opening of the engine and guarantees the tightness of the system, reducing the risk of serious breakdowns at sea.

Compatible Volvo Engines

Equivalent manufacturer part numbers