MerCruiser 330/340 Inboard Lower Thermostat Housing 

Lower thermostat housing.

Replaces MerCruiser 90736A18 and Osco MC552-BB.

Fits MerCruiser V8 Models 330, 340 and 454 Magnum, inboard and stern drive units (center riser direct replacement).

Compatible parts:

• MC-1-89011 direct replacement water cooled exhaust manifold.
• MC-20-44354 direct replacement water cooled center discharge riser. Accepts 4" I.D. exhaust hose (8 degree angle).
• MC-20-98502 direct replacement water cooled center discharge riser. Accepts 3" I.D. exhaust hose (0 degree angle).
• MC-20-98504 direct replacement water cooled center discharge riser. Accepts 3" I.D. exhaust hose (15 degree angle).
• MC-20-93320A3 manifold to riser 3" spacer blocks (pair) with fastener and gasket package.
• MC-20-93322A3 manifold to riser 6" spacer blocks (pair) with fastener and gasket package.

Manufactured by Barr Marine. Part number MC-29-90736.