Indmar Marine Circulation Water Pump – 383 / 350 | Part #551045
Keep your freshwater cooling circuit flowing with this genuine Indmar water circulation pump for the 383 and 350 cubic inch marine engines. Unlike the raw water pump which draws water from outside the boat, the circulation pump moves coolant through the closed freshwater cooling circuit — maintaining even engine temperature across all operating conditions.
Compatible with: Indmar 383 and 350 cubic inch marine engines fitted to Malibu, Moomba, Supra, and Tige boats. Contact us to verify fitment before ordering.
Circulation pump vs raw water pump — what's the difference?
These are two separate pumps performing two different jobs:
Raw Water Pump — draws water from the lake or river and circulates it through the heat exchanger to cool the freshwater circuit. Contains a rubber impeller requiring annual replacement.
Circulation Pump — moves engine coolant through the closed freshwater circuit — engine block, heat exchanger, thermostat housing, and heater circuit. Belt driven with an internal impeller — a long life component that requires replacement when worn or leaking.
Understanding the difference is important — symptoms of a failing circulation pump are often mistaken for a raw water pump or thermostat issue.
Signs your circulation pump needs replacing:
- Coolant leaking from the pump body or weep hole
- Engine overheating despite good raw water flow and impeller condition
- Rumbling or grinding noise from the pump bearing
- Coolant temperature uneven across the engine
- Visible corrosion or damage on the pump body
- Coolant loss with no obvious external leak source
Pro tip: When replacing your circulation pump always replace the thermostat and thermostat housing gasket at the same service — the cooling system is already partially drained making it the ideal time to service all related components together.
Pairs perfectly with:
- 986034 – Thermostat 160° Drilled LT1 & 5.7L F/W
- 985006 – Thermostat Housing Gasket
- 685001 – Raw Water Pump Full Barb
- 685007 – Raw Water Pump Impeller
Features:
- Genuine Indmar OEM water circulation pump
- Designed for Indmar 383 and 350 cubic inch marine engines
- Circulates freshwater coolant through closed cooling circuit
- Belt driven — no rubber impeller to service annually
- Built for continuous marine engine operation
- Direct replacement — no modifications needed
Part Number: 551045
In stock and shipped fast from Australia 🇦🇺
