Indmar Marine Impeller Pump Gasket – Johnson | Part #685008
Never reuse an old gasket — this genuine Indmar Johnson pump gasket is the correct OEM replacement seal for the Johnson raw water pump fitted to Indmar marine engines. A small but critical component that ensures a leak-free seal on your raw water pump — protecting your cooling system integrity and keeping your engine at safe operating temperature all season long.
Compatible with: Indmar marine engines fitted with Johnson raw water pumps on Malibu, Moomba, Supra, and Tige boats. Contact us to verify fitment for your specific model year before ordering.
What does the pump gasket do?
The impeller pump gasket seals the pump housing cover to the pump body — preventing raw water from bypassing the impeller or leaking externally. A failed or reused gasket can cause:
- Raw water leaking from the pump housing
- Loss of pump suction pressure — reducing cooling water flow
- Air ingestion into the cooling circuit — causing overheating
- Accelerated corrosion at the pump housing sealing face
- Contamination of the bilge with raw water
Why Johnson?
Johnson Pump is one of the most respected names in marine water pumps — supplying OEM raw water pumps to major marine engine manufacturers including Indmar. The Johnson pump gasket is engineered specifically for Johnson pump housings and dimensions — ensuring a precise, leak-free fit that generic gaskets simply cannot guarantee.
When should you replace it?
Replace this gasket every time you:
- Remove the pump cover to replace the impeller
- Replace the raw water pump body
- Notice any weeping or leaking around the pump housing
- Carry out your annual impeller service
Pro tip: This gasket should be replaced at every impeller service — part #685007. It costs almost nothing compared to the impeller itself and takes seconds to fit. Reusing the old gasket to save a few dollars risks a weeping pump housing that slowly allows air into your cooling circuit — reducing cooling efficiency and potentially causing overheating even with a brand new impeller fitted. Always replace them together.
The complete impeller service kit:
For a complete Johnson pump service order these three parts together:
- 685007 – Raw Water Pump Impeller
- 685008 – Impeller Pump Gasket Johnson (this part)
- 685001 – Raw Water Pump Full Barb (if pump body replacement required)
Pairs perfectly with:
- 685007 – Raw Water Pump Impeller
- 685001 – Raw Water Pump Full Barb
- 845040 – Hose J-Formed with Spring
- 841033 – Hose Formed 1" 90°
- 866081 – Thermostat Housing Aluminium Full F/W
- 986034 – Thermostat 160° Drilled LT1 & 5.7L F/W
Features:
- Genuine Indmar OEM part
- Engineered specifically for Johnson raw water pump housings
- Precision cut for perfect pump housing sealing surface fit
- Prevents raw water bypass and external leaking
- Single use — always replace, never reuse
- Replace at every impeller service
- Direct replacement — no modifications needed
Part Number: 685008
In stock and shipped fast from Australia 🇦🇺
