HFP-702 is a premium OEM replacement electric fuel pump engineered specifically for MerCruiser marine inboard, sterndrive, and tournament towboat engines. This heavy-duty unit serves as a direct performance interchange for Sierra 18-35433, 18-8867, and Mercruiser factory part number 8M0125852. Marine environments put immense stress on fuel systems; water separation, stagnant fuel, and continuous high-load operations frequently cause factory pumps to corrode or experience internal breakdown. A failing pump struggles to feed the demand of electronic fuel injection (EFI, TBI, or MPI) systems, triggering hard starting under warm conditions, top-end power drops, engine surging, or a complete lack of fuel rail pressure. HFP-702 completely restores dependable engine operation by maintaining factory-specified high-pressure delivery across all displacement platforms—from the workhorse 4.3L V6 up to the high-performance 5.7L Black Scorpion, 6.2L MX, and big-block 7.4L/8.2L MPI engines. Built to comply with strict safety standards, the internal pumping mechanisms feature industrial-grade FKM compound seals that fully combat the harsh corrosive actions of modern ethanol blends and salt air, preventing fuel bypass leakage and extending your engine's reliability out on open water.
Features & Benefits:
Marine-Grade Protection: Specially coated external body and explosion-proof terminal design engineered to withstand harsh moisture, salt, and marine environments.
Stable High-Pressure Output: Delivers unyielding fuel rail pressure to feed multi-port injection (MPI) and throttle body injection (TBI) systems under sustained heavy throttle loads.
Industrial-Grade FKM Seals: Constructed with premium, high-quality FKM fuel-safe elastomers to resist swelling, drying, and tearing caused by modern E10 marine fuels.
Direct Fit Architecture: Dimensionally identical to original factory assemblies for an easier swap into the original fuel cool or vapor separator module.
Advanced Turbine Internals: Features a balanced turbine design that minimizes operating noise and structural vibration while delivering superior mechanical efficiency.
Optimized Cooling Path: Designed to let fuel circulate continuously around the internal motor core, reducing operating temperatures and preventing vapor-lock issues during long idles.
Ethanol Shield: Built with corrosion-proof internal components that prevent gumming and seasonal fuel varnish build-up during winter storage.
THE IDEAL REPLACEMENT FOR MERCRUISER & SIERRA PART NUMBERS: 8M0125852, 18-35433, 18-8867, 935433
Package Includes: High-Pressure Marine Fuel Pump
WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
- Fuel Type:
- Gasoline
- Aftermarket Type:
- OE Replacement
- Vehicle Type:
- Outboard
- Brand Name:
- Quantum
Serviceable & Wear Items: Please note that fuel filters, strainers, and rubber components (seals/grommets) are considered maintenance items. While these are protected against manufacturing defects, the lifetime warranty does not cover replacement for items that have reached the end of their functional service life due to normal debris accumulation or natural material aging (such as cracking or swelling from long-term fuel exposure).
This warranty applies only to the original purchaser and is non-transferable. Improper use or installation voids the warranty. Quantum is not responsible for incidental costs resulting from product failure. Contact customer service to troubleshoot, diagnose issues, and file a warranty claim.