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FLASHSALE26

Exhaust Riser Screw for MerCruiser 4.3L, 5.0L, 5.7L and 6.2L Engines — Replaces 865982077

Regular price $20.99

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Product Details

This Exhaust Riser Screw is a replacement fastener for specified MerCruiser exhaust manifold and riser assemblies. It is listed for 4.3L, 5.0L, 5.7L and 6.2L MerCruiser applications, including selected Alpha and Bravo sterndrive and inboard configurations.

Use the OEM reference and the engine-model information below to compare this screw with the fastener removed from your engine. Fitment can vary by engine model, drive type, production year and serial-number range.

  • Thread specification: .375-16
  • Length: 10.500 inches
  • Application: exhaust riser mounting
  • Product type: individual replacement screw
  • For selected MerCruiser Alpha, Bravo and inboard applications

Part Number Matrix

Use the following manufacturer reference when comparing the replacement screw with your existing part or service-manual information.

Brand Part Number Reference Type
MerCruiser 865982077 OEM reference

Engine & Model Compatibility

The following MerCruiser engine applications are associated with this exhaust riser screw. Confirm the complete model designation, drive type, year and serial-number range before ordering.

Brand Model Application Notes
MerCruiser 350 MAG MPI HORIZON ALPHA/BRAVO Selected Alpha/Bravo applications
MerCruiser 357 Alpha 4V Alpha application
MerCruiser 357 MAG Bravo 4V Bravo application
MerCruiser 377 MAG MPI BRAVO Bravo application
MerCruiser 383 MAG Inboard 4V Inboard application
MerCruiser 383 MAG STROKER Confirm complete model and serial range
MerCruiser 383 MAG STROKER BRAVO Bravo application
MerCruiser 383 MAG STROKER INBOARD Inboard application
MerCruiser 383 MAG BRAVO 4V Bravo application
MerCruiser 385 Performance Tuned Confirm complete model and serial range
MerCruiser 4.3L MPI ALPHA/BRAVO Alpha/Bravo application
MerCruiser 4.3L CARB ALPHA/BRAVO Alpha/Bravo application
MerCruiser 5.0L MPI ALPHA/BRAVO Alpha/Bravo application
MerCruiser 5.0L CARB ALPHA/BRAVO Alpha/Bravo application
MerCruiser 5.7L CARB ALPHA/BRAVO Alpha/Bravo application
MerCruiser 5.7L MPI HORIZON MIE Inboard application
MerCruiser 5.7L MPI MIE Inboard application
MerCruiser 6.2L MPI HORIZON MIE Inboard application
MerCruiser 6.2L MPI MIE Inboard application
MerCruiser MX 6.2L MPI HORIZON MIE Inboard application
MerCruiser MX 6.2L MPI MIE Inboard application
MerCruiser MX 6.2L MPI BRAVO Bravo application
MerCruiser MX 6.2L MPI HORIZON BRAVO Bravo application

Technical Specifications

Part Type
Exhaust riser screw
Thread Size
.375-16
Length
10.500 inches
Application
Exhaust manifold and riser mounting
Drive or Installation Type
Selected Alpha and Bravo sterndrive and inboard applications
OEM Reference
865982077

What's in the Box

  • 1 × Exhaust Riser Screw

Installation Notes

  1. Disconnect the battery and allow the engine and exhaust components to cool completely before beginning work.
  2. Remove the existing fastener and compare its thread, length and head style with the replacement screw.
  3. Inspect the threaded hole and surrounding exhaust-riser hardware for corrosion, damaged threads or other signs of wear.
  4. Clean the threads as required by the engine manufacturer's service procedure.
  5. Start the replacement screw by hand to prevent cross-threading.
  6. Tighten the fastener using the torque value specified for your exact MerCruiser engine and exhaust assembly.
  7. After installation, verify that the riser is seated correctly and inspect for exhaust leakage before returning the engine to normal service.

Troubleshooting & FAQ

How do I confirm that this screw fits my MerCruiser engine?

Compare the OEM reference 865982077, thread size, length and original fastener with the information in your MerCruiser service documentation. Also confirm the complete engine model, drive or inboard configuration, production year and serial-number range.

Is this a complete exhaust riser hardware kit?

No. This listing is for one individual exhaust riser screw. Gaskets, washers, additional fasteners and other exhaust components are not included unless separately stated.

Can I reuse the old exhaust riser screw?

Do not reuse a fastener that is corroded, stretched, damaged or unable to achieve the specified torque. Replace questionable hardware and inspect the mating exhaust components before assembly.

What torque specification should I use?

Use the torque specification in the service manual for your exact MerCruiser engine and exhaust assembly. Do not substitute a general torque value, because exhaust fastener requirements can vary by application.

Will this screw work on both carbureted and fuel-injected engines?

The listed application data includes both carbureted and MPI MerCruiser models. Confirm the exact model, drive or inboard configuration, year and serial-number range rather than relying on the fuel-delivery system alone.

Should I use anti-seize compound?

Follow the lubricant and thread-preparation instructions in the service manual for your engine. If a compound is permitted, apply it sparingly and account for its effect on the specified torque.

What symptoms can indicate a damaged exhaust riser fastener?

Visible corrosion, damaged threads, a stripped head, loose riser hardware, movement at the riser joint or signs of an exhaust leak may indicate that the fastener or related components require inspection.

Safety & Important Information

  • Verify the part number, dimensions and application details against your original fastener and the service documentation for your exact engine.
  • Engine-model listings do not replace confirmation of year, serial-number range and complete configuration.
  • Use appropriate marine service procedures and a calibrated torque wrench during installation.
  • Professional installation is recommended if the exhaust assembly, threaded block or riser shows corrosion or damage.

About Sea Sierra

  • Marine replacement parts selected for common service and repair applications.
  • Product information is organized to help you compare part numbers, dimensions and engine applications before ordering.
  • For the best fitment result, keep the complete engine model, drive or inboard configuration, year and serial number available when checking replacement parts.

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