Mercury MerCruiser Bell Housing Water Intake Hose Kit 8M0090859 | Bravo Sterndrives

Mercury MerCruiser Bell Housing Water Intake Hose Kit 8M0090859

• Part Number: 8M0090859 (Mercury reference: 32-8M0090859)
• Brand: Mercury Marine / MerCruiser
• Official Product Type: Bell Housing Water Intake Hose Kit
• Supersedes: 32-43437 (confirmed Mercury supersession)
• Replaced By: No further confirmed supersession — 8M0090859 is current
• System: Raw water cooling — gimbal housing / transom water intake
• Application: MerCruiser Bravo sterndrive bell housing cooling hose assembly

What This Kit Does

The Mercury Marine 8M0090859 is a genuine OEM bell housing water intake hose kit for MerCruiser Bravo sterndrive systems. It routes raw cooling water from the sterndrive through the transom assembly and gimbal housing into the engine cooling circuit. Over time the hose assembly becomes brittle, cracked, or restricted from heat cycling and age, reducing cooling flow and risking engine overheating. This kit replaces the complete hose assembly and all associated sealing and mounting components in one service.

This kit supersedes the earlier 32-43437. If your parts diagram or existing hardware shows 32-43437, 8M0090859 is the current service replacement.

Kit Contents

• Water hose assembly
• Rubber bushing
• Hose inlet insert
• Water inlet housing
• Water inlet housing gasket
• Mounting screws
• Installation tool

Compatible Applications

MerCruiser Bravo Sterndrives:

• Bravo One
• Bravo Two
• Bravo Three
• Blackhawk sterndrives

Common paired engine applications (Bravo transom assemblies):

• MerCruiser 4.3L V6
• MerCruiser 5.0L V8
• MerCruiser 5.7L V8
• MerCruiser 6.2L V8
• MerCruiser 7.4L V8
• MerCruiser 8.2L V8

Cooling hoses and transom components can vary by drive model, transom assembly design, and serial-number range. Always confirm using the drive and engine serial number before ordering.

Superseded Part Number

Confirmed Mercury supersession: 32-43437 → 8M0090859. If your parts diagram shows 32-43437, order 8M0090859 as the current replacement.

Service Interval

Inspect the bell housing hose assembly at every annual service. Replace proactively when the hose shows cracking, hardening, softening, or visible deterioration — or any time the gimbal housing or transom assembly is opened for major service. A failed hose can cause sudden loss of raw water flow and rapid engine overheating.

When to Replace This Kit

• Hose is visibly cracked, hardened, soft, or collapsing
• Evidence of water leakage at the transom assembly or gimbal housing
• Engine overheating traced to restricted cooling water flow from the transom
• Hose is brittle or has been compressed or kinked during previous service
• Annual service on a high-hour or aging Bravo sterndrive installation

Installation Notes

• Use the included installation tool for correct hose and bushing seating
• Replace the water inlet housing gasket — included in the kit — do not reuse the old gasket
• Inspect the gimbal housing water passage for corrosion or buildup before installing
• Confirm all mounting screws are tightened to Mercury service specification
• Run the engine and check for leaks at the hose connections and inlet housing before returning to service

Technical FAQ

Does 8M0090859 replace 32-43437?
Yes. 8M0090859 is the confirmed Mercury OEM supersession for 32-43437. Both numbers refer to the same bell housing water intake hose kit application on Bravo sterndrive assemblies.

Does this kit fit Alpha One sterndrives?
No. This kit is specific to MerCruiser Bravo and Blackhawk transom assemblies. Alpha One sterndrives use a different cooling hose arrangement. Confirm by drive model and serial number.

Should I replace this hose on a schedule or only when it fails?
Proactive replacement is strongly recommended at major service intervals or when the gimbal housing is opened. A hose failure underway causes immediate loss of raw water cooling flow, which can result in rapid engine overheating and serious damage.

What else should I replace at the same time?
When servicing the raw water cooling circuit on a Bravo sterndrive, consider replacing the raw water pump impeller at the same time. A worn impeller is a common cause of low cooling flow and overheating alongside an aging hose assembly.

Related Parts

• Jabsco 17954-0001-P MerCruiser Bravo Neoprene Impeller Kit
• Arco WP004 MerCruiser Replacement Water Pump
• Arco IP004 Mercury Replacement Impeller
• Arco WP001 Mercury Replacement Water Pump
• Sierra 18-3575 Marine Circulating Water Pump — MerCruiser / Volvo Penta / OMC

Parts Desk Insights

This is one of the most overlooked items in a Bravo sterndrive service. The bell housing hose is a rubber component that lives in a hot, pressurized environment and cycles between dry and wet conditions every time the boat is used. Most failures happen when the hose has been in service for many years without inspection — the exterior can look intact while the interior has hardened and restricted flow significantly. The most common ordering issue is customers not confirming the drive model: this kit is Bravo and Blackhawk only. If the drive is an Alpha One or a different sterndrive family, a different hose assembly will be required. When this job is open, replacing the raw water pump impeller at the same time is good practice — both components serve the same cooling circuit and the labour overlap makes it efficient.