Volvo Penta Thermostat 3587597

The Volvo Penta 3587597 Thermostat is a genuine OEM cooling system component engineered to provide precise thermal regulation in Volvo Penta gasoline marine engines.

This thermostat uses a wax-element valve mechanism that expands at a calibrated temperature to control coolant flow through the engine. By maintaining the correct operating temperature, it ensures proper combustion efficiency, optimal fuel burn, correct oil viscosity, and protection of internal engine components.

Operating at approximately 150F (65.5C), this thermostat is specifically designed for raw watercooled and closed cooling Volvo Penta systems. It helps prevent both overheating and overcoolingtwo conditions that can significantly reduce engine life and performance.

Manufactured to Volvo Penta’s strict OEM tolerances, this unit provides exact fitment, reliable opening characteristics, and long-term durability in harsh marine environments including saltwater exposure.

Key Features

• Genuine Volvo Penta OEM thermostat
• Precision-calibrated 150F (65.5C) opening temperature
• Maintains optimal engine operating temperature range
• Prevents overheating and cold-running conditions
• Ensures stable coolant flow under load
• Wax-element design for accurate thermal response
• Corrosion-resistant marine-grade brass and stainless construction
• Direct OEM replacement no modification required

Engine Compatibility

Volvo Penta Gasoline Engines (2001Present GM-Based Platforms)

Commonly used on:

• 3.0L GL / GS / GXi
• 4.3L V6 GL / GI / GXi / OSi
• 5.0L V8 GL / GI / GXi / OSi
• 5.7L V8 GL / GI / GXi / OSi
• 8.1L V8 Gi / GXi

Covers a wide range of late-model Volvo Penta sterndrive engines (2002+ applications).

Specific Engine Series Examples

• 4.3GXi-P / 4.3GL-P
• 5.7GiCE / 5.7GL-A
• V6-200 / V6-225
• V8-225 / V8-270 / V8-300 / V8-320

Used across V6 and V8 Volvo Penta gasoline platforms.

Drive & Application Compatibility

• SX sterndrives
• DP-S / DP-SM / DP-E / DP-G duoprop systems
• Inboard gasoline engines with similar cooling architecture

Serial Number Fitment Notice

Fitment depends on:

• Engine model and year
• Cooling system type (raw water vs closed loop)
• Thermostat housing design

Always confirm compatibility using your engine serial number before ordering.

Specifications

• Part Number: 3587597
• Type: Engine thermostat
• Temperature Rating: 150F (65.5C)
• Diameter: ~1-7/8″
• Operation: Wax-element, spring-loaded valve
• Construction: Brass thermal element, stainless steel spring and frame
• Cooling System Type: Raw water & closed cooling compatible (application dependent)

What’s Included

• Thermostat only
  (Seal / gasket sold separately unless specified)

When This Part Needs Replacement

Replace the thermostat if you experience:

• Engine overheating at idle or under load
• Engine running below normal temperature
• Slow warm-up or failure to reach operating temp
• Fluctuating or unstable temperature gauge
• Reduced fuel efficiency or poor combustion

Installation Notes

• Always inspect and replace O-ring/gasket separately
• Install with correct orientation (spring side toward engine)
• Clean thermostat housing and sealing surfaces
• Inspect cooling passages for debris or corrosion
• Verify proper temperature operation after installation

Alternate / Superseded Part Numbers

OEM Cross References

• Volvo Penta: 3587597
• Supersedes: 3862835

Aftermarket Cross References

• Sierra: 18-3615 / 18-3618
• OMC: 3701777
• Mercury: 27-53045 / 27-33179

Parts Desk Insight

This is one of the most common Volvo gas thermostats (post-2002)if your engine won’t hit temp or runs inconsistent, this is usually the first part to replace.

Shipping: Ships same or next day for fast Canada wide shipping.