Thermostat Kit 160° – Fits Volvo Penta & OMC V6/V8 (Replaces 383307, 3856961, 3587597)

$22.49

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Thermostat Kit 160° – Fits Volvo Penta & OMC V6/V8 (Replaces 383307, 3856961, 3587597) is backordered and will ship as soon as it is back in stock.

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Product Details

This Thermostat Kit 160° – Fits Volvo Penta & OMC 4.3L, 5.0L, 5.7L V6/V8 Engines is a direct replacement for various gasoline engines. It is designed for Volvo Penta 3.0L, 4.3L, 5.0L, 5.7L, and 5.8L V6/V8 models from 1993 to 2003, as well as OMC Cobra 4.3L, 5.0L, 5.7L, and 5.8L engines manufactured between 1991 and 1997.

It serves as a direct interchange for Volvo Penta part numbers 3587597, 3852111, 3852071, and 383307; Sierra 18-3677 and 18-3653; and GLM 13430 and 13060.

Engineered for direct OEM-level installation.
Maintains a 160°F (71°C) operating temperature in raw water cooled engines.
Kit includes thermostat, gasket, and O-ring for a complete service.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket brands.

Brand	Part Number
Volvo Penta	3587597
Volvo Penta	3852111
Volvo Penta	3852071
Volvo Penta	383307
Sierra	18-3677
Sierra	18-3653
GLM	13430
GLM	13060

Engine & Model Compatibility

Confirm your engine model and year in the tables below.

Volvo Penta Applications: This thermostat fits V6 and V8 engines from 1993–2003. It does not fit 4-cylinder models.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Volvo Penta	3.0L	All	4-Stroke	1993+	3856961	All models except 4-cylinder engines
Volvo Penta	4.3GL	All	4-Stroke	1993–2000	383307	All 4.3L models
Volvo Penta	4.3A, 4.3B	All	4-Stroke	2001–2002	383307
Volvo Penta	4.3GS, 4.3Gi	All	4-Stroke	1993–2000	383307
Volvo Penta	5.0FL, 5.0FLP	All	4-Stroke	1993–1996	383307
Volvo Penta	5.0GiP, 5.0GLP	All	4-Stroke	1997–2000	383307
Volvo Penta	5.0GL, 5.0GXi, 5.0OSi	All	4-Stroke	2001–2003	383307	A, B models
Volvo Penta	5.7L	All	4-Stroke	1993–2000	383307	All 5.7L models
Volvo Penta	5.7L	All	4-Stroke	2001–2003	383307	All except OSi
Volvo Penta	5.8L	All	4-Stroke	1993–1996	383307	All 5.8L models

OMC Cobra Applications: Fits V6 and V8 engines from 1994–1997. Excludes 4-cylinder applications.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
OMC	4.3L	All	4-Stroke	1994–1997	383307	Except 4-cylinder engines
OMC	4.3HO	All	4-Stroke	1994–1997	383307	High Output version
OMC	5.0L	All	4-Stroke	1994–1997	383307
OMC	5.7L	All	4-Stroke	1994–1997	383307
OMC	5.8L	All	4-Stroke	1994–1997	383307
OMC	5.8EFI	All	4-Stroke	1994–1997	383307	Electronic Fuel Injection model
OMC	All	All	4-Stroke	1980+	383307	2.5L & 3.0L, except 4-cylinder engines

Technical Specs

Product Type: Thermostat Kit
Installation: Direct OEM Replacement
Temperature Rating: 160°F (71°C)
Application: Raw Water Cooled Marine Engines
Housing Color: Silver/Metallic
Fitting Type: OEM-Compatible
Operating Temperature: 160°F (71°C) Opening Temperature
Production Standards: ISO9002 Certified Factory (JLM Marine)

What’s in the Box

1 x 160° Thermostat (Replaces 3856961)
1 x Gasket (Replaces 3852111)
1 x O-Ring (Replaces 3852071)

Installation Notes

Follow these general steps for thermostat replacement. Refer to your engine’s service manual for detailed instructions.

Disconnect the battery and allow the engine to cool completely.
Drain the engine coolant into a suitable container.
Locate the thermostat housing, typically where the main coolant hose connects to the engine.
Remove the bolts securing the housing cover. Note their orientation.
Carefully remove the old thermostat, gasket, and any O-rings.
Thoroughly clean the mating surfaces of the housing and cover, removing all old gasket material.
Install the new thermostat in the correct orientation, followed by the new gasket and O-ring.
Re-secure the housing cover and tighten bolts to the manufacturer’s specified torque.
Refill the cooling system with the appropriate coolant.
Reconnect the battery, start the engine, and check for leaks as it warms up to operating temperature.

Troubleshooting & FAQ

How do I know if my thermostat is failing?

Common signs of a faulty thermostat include engine overheating (stuck closed) or taking too long to reach operating temperature (stuck open). You may also notice erratic temperature gauge readings or coolant leaks around the housing.

Is a 160°F thermostat correct for my engine?

This 160°F thermostat is specified for the raw water-cooled marine engines listed. Using the correct temperature is critical for performance and engine health. Always replace it with a thermostat of the same rating.

Will this kit fit 4-cylinder Volvo Penta or OMC engines?

No, this particular kit is designed specifically for the V6 and V8 engine applications listed. Check the compatibility tables carefully.

How often should a marine thermostat be replaced?

For preventative maintenance, it is advisable to inspect your thermostat annually and replace it every 2-3 years, or immediately if you notice any signs of failure. This is especially important in saltwater environments.

Does this kit include everything needed for the job?

This kit includes the thermostat, gasket, and O-ring required for replacement. You will need your own tools, sealant (if specified by your service manual), and replacement coolant.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost?

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns?

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
This is an aftermarket replacement, not an OEM component.
Professional installation is recommended for safety and performance.

About Sea Sierra

Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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