Thermostat Kit – Fits Volvo Penta 3.0L 1996-Up (Replaces 3853799, 982554, 3852096)

$26.49

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Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This Thermostat Kit – Fits Volvo Penta 3.0L 1996-Up (Replaces 3853799, 982554, 3852096) is a direct replacement for Volvo Penta 3.0L stern drive engines manufactured from 1996 and onward, covering GLP, GLM, GSP, and GSM models. It ensures your engine maintains the correct operating temperature for optimal performance and longevity.

This kit serves as a direct interchange for Sierra 18-3621, JLM Marine 3853799, FASWORX 3853799, and Czomoizc 3853799.

Installs as a direct OEM-equivalent replacement.
Maintains proper engine operating temperature at a 160°F (71°C) rating.
Includes the thermostat, gasket, and O-ring for a complete service.

Part Number Matrix

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

Brand	Part Number
Volvo Penta	3853799
Sierra	18-3621
JLM Marine	3853799
FASWORX	3853799
Czomoizc	3853799

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Volvo Penta engines, check your model, year, and any specific version notes or engine IDs to ensure a match.

Brand	Model	Stroke	Years	OEM Part No.	Notes
Volvo Penta	3.0L GL	4-Stroke	1996–2000	3853799	Engine IDs: LK, BY, WT, EF
Volvo Penta	3.0L GSP	4-Stroke	1996–2000	3853799	Engine IDs: LK, BY, WT, EF
Volvo Penta	3.0L GLP	4-Stroke	1996–2000	3853799	Engine IDs: LK, BY, WT, EF
Volvo Penta	3.0L GLM	4-Stroke	1996–2000	3853799	Engine IDs: LK, BY, WT, EF
Volvo Penta	3.0L GLP	4-Stroke	2000–Up	3853799	Versions A, B, C, D, E, J
Volvo Penta	3.0L GLM	4-Stroke	2000–Up	3853799	Versions A, B, C, D, E, J
Volvo Penta	3.0L GSP	4-Stroke	2000–Up	3853799	Versions A, B, C, D, E, J
Volvo Penta	3.0L GSM	4-Stroke	2000–Up	3853799	Versions A, B, C, D, E, J

Technical Specs

Product Type: Thermostat Kit
Installation: Direct OEM Replacement
Template Rating: 160°F (71°C)
Operating Temperature: 160°F (71°C)
Other Technical Attributes: Maintains proper engine operating temperature
Warranty: Varies by manufacturer

What’s in the Box

1 x Thermostat (3853799)
1 x Gasket (3852096)
1 x O-Ring (982554)

Installation Notes

Disconnect the battery before starting work.
Drain the engine coolant to a level below the thermostat housing.
Carefully remove the hoses connected to the thermostat housing.
Unbolt and remove the thermostat housing cover.
Take out the old thermostat, gasket, and O-ring. Note their orientation before removal.
Thoroughly clean the mating surfaces of the housing and cover, removing any old gasket material.
Install the new thermostat, ensuring it is seated correctly in the housing according to the manufacturer's direction.
Place the new gasket and O-ring into position to ensure a perfect seal.
Reinstall the housing cover and tighten the bolts to the engine manufacturer's specified torque.
Reconnect the hoses and secure the clamps.
Refill the cooling system with the appropriate type and amount of coolant.
Reconnect the battery, start the engine, and check for any leaks as it warms to its operating temperature.

Troubleshooting & FAQ

How do I know if my thermostat is failing?

Common signs include engine overheating, running too cool (low temp gauge reading), erratic temperature fluctuations, and coolant leaks around the thermostat housing.

Will this fit my specific Volvo Penta 3.0L model?

This kit is designed for Volvo Penta 3.0L engines from 1996 and newer. Please verify your exact model and year against our compatibility table and check for any engine ID or version notes to confirm fitment.

What is the correct operating temperature for my engine?

This is a 160°F (71°C) rated thermostat, which is the standard operating temperature for these engines to ensure optimal performance, fuel efficiency, and engine longevity.

How often should I replace my marine thermostat?

As a preventative maintenance measure, marine thermostats should be inspected annually and replaced every 2-3 years or as part of routine cooling system service, even if they have not yet failed.

Can I install just the thermostat without the new gasket and O-ring?

No. It is critical to replace the gasket and O-ring during installation to ensure a proper seal and prevent coolant leaks, which could lead to engine damage. This kit includes all necessary components.

What are the signs of using a thermostat with the wrong temperature rating?

Using a thermostat that is too hot can lead to overheating, while a thermostat that is too cool can cause poor fuel economy, carbon buildup, and reduced engine performance. Always use the temperature rating specified for your engine.

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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