Cylinder Head Gasket – Fits Suzuki DT40 40HP Outboard Engine (Replaces 11141-94450, 11141-94400)

$14.00 $22.00

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Cylinder Head Gasket – Fits Suzuki DT40 40HP Outboard Engine (Replaces 11141-94450, 11141-94400) is backordered and will ship as soon as it is back in stock.

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Product Details

This replacement Cylinder Head Gasket – Fits Suzuki DT40 40HP Outboard Engine is engineered for Suzuki DT40 40HP 2-stroke outboard motors manufactured between 1986–1999, including DT40C, DT40W, DT40G, and DT40X models.

It serves as a direct interchange for Suzuki part numbers 11141-94450, 11141-94440, and their variants, as well as Sierra 18-3810.

Installs as a direct replacement for the OEM gasket.
Constructed from durable steel and asbestos-free materials.
Designed for 2-cylinder, 2-stroke engine configurations.

Part Number Matrix

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

Brand	Part Number
Suzuki	11141-94450
Suzuki	11141-94450-000
Suzuki	11141-94440
Suzuki	11141-94441
Suzuki	11141-94401
Suzuki	11141-94410
Suzuki	11141-94420
Suzuki	11141-94430
Sierra	18-3810

Engine & Model Compatibility

Confirm your engine model and year in the table below. This gasket is specifically designed for Suzuki's two-cylinder DT40 series engines produced from 1986 through 1999.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.
Suzuki	DT40C	40	2-Stroke	1986–1999	11141-94450
Suzuki	DT40W	40	2-Stroke	1986–1999	11141-94450
Suzuki	DT40G	40	2-Stroke	1986–1999	11141-94450
Suzuki	DT40X	40	2-Stroke	1986–1999	11141-94450

Technical Specs

Product Type: Cylinder Head Gasket
Installation: Direct replacement for OEM gasket
Fuel Type: Gasoline
Housing Material: Steel & Asbestos-free Material
Dimensions: 11.0" L x 5.75" W x 0.13" H
Configuration: For 2-cylinder, 2-stroke engines

What’s in the Box

1 x Cylinder Head Gasket (Replaces 11141-94450-000)

Installation Notes

For a successful installation, please follow these general steps. Refer to your official service manual for detailed procedures and torque specifications.

Disconnect the battery and drain the engine's cooling system.
Remove the engine cowling and any components obstructing access to the cylinder head.
Carefully disconnect all electrical wiring, fuel lines, and linkages attached to the head.
Loosen and remove the cylinder head bolts in the sequence specified by the manufacturer to prevent warping.
Lift the cylinder head off the engine block and remove the old head gasket.
Thoroughly clean both the cylinder head and engine block surfaces, ensuring they are free of old gasket material and debris.
Position the new gasket correctly on the engine block; check for proper alignment with dowel pins.
Carefully place the cylinder head back onto the block over the new gasket.
Install and tighten the head bolts in the correct sequence and to the specified torque values.
Reassemble all previously removed components, including manifolds, wiring, and fuel lines.
Refill the cooling system and reconnect the battery before starting the engine.
Check for leaks and ensure the engine operates smoothly.

Troubleshooting & FAQ

How do I confirm this gasket fits my Suzuki DT40?

This gasket is designed for Suzuki DT40 models (DT40C, DT40W, DT40G, DT40X) from 1986–1999. Verify your model and year fall within this range. Cross-reference your existing part number with those listed in our Part Number Matrix to ensure an exact match.

What are common signs of a failed head gasket?

Symptoms of a bad head gasket include engine overheating, loss of power, white smoke from the exhaust (coolant burning), milky or foamy engine oil (oil-coolant mixing), or external coolant/oil leaks from the engine head seam.

Do I need to use sealant with this gasket?

This gasket is designed to be installed dry. Do not use any additional sealants, adhesives, or gasket makers unless explicitly specified in your engine's service manual for your particular application.

How is this aftermarket gasket different from the OEM part?

Our gasket is engineered to meet or exceed OEM specifications for fit, form, and function. It is made from comparable high-quality, asbestos-free materials to ensure a reliable seal and long service life at a more competitive price point.

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 and specifications against your original part before purchase. If anything differs—even if your model is listed as compatible—do not complete the purchase.
This is an aftermarket replacement component, not an original equipment manufacturer (OEM) part.
Professional installation is highly recommended to ensure safety, proper fitment, and optimal performance.

About Sea Sierra

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