Cylinder Head Gasket – Fits Volvo Penta AQ120B, AQ125A, AQ140A & BB140A (Replaces 1378645, 463412)
Cylinder Head Gasket – Fits Volvo Penta AQ120B, AQ125A, AQ140A & BB140A (Replaces 1378645, 463412) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Cylinder Head Gasket – Fits Volvo Penta AQ120B, AQ125A, AQ140A &...
Product Details
This Cylinder Head Gasket is engineered for 4-cylinder Volvo Penta gasoline marine engines (110–125 HP) manufactured between 1975 and 1984. It ensures a precise fit for models including the AQ120B, AQ125A, AQ140A, and BB140A series.
It serves as a direct aftermarket replacement for Volvo Penta part numbers 1378645 and 463412, as well as Sierra 18-2968 and Orbitrade 13645.
- Installs between the engine block and cylinder head.
- Purpose-built for the demands of marine gasoline engine environments.
- Creates a robust seal to ensure maximum compression and prevent coolant or oil leaks.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Volvo Penta | 1378645 |
| Volvo Penta | 463412 |
| Sierra | 18-2968 |
| Orbitrade | 13645 |
Engine & Model Compatibility
Confirm your engine model and year in the table below to ensure correct fitment.
For Volvo Penta engines:
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. |
|---|---|---|---|---|---|
| Volvo Penta | AQ120B | 110 | 4-Stroke | 1977–1980 | 1378645, 463412 |
| Volvo Penta | AQ125A | 117 | 4-Stroke | 1981–1984 | 1378645, 463412 |
| Volvo Penta | AQ140A | 125 | 4-Stroke | 1975–1979 | 1378645, 463412 |
| Volvo Penta | BB140A | 125 | 4-Stroke | 1975–1979 | 1378645, 463412 |
Technical Specs
- Product Type
- Cylinder Head Gasket
- Installation Location
- Between engine block and cylinder head
- Fuel Type
- Gasoline
- Application
- Marine engines
- Dimensions (L×W×H)
- 44.5 × 16.0 × 0.4
- Purpose
- Ensures maximum compression and prevents leaks of oil or coolant into cylinders
- OEM Reference
- Volvo Penta 1378645, 463412
What’s in the Box
- 1 x Cylinder Head Gasket (Replaces 1378645/463412)
Installation Notes
- Ensure the engine is completely cool and disconnect the battery before starting.
- Drain the engine oil and coolant from the system to prevent spills during disassembly.
- Carefully remove the cylinder head, following your engine’s service manual for the correct bolt loosening sequence.
- Thoroughly clean both the engine block and cylinder head mating surfaces. All old gasket material, sealant, and debris must be removed.
- Inspect both surfaces for warping, cracks, or damage. They must be perfectly flat and clean for a proper seal.
- Position the new head gasket correctly on the engine block, ensuring it is properly oriented. Do not use sealant unless specified by the engine manufacturer.
- Carefully reinstall the cylinder head. Torque the head bolts to the manufacturer's specified values and in the correct sequence.
- Reconnect all hoses, sensors, and components. Refill the engine with fresh oil and coolant.
- After reconnecting the battery, start the engine and carefully inspect for any signs of leaks.
Troubleshooting & FAQ
How do I know if this gasket fits my engine?
Please refer to the "Engine & Model Compatibility" table on this page. This gasket is specifically for Volvo Penta 4-cylinder gasoline models from 1975–1984, such as the AQ120B and AQ125A. Double-check that your exact model and year are listed.
What are common signs of a failed head gasket?
Telltale signs include engine overheating, dense white smoke from the exhaust (indicating coolant burn), milky or foamy engine oil, unexplained coolant loss, or a noticeable loss of compression and engine power.
Do I need to use sealant with this gasket?
In most applications, this type of composite gasket is designed to be installed dry. However, you should always defer to the instructions in your engine’s official service manual, as some specific models may have different requirements.
When should a cylinder head gasket be replaced?
Head gaskets do not have a standard replacement interval. They are typically replaced only when they fail or as part of a larger engine rebuild. If you observe any symptoms of failure, replacement is necessary.
Is this an OEM part or aftermarket?
This listing is for an aftermarket replacement, not an OEM part. It is built to meet or exceed OEM-level specifications using comparable materials. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected for quality and consistency.
What are the shipping speed and cost?
We ship worldwide quickly—typical transit time is 5–15 days for most regions. Standard shipping is free, and expedited options will appear at checkout if they are available for your location.
What is the warranty and return policy?
This part is covered by a 1-year warranty against manufacturing defects under normal marine use. If an issue arises, contact our support team with your order details. Returns are accepted within our standard window, provided the item is unused and in its original packaging. Please see our full policy page or contact us for instructions.
Safety & Important Info
- Verify all images and specifications against your original part before ordering. If anything differs—even if your model appears on the compatibility list—do not purchase.
- This is an aftermarket replacement component, not an Original Equipment Manufacturer (OEM) part.
- Professional installation is highly recommended for safety, proper fitment, and optimal engine performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to strict OEM-level tolerances and rigorously tested for demanding real-world conditions.
- Fast Global Fulfillment — We offer free standard delivery to most regions worldwide, with typical transit times of just 5–15 days.
- Manufacturer-Direct Value — By working directly with our manufacturing partners, we provide fair pricing without ever compromising on materials or quality control.
Payment & Security
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