Powerhead Base Gasket – Fits Evinrude/Johnson 25-35HP Outboards (Replaces 0330621, 0324332)
Powerhead Base Gasket – Fits Evinrude/Johnson 25-35HP Outboards (Replaces 0330621, 0324332) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Powerhead Base Gasket – Fits Evinrude/Johnson 25-35HP Outboards (Re...
Product Details
This high-quality aftermarket Powerhead Base Gasket creates a reliable seal between the powerhead and midsection on a range of Evinrude and Johnson outboards. It is specifically designed for 25-35HP, 2-stroke models manufactured between 1979 and 1984, ensuring a precise fit and restoring engine integrity.
It serves as a direct replacement for multiple OEM and aftermarket part numbers, including Evinrude/Johnson 0330621 and 0324332, Sierra 18-2852, and Mallory 9-60445, offering a dependable alternative for engine rebuilds and maintenance.
- Installs between the powerhead and the upper midsection exhaust housing.
- Engineered from durable composite gasket material for a long-lasting seal.
- Meets or exceeds original equipment manufacturer (OEM) quality standards.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Evinrude/Johnson | 0330621 |
| Evinrude/Johnson | 0324332 |
| Evinrude/Johnson | 0777412 |
| Sierra Marine | 18-2852-9 |
| Sierra Marine | 18-2852 |
| GLM Marine | 33710 |
| Mallory Marine | 9-60445 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Evinrude Models: This gasket fits a wide variety of 25HP and 35HP 2-stroke outboards from 1979 through 1984. Please verify your specific model code (e.g., E25RCSA, E35ELCSM) against the list.
For Johnson Models: Compatible with numerous 25HP and 35HP 2-stroke outboards from the 1979–1984 model years. Check your motor's model number (e.g., J25RCSA, J35RLCIG) to ensure an exact match.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Evinrude | E25RCSA | 25 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Evinrude | E25RLCSA | 25 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Evinrude | E25TECSA | 25 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Evinrude | E25TELCSA | 25 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Evinrude | E25ECIB, E25ECIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Evinrude | E25ELCIB, E25ELCIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Evinrude | E25RCIM, E25RLCIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Evinrude | E25RSA, E25RSLA | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Evinrude | E25RWCIM, E25RWLCIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Evinrude | E25TECIM, E25TELCIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Evinrude | E25CNE, E25ELCNE | 25 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Evinrude | E25RCNB, E25RLCNB | 25 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Evinrude | E25TECNB, E25TELCNB | 25 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Evinrude | E25ECTD, E25ELCTD | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Evinrude | E25RCTE, E25RLCTE | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Evinrude | E25RSLS, E25RSS | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Evinrude | E25RWCTE, E25RWLCTE | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Evinrude | E25TECTE, E25TELCTE | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Evinrude | E25ECRS, E25ELCRS | 25 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Evinrude | E25RCRD, E25RLCRD | 25 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Evinrude | E25RWCRD, E25RWLCRD | 25 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Evinrude | E25TECRD, E25TELCRD | 25 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Evinrude | E30ECRR, E30ELCRR | 30 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Evinrude | 25904R, 25905R, 25952R, 25953R | 25 | 2-Stroke | 1979 | 0330621 | Replaces 0324332 |
| Evinrude | 35902A, 35903A, 35952A, 35953A | 35 | 2-Stroke | 1979 | 0330621 | Replaces 0324332 |
| Evinrude | E35ECSM, E35ELCSM | 35 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Evinrude | E35TCSM, E35TLESM | 35 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Evinrude | E35ECIG, E35ELCG | 35 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Evinrude | E35RCIG, E35RLCIG | 35 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Evinrude | E35ECND, E35ELCND | 35 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Evinrude | E35RCND, E35RLCND | 35 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Evinrude | E35TELCNB | 35 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Evinrude | E35ECTS, E35ELCTS | 35 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Evinrude | E35RCTS, E35RLCTS | 35 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Evinrude | E35TELCTS | 35 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Evinrude | E35ECRR, E35ELCRR | 35 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Evinrude | E35RCRR, E35RLCRR | 35 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Evinrude | E35TELCRR | 35 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Johnson | 25E79R, 25EL79R, 25R79R, 25RL79R | 25 | 2-Stroke | 1979 | 0330621 | Replaces 0324332 |
| Johnson | J25RCSA, J25RLCSA | 25 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Johnson | J25TECSA, J25TELCSA | 25 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Johnson | J25ECIB, J25ECIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Johnson | J25ELCIB, J25ELCIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Johnson | J25RCIM, J25RLCIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Johnson | J25RSA, J25RSLA | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Johnson | J25RWCIM, J25RWLCIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Johnson | J25TECIM, J25TELCIM | 25 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Johnson | J25ECNE, J25ELCNE | 25 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Johnson | J25RCNB, J25RELCNB, J25RLCNB | 25 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Johnson | J25TECNB | 25 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Johnson | J25ECTD, J25ELCTD | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Johnson | J25RCTE, J25RLCTE | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Johnson | J25RSLS, J25RSS | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Johnson | J25RWCTE, J25RWLCTE | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Johnson | J25TECTE, J25TELCTE | 25 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Johnson | J25ECRS, J25ELCRS | 25 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Johnson | J25RCRD, J25RLCRD | 25 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Johnson | J25RWCRD, J25RWLCRD | 25 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Johnson | J25TECRD, J25TELCRD | 25 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Johnson | J30ECRR, J30ELCRR | 30 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Johnson | 35E79A, 35EL79A, 35R79A, 35RL79A | 35 | 2-Stroke | 1979 | 0330621 | Replaces 0324332 |
| Johnson | J35ECSM, J35ELCSM | 35 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Johnson | J35RCSM, J35RLCSM | 35 | 2-Stroke | 1980 | 0330621 | Replaces 0324332 |
| Johnson | J35ECIG, J35ELCIG | 35 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Johnson | J35RCIG, J35RLCIG | 35 | 2-Stroke | 1981 | 0330621 | Replaces 0324332 |
| Johnson | J35ECND, J35ELCND | 35 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Johnson | J35RCND, J35RLCND | 35 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Johnson | J35TELCNB | 35 | 2-Stroke | 1982 | 0330621 | Replaces 0324332 |
| Johnson | J35ECTS, J35ELCTS | 35 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Johnson | J35RCTS, J35RLCTS | 35 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Johnson | J35TELCTS | 35 | 2-Stroke | 1983 | 0330621 | Replaces 0324332 |
| Johnson | J35ECRR, J35ELCRR | 35 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Johnson | J35RCRR, J35RLCRR | 35 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
| Johnson | J35TELCRR | 35 | 2-Stroke | 1984 | 0330621 | Replaces 0324332 |
Technical Specs
- Product Type
- Powerhead Base Gasket
- Installation
- Between powerhead and midsection
- Dimensions
- 23.0 cm × 18.0 cm × 0.5 cm
- Weight
- 150 g (0.33 lb)
- Material
- Gasket paper/composite
- Other Technical Attributes
- Original Equipment Manufacturer (OEM) quality
What’s in the Box
- 1 x Powerhead Base Gasket (0330621)
Installation Notes
- Disconnect the battery and all electrical connections to the powerhead.
- Drain engine coolant and disconnect fuel lines.
- Systematically loosen and remove the powerhead mounting bolts.
- Carefully lift the powerhead off the midsection. Assistance may be required.
- Remove the old gasket and thoroughly clean both mating surfaces of any residue.
- Position the new gasket, ensuring all bolt holes and passages align perfectly.
- Lower the powerhead back into place and hand-tighten the bolts.
- Torque all bolts to the manufacturer's specified sequence and values.
- Reconnect fuel lines, electrical connections, and refill coolant.
- Start the engine and carefully check for any exhaust or fluid leaks around the gasket.
Troubleshooting & FAQ
How do I know if my powerhead gasket has failed?
Common signs of a failed powerhead base gasket include visible exhaust or water leaks between the powerhead and the midsection, a loss of engine compression, poor idling, or overheating. A physical inspection for residue or damage in the gasket area is the best diagnostic step.
Is any sealant required with this gasket?
Generally, this type of gasket is designed to be installed dry. Applying sealant can sometimes interfere with proper seating and cause future leaks. Always consult your service manual, but in most cases, a clean, dry installation is recommended.
Can I reuse my old powerhead gasket?
No. Gaskets are single-use components that crush to create a unique seal. Once the powerhead is removed, the old gasket loses its integrity and must be replaced to ensure a leak-free and reliable repair.
What is the main cause of powerhead gasket failure?
Failures are often caused by engine overheating, which can warp the aluminum mating surfaces, or by improper torque on the powerhead bolts (either too loose or too tight). Age and material degradation from exposure to fuel, oil, and saltwater are also contributing factors.
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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