We researched and compared the top sealants for valve cover gaskets using manufacturer specifications, industry standards, and aggregated owner feedback. Our evaluation focuses on performance, durability, ease of use, and safety to help you choose the right product for your engine repair.
| Photo | Product | Score | Buy |
|---|---|---|---|
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Permatex Ultra Black Maximum Oil Resistance RTV Silicone Gasket Maker Best Overall Sensor-safe, low odor, maximum oil resistance |
9.0 | 🛒 Check Price |
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Fel-Pro TBS 90014 Valve Cover Gasket Set with PermaDryPlus Gasket Best Complete Kit Includes gasket and sealant, nitrile rubber construction |
8.7 | 🛒 Check Price |
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Right Stuff Grey RTV Silicone Gasket Maker Fast Cure Cures in 1 hour, sensor-safe, high torque |
8.4 | 🛒 Check Price |
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Versachem 75089 Copper Spray-A-Gasket Sealant High Heat Copper formula, withstands 600 degrees F |
8.1 | 🛒 Check Price |
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Loctite 5910 Premium RTV Silicone Gasket Maker Flexible Seal Low volatility, flexible, sensor-safe |
7.8 | 🛒 Check Price |
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ThreeBond 1207B Silicone Gasket Maker OEM Grade OEM specified, high oil resistance |
7.5 | 🛒 Check Price |
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Permatex 82180 Ultra Copper RTV Silicone Gasket Maker High Temp Copper silicone, 500 degrees F intermittent |
7.3 | 🛒 Check Price |
1. Permatex Ultra Black Maximum Oil Resistance RTV Silicone Gasket Maker: Best Overall
Permatex Ultra Black is a top choice for valve cover gaskets based on our research. Manufacturer specs indicate it resists oil, transmission fluid, and antifreeze, with intermittent heat tolerance up to 500 degrees F. Owner feedback consistently praises its leak-proof seal on valve covers, even on high-mileage engines. It is sensor-safe and non-corrosive, meeting OEM standards for modern engines.
However, one limitation is the required 24-hour cure time before full oil pressure exposure, which may delay reassembly. If you need a faster cure, consider a different product. This sealant is best for those who prioritize oil resistance and can wait for proper curing.
- Withstands high temperatures up to 500 degrees F intermittent
- Resists oil, transmission fluid, and antifreeze
- Non-corrosive and sensor-safe for modern engines
Pros: Excellent oil resistance prevents leaks; Works well on valve covers and timing covers
Cons: Requires 24-hour cure for full strength
2. Fel-Pro TBS 90014 Valve Cover Gasket Set with PermaDryPlus Gasket: Best Complete Kit
Fel-Pro TBS 90014 is a complete valve cover gasket set with a pre-applied sealant layer. Our research shows the nitrile rubber gasket meets OEM specs for oil and heat resistance. Owner reviews highlight easy installation and long-lasting seals on common engines like Ford 4.6L and Chevy 5.3L.
However, the kit is designed for specific vehicle models, so compatibility must be checked. If your engine is not listed, you may need a universal sealant. This set is ideal for DIYers who want a hassle-free, matched solution.
- Pre-applied sealant layer for easy installation
- Designed to fit many domestic and import vehicles
- Includes valve cover bolts and grommets
Pros: Convenient all-in-one kit saves time; Gasket material resists oil and heat
Cons: Limited to specific vehicle applications
3. Right Stuff Grey RTV Silicone Gasket Maker: Fast Cure
Right Stuff Grey is known for its 1-hour cure time, as stated in manufacturer specs. Our evaluation of owner feedback confirms it seals valve covers effectively and allows quick reassembly. It is sensor-safe and resistant to oil, making it a solid choice for routine gasket replacements.
One reported limitation is that it can be less flexible than other RTVs, which may cause issues on surfaces with slight warping. If your valve cover has uneven surfaces, a more flexible sealant might be better. This product suits those who need a fast turnaround without sacrificing seal quality.
- Allows immediate oil fill and start-up after 1 hour
- Withstands continuous oil immersion
- Non-corrosive and low odor
Pros: Fast cure reduces downtime; Good oil resistance for valve covers
Cons: Slightly less flexible than some competitors
4. Versachem 75089 Copper Spray-A-Gasket Sealant: High Heat
Versachem Copper Spray-A-Gasket is a high-heat sealant spray designed for gaskets. According to the manufacturer, it withstands up to 600 degrees F, making it suitable for valve covers near exhaust manifolds. Owner feedback indicates it works well as a gasket dressing to prevent leaks on metal gaskets.
However, it is not meant to be used alone without a gasket, and overspray can be messy. Some users report it may dry out over time. This product is best for those using a separate gasket and needing extra heat protection.
- Spray-on application for even coverage
- Resists high heat and pressure
- Works on metal and composite gaskets
Pros: Excellent high-temperature tolerance; Easy to apply with spray nozzle
Cons: Not a standalone sealant; requires gasket
5. Loctite 5910 Premium RTV Silicone Gasket Maker: Flexible Seal
Loctite 5910 is a flexible RTV silicone designed for flanged joints like valve covers. Manufacturer data shows it is low volatility and sensor-safe. Based on owner reviews, it provides a reliable seal on engines with moderate vibration, and its flexibility helps prevent cracking.
One downside is the 24-hour cure time, similar to other RTVs. Some users note that it may not hold up as well under extreme oil pressure. If your engine has high oil pressure or you need faster cure, consider other options. This is a good choice for daily drivers where flexibility is key.
- Low odor and non-corrosive
- Good flexibility for thermal expansion
- Resists oil and coolant
Pros: Flexible seal accommodates engine movement; Easy to apply with caulking gun
Cons: Longer cure time (24 hours)
6. ThreeBond 1207B Silicone Gasket Maker: OEM Grade
ThreeBond 1207B is an OEM-grade silicone often specified by Japanese automakers. Our research indicates it meets strict manufacturer standards for oil resistance and durability. Owner feedback from import car forums confirms it seals valve covers effectively on Honda and Toyota engines.
However, it is more expensive than many aftermarket options, and its availability on Amazon can be limited. Some users report it has a shorter shelf life once opened. If you need an exact OEM match for a Japanese vehicle, this is a solid choice, but for general use, a more affordable RTV may suffice.
- Used by many Japanese manufacturers
- Resists engine oils and coolants
- Non-corrosive and sensor-safe
Pros: Trusted OEM quality; Works well on aluminum and steel
Cons: Higher cost per ounce
7. Permatex 82180 Ultra Copper RTV Silicone Gasket Maker: High Temp
Permatex Ultra Copper is designed for high-temperature applications. Manufacturer specs show it withstands up to 500 degrees F intermittent. Owner feedback indicates it works on valve covers near hot engine components, but some note that it may not hold up as well under continuous oil immersion compared to Ultra Black.
Its copper color can also stain surfaces, and it requires careful application. If your valve cover sees extreme heat from a turbo or exhaust, this sealant is worth considering. For standard oil resistance, Ultra Black is a better choice.
- High temperature resistance for turbo engines
- Sensor-safe and low odor
- Oil and coolant resistant
Pros: Handles high heat well; Good adhesion to metal surfaces
Cons: Not as oil-resistant as Ultra Black
Frequently Asked Questions
Do I need sealant on a valve cover gasket?
Many valve cover gaskets come with pre-applied sealant or are designed to be installed dry. However, using a small amount of RTV silicone at the corners and seams can prevent leaks, especially on engines with uneven surfaces. Always check the gasket manufacturer’s instructions.
What type of sealant is best for valve cover gaskets?
Oil-resistant RTV silicone gasket makers are best. Look for sensor-safe, low-odor formulas that resist engine oil and coolant. Products like Permatex Ultra Black or Right Stuff Grey are popular choices based on owner feedback and manufacturer specs.
Can I use regular silicone caulk for a valve cover gasket?
No, regular silicone caulk is not designed to withstand engine oil, heat, or pressure. It can degrade quickly and cause leaks. Always use an automotive-grade RTV silicone gasket maker specified for oil resistance.
How long should I let valve cover sealant cure before starting the engine?
Cure times vary by product. Most RTV silicones recommend 24 hours for full cure, but some like Right Stuff Grey allow engine start after 1 hour. Always follow the manufacturer’s instructions to ensure a proper seal.
Can I reuse a valve cover gasket after applying sealant?
It is not recommended to reuse a valve cover gasket once sealant has been applied, as the sealant bonds to the gasket and may not reseal properly. Always install a new gasket and fresh sealant for best results.
Our Verdict
Our top pick is Permatex Ultra Black for its superior oil resistance and proven owner satisfaction. For those seeking a complete kit with a gasket, Fel-Pro TBS 90014 is an excellent runner-up that simplifies installation.
