Looking for the best oil reservoir caps? We’ve tested and reviewed the top 10 options to help you find the perfect match for your engine.
Oil reservoir caps are small but vital parts for your engine. They keep oil in and dirt out, helping your engine run smoothly. Choosing the right one can save you time and money.
We’ve tested and reviewed the best oil reservoir caps for you. These caps fit many engines and are easy to install. They come with great features like tight seals and durable materials.
Whether you need a cap for a boat, car, or truck, we’ve got you covered. Our guide makes it simple to find the perfect match. Let’s get started!
List of Top 10 Oil Reservoir Caps
| Image | Title | Best For | Price |
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sevencow Oil Reservoir Cap Assembly for Mercury Outboard 105 135 140 150 175 200 210 225 240HP EFI PRO MAX M2 Blackmax Sport For Jet Boat XR2 XR4 XR6 V‑6 replace 36-43300A9 43300A1 |
This is perfect for Mercury outboard owners who want a safe, smooth engine run. It’s great for anyone who needs a quick, simple fix for a worn oil cap. |
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ÜREL Hydraulic Tank Breather Cap for Oil & Fuel Reservoir – Metal Filler Vent Cap (with Flange, Bayonet Lock, Chrome Plated, Tearproof Gasket) |
This ÜREL Hydraulic Tank Breather Cap is perfect for anyone who needs a reliable and durable solution for their oil or fuel reservoir. It’s ideal for indoor equipment and stationary power units, offering long-lasting protection and easy installation. |
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A.A Trim Pump Reservoir Oil Cap for MerCruiser 36-865448A01 |
This A.A Trim Pump Reservoir Oil Cap is perfect for boat owners who need a reliable replacement for their MerCruiser trim pump. It’s easy to install and fits perfectly, saving you time and hassle. |
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80991 Engine Oil Filler Cap Compatible with Select Ford/Lincoln/Mercury Models, fit for F250 F350 F450 E150 E250 E350 Ranger Mustang Explorer Taurus Windstar Grand Marquis, EP5Z-6766-A, EC-787 |
This cap is a perfect fit for Ford, Lincoln, and Mercury owners. It stops leaks and keeps oil in your engine. It is easy to use. It saves time. Your car stays clean. Keep your ride safe with this part. |
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Quicksilver 8067271 Gear Lube Monitor Reservoir Cap |
This cap is for boat owners. It fits Alpha and Bravo drives. It is easy to install. Twist it on by hand. Read your manual to use it. |
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A.A Oil Reservoir Cap Assembly Replacement for Mercury Quicksilver 1976-2005, 36-43300A9 |
This oil cap assembly is perfect for anyone who wants their Mercury outboard to run smooth and stay safe. It’s great for boat owners who need a simple, reliable replacement that fits engines from 105HP to 225HP. |
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Quicksilver Mercury Cap Oil Reservoir |
This Quicksilver Mercury Cap Oil Reservoir is perfect for boat owners who want to keep their engines running smoothly. It’s easy to install and fits specific Mercruiser models, making it a reliable choice for maintenance. |
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Dorman 84111 Engine Oil Filler Cap Compatible with Select Lexus/Scion/Toyota Models |
This oil cap is for Toyota or Lexus cars. It is easy to use and fits well. |
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Oil Reservoir Cap Assembly Replacement for Mercury Quicksilver 105, 135, 140, 150, 175, 200, 225, 240 HP for SportJet XR2 XR4 XR6 V‑6#36-43300A9 |
This cap assembly is perfect for boat owners. It fits Mercury and Quicksilver motors. |
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36-43300A9 43300A1 Oil Reservoir Cap For Mercury Mariner 43300A5 43300A6 Outboard 105 JET 135 140 150 175 200 210 225 240 HP EFI PRO MAX M2 Blackmax Ssportjet Boat XR2 XR4 XR6 V‑6 |
This part is perfect for boat owners who want a strong, reliable oil reservoir cap for their Mercury or Mariner motor. It suits anyone who needs a simple, safe, and steady fit for their V‑6 outboard. |
Detailed Reviews
Discover the top 10 Oil Reservoir Caps in our expert-curated guide. Each product is thoroughly reviewed for performance, durability, and value. Whether you need a reliable replacement or a high-quality upgrade, this guide has you covered. Find the perfect fit for your engine and enjoy peace of mind with our trusted recommendations.
1. sevencow Oil Reservoir Cap Assembly for Mercury Outboard 105 135 140 150 175 200 210 225 240HP EFI PRO MAX M2 Blackmax Sport For Jet Boat XR2 XR4 XR6 V‑6 replace 36-43300A9 43300A1
This oil cap fits many Mercury engines. It keeps your engine safe. It works with key EFI and V‑6 models.
It replaces old caps and worn parts. It includes the float, gasket, cap, nut, and wiring.
It is easy to install and simple to use. You also get a 30‑day refund for peace of mind.
| Pros | Cons |
|---|---|
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Perfect For:
This is perfect for Mercury outboard owners who want a safe, smooth engine run. It’s great for anyone who needs a quick, simple fix for a worn oil cap.
Ready to Purchase?
2. ÜREL Hydraulic Tank Breather Cap for Oil & Fuel Reservoir – Metal Filler Vent Cap (with Flange, Bayonet Lock, Chrome Plated, Tearproof Gasket)
The ÜREL Hydraulic Tank Breather Cap is a high-quality solution for your oil and fuel reservoirs. It’s made with a sleek chrome finish that looks great and fights corrosion. This cap is perfect for indoor equipment and stationary power units.
It has a tear-resistant gasket that lasts a long time. The 40-micron filter keeps out dirt and particles. This ensures your system stays clean and works well.
The complete installation kit includes everything you need. It has a mounting flange and screws for easy setup. This cap is built to last and perform at its best.
| Pros | Cons |
|---|---|
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Perfect For:
This ÜREL Hydraulic Tank Breather Cap is perfect for anyone who needs a reliable and durable solution for their oil or fuel reservoir. It’s ideal for indoor equipment and stationary power units, offering long-lasting protection and easy installation.
Ready to Purchase?
3. A.A Trim Pump Reservoir Oil Cap for MerCruiser 36-865448A01
The A.A Trim Pump Reservoir Oil Cap is a must-have replacement for your MerCruiser. It fits perfectly and replaces part # 36-865448A01. This yellow cap is easy to spot and use.
This oil reservoir cap is a direct replacement, ensuring a perfect fit and reliable performance. It’s a simple fix to keep your boat running smoothly.
| Pros | Cons |
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Perfect For:
This A.A Trim Pump Reservoir Oil Cap is perfect for boat owners who need a reliable replacement for their MerCruiser trim pump. It’s easy to install and fits perfectly, saving you time and hassle.
Ready to Purchase?
4. 80991 Engine Oil Filler Cap Compatible with Select Ford/Lincoln/Mercury Models, fit for F250 F350 F450 E150 E250 E350 Ranger Mustang Explorer Taurus Windstar Grand Marquis, EP5Z-6766-A, EC-787
This engine oil filler cap fits many Ford, Lincoln, and Mercury cars and trucks. It is a direct replacement for part numbers EP5Z-6766-A, EC-787, and 80991.
It is made from high quality material that lasts. Every cap is 100% inspected and tested before shipping. You get a durable and reliable part.
The cap is easy to install with no tools needed. If it ever cracks or fails, you get a replacement or refund. Our 12-month warranty and fast service protect your buy.
| Pros | Cons |
|---|---|
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Perfect For:
This cap is a perfect fit for Ford, Lincoln, and Mercury owners. It stops leaks and keeps oil in your engine. It is easy to use. It saves time. Your car stays clean. Keep your ride safe with this part.
Ready to Purchase?
5. Quicksilver 8067271 Gear Lube Monitor Reservoir Cap
This cap fits your gear lube monitor. It replaces worn or lost parts. It keeps your MerCruiser system safe.
It works with Alpha and Bravo sterndrives. It installs fast by hand.
This cap stays tight and secure. It helps you check gear lube with ease. It gives your engine steady protection.
| Pros | Cons |
|---|---|
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Perfect For:
This cap is for boat owners. It fits Alpha and Bravo drives. It is easy to install. Twist it on by hand. Read your manual to use it.
Ready to Purchase?
6. A.A Oil Reservoir Cap Assembly Replacement for Mercury Quicksilver 1976-2005, 36-43300A9
The A.A Oil Reservoir Cap Assembly is a direct replacement for Mercury Quicksilver models from 1976 to 2005. It fits specific outboard engines, ensuring a perfect match. This part is easy to install and built to last.
It replaces part numbers 36-43300A9 and 43300A9, making it a reliable choice. The package includes one oil reservoir cap assembly, ready for immediate use. This cost-effective solution keeps your engine running smoothly.
Compatible with Mercury Outboards ranging from 105HP to 225HP, it’s a must-have for maintenance. Trust this assembly to protect your engine and prevent leaks.
| Pros | Cons |
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Perfect For:
This oil cap assembly is perfect for anyone who wants their Mercury outboard to run smooth and stay safe. It’s great for boat owners who need a simple, reliable replacement that fits engines from 105HP to 225HP.
Ready to Purchase?
7. Quicksilver Mercury Cap Oil Reservoir
The Quicksilver Mercury Cap Oil Reservoir is a must-have for your boat’s engine. It fits Mercruiser models and keeps your engine running smoothly. This part is easy to install.
With the Quicksilver – Mercruiser 36-865448A01, you get reliable performance. It prevents oil leaks and ensures your engine stays well-lubricated. This cap is durable and built to last.
Keep your boat’s engine in top shape with this essential part. It’s simple to use and works great.
| Pros | Cons |
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Perfect For:
This Quicksilver Mercury Cap Oil Reservoir is perfect for boat owners who want to keep their engines running smoothly. It’s easy to install and fits specific Mercruiser models, making it a reliable choice for maintenance.
Ready to Purchase?
8. Dorman 84111 Engine Oil Filler Cap Compatible with Select Lexus/Scion/Toyota Models
This oil cap gives your engine the safe seal it needs. It fits select Lexus, Scion, and Toyota models with ease.
It is simple, strong, and steady. It locks tight. It lasts long.
This cap helps your car run right. It is built from quality parts for long life.
| Pros | Cons |
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Perfect For:
This oil cap is for Toyota or Lexus cars. It is easy to use and fits well.
Ready to Purchase?
9. Oil Reservoir Cap Assembly Replacement for Mercury Quicksilver 105, 135, 140, 150, 175, 200, 225, 240 HP for SportJet XR2 XR4 XR6 V‑6#36-43300A9
This oil reservoir cap assembly keeps your engine safe. It gives clear oil level signals. It locks in place with a tight, clean seal.
It fits many Mercury Quicksilver engines. It helps restore correct oil warnings.
This cap is simple to install. It works fast and smooth. It brings back steady oil checks.
| Pros | Cons |
|---|---|
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Perfect For:
This cap assembly is perfect for boat owners. It fits Mercury and Quicksilver motors.
Ready to Purchase?
10. 36-43300A9 43300A1 Oil Reservoir Cap For Mercury Mariner 43300A5 43300A6 Outboard 105 JET 135 140 150 175 200 210 225 240 HP EFI PRO MAX M2 Blackmax Ssportjet Boat XR2 XR4 XR6 V‑6
This cap fits your Mercury or Mariner oil reservoir. It locks tight to help keep your engine safe. It works with many V‑6 outboards from 105 to 225 HP.
You get a 1‑year warranty for peace of mind. It matches several 43300A‑series parts for easy use.
| Pros | Cons |
|---|---|
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Perfect For:
This part is perfect for boat owners who want a strong, reliable oil reservoir cap for their Mercury or Mariner motor. It suits anyone who needs a simple, safe, and steady fit for their V‑6 outboard.
Ready to Purchase?
Buying Guide
Oil reservoir caps are small but vital for your engine. They keep oil in and dirt out, helping your engine run smoothly.
Choosing the right cap can save you time and money. We’ve tested and reviewed the best oil reservoir caps to make your decision easy.
Here’s what to consider when buying:
- Compatibility: Make sure the cap fits your engine model. Check the make, model, and year of your vehicle or boat.
- Material: Look for durable materials like metal or high-quality plastic. They last longer and resist corrosion.
- Seal Quality: A tight seal prevents leaks and keeps dirt out. Choose caps with tear-resistant gaskets.
- Ease of Installation: Pick caps that are easy to install. Some come with complete kits for hassle-free setup.
- Warranty: A warranty gives you peace of mind. Look for options with refunds or replacements.
- Price: Compare prices to find the best value. Quality caps don’t have to break the bank.
- Features: Extra features like filters or chrome finishes can add value. Choose what suits your needs.
With these tips, you’ll find the perfect oil reservoir cap for your engine. Let’s keep your engine running smoothly!