Parts for your 2017 Nissan Serena-Oil cap

2017 Nissan Serena Oil Cap — Purpose, Care and When to Replace

Yes, the 2017 Nissan Serena (C27) uses an engine oil filler cap. Technical sources including the Nissan Serena C27 Owner’s Manual (Engine compartment overview) and the Nissan Service Manual for the MR20DD engine (Engine Mechanical and Lubrication sections) identify and illustrate the oil filler cap on the cam cover. The Serena’s S-HYBRID system still pairs with a conventional petrol engine, so an oil cap is absolutely part of the package.

The oil cap seals the top of the engine where oil is added. Its job is simple but critical: it keeps engine oil from splashing out, stops dust and moisture getting in, and helps maintain the correct crankcase pressure for the PCV/breathing system. A loose, missing or perished cap can lead to oil mist around the engine bay, a whiff of burnt oil under the bonnet, and in some cases rough running due to unmetered air entering through the filler neck.

As part of routine servicing on a 2017 Serena, the oil cap deserves a quick once-over. After an oil change, make sure it’s seated squarely and tightened by hand until it’s snug—no need to crank on it. Wipe the sealing surface clean, and check the rubber O-ring or gasket for flattening, cracks or hardening. If the seal looks tired, replace the cap or the seal (if it’s a serviceable type). It’s cheap insurance against leaks and mess.

Daily driving in Aussie or Kiwi conditions—heat, dust, short trips—can be tough on seals. If there’s oil weeping around the filler area, if the cap feels loose or notchy, or if there’s a persistent oil smell after drives, it’s time to swap it. Choose a genuine Nissan cap or a quality equivalent that matches the MR20DD engine profile, avoid generic caps that don’t lock positively or sit proud of the cover. Driving without a cap is a no-go—oil can splash out quickly and contamination can find its way in.

• Check the cap at every service or ~10,000 km.
• Clean and inspect the O-ring, replace at the first sign of wear.
• After topping up oil, confirm the cap clicks/seats firmly.
• If the cap is dropped in dirt or sand, clean thoroughly before refitting.

These steps line up with practices shown in Nissan’s C27 MR20DD service literature and the owner’s manual guidance around lubrication and engine bay checks.

FAQs

Where is the oil cap on a 2017 Nissan Serena?

It’s under the bonnet on the top of the engine, usually front-right or centre depending on market orientation, with an oil-can symbol. On the MR20DD it sits on the cam/rocker cover and twists off by hand.

What are the signs the oil cap needs replacing?

Look for oil mist or wetness around the filler area, a fuel/oil odour after drives, a cap that won’t tighten cleanly, or a flattened/cracked O-ring. Any of these are a cue to replace the cap or seal.

Is it safe to drive if the oil cap is missing or broken?

No. Without a proper cap, oil can splash out and dirt can get in, risking engine damage. If the cap is missing, fit a correct replacement before driving any distance.