Yamalube 20W-40 4-Stroke Outboard Motor Oil

Yamaha 20W-40 4M Marine Engine Oil Resources and Information

PartsVu.com is happy to offer a broad selection of Yamalube 20W-40 4-stroke outboard engine oil to match your Yamaha outboard specifications. Our inventory of Yamajlube 20W-40 4-stroke outboard motor oil comes in quantities of quarts and gallons, as well as multipacks, to help you save money by buying in bulk. 

We stock a complete range of Yamaha outboard parts to service your Yamaha outboard engine. Looking for other Yamaha outboard engine oils? Browse our selection of 4m and 2m certified Yamaha OEM outboard motor oils.

We also regularly release new, helpful resources like:

• Yamaha Outboard Specs & Capacities Chart
• Yamaha Outboard Service Schedule

Yamalube 20W-40 4-Stroke Outboard Motor Oil

How do I perform an oil change on my Yamaha 4-stroke outboard motor?

If your Yamaha 4-stroke outboard motor features oil injection with a remote oil tank inside the boat, you will begin your service by accessing this tank. These remote tanks are not always situated in the easiest-to-reach places, so you may have to consider removing a livewell tub, cooler, or access panel to get to the tank. Loosen the tank from its bracket and locate the oil supply hose that comes from the pump on the tank and heads toward the engine. You should notice a small, white, inline filter that strains the Yamaha 20W-40 4-stroke outboard oil in route to the engine. This small filter is often overlooked, but without a steady supply of Yamalube 20W-40 4-stroke outboard motor oil, your engine will quickly go into reduction mode, or worse. Cut the small zip ties that secure the oil line to the strainer and replace the strainer quickly before you drain oil all over the bilge. This process is a little messy, so a few petroleum sorbent pads can help avoid a mess. Having some good quality nitrile gloves on board the boat or around for your service is also a great idea.

With the tank loosened from its bracket, use a small service flashlight to illuminate the bottom corners of the tank. The clear plastic will allow you to spot any debris or water deposits accumulated inside the tank. If found, you will need to remove the tank, drain it, and clean it. Debris is most often introduced from fill caps being left open, damaged fill cap o-rings, or dirty containers used to purchase bulk oil.

When complete, reinstall the tank into the bracket and remove the cowling from your engine. Use the manual transfer switch on the side of the engine to verify oil is flowing through your new filter and the system is primed. Your Yamaha 4-stroke oil maintenance is now complete. You are ready to begin your engine service.

Can I use automotive engine oil in my Yamaha outboard engine? 

while many boat owners wonder about this, the short answer is that Yamaha outboard motors are vastly different from your automotive engine, so you’ll want to avoid using regular automotive engine oils. Use Yamalube 20W-40 4-stroke outboard motor, which is specifically formulated for the rigors of the marine environment, like all Yamalube 4M engine oil for four-stroke outboards, and Yamalube 2M engine oil for two-stroke outboards.

How is Yamalube 20W-40 marine motor oil different?

Yamaha has spent countless hours and resources to ensure that only the best Yamalube 20W-40 marine motor oil, specifically suited for the marine environment, goes into your Yamaha outboard engine. PartsVu.com can confirm that this oil was formulated to withstand the harshest marine environments and most strenuous Yamaha outboard operations. Whether it’s extended full-throttle operation, engine-punishing “out of the hole” acceleration, or hours of trolling, genuine Yamalube engine marine motor oils can handle the job at hand.

Additionally, Yamalube oil delivers superior lubrication and anti-rust protection for outboard engines in marine environments and works to guard against ring stick, carbon buildup, and varnish. Yamalube 4-stroke engine oils have the best anti-foaming formula available, and unlike passenger car oils, they are certified by the National Marine Manufacturers Association.

Aren’t all outboard oil filters the same?

While most outboard marine oil filters look the same, it’s what’s on the inside that counts most. Yamaha marine outboard oil filters are manufactured specifically to protect Yamaha outboard engines, using only the finest components and construction methods available. This includes special filter media and metal filter media bases (instead of cardboard), to help them achieve a level of durability and filtration far superior to most “off-the-shelf” oil filters. From the quality of the materials used to their high-quality construction, Yamaha outboard marine oil filters simply outperform and out-protect aftermarket alternatives.

How do I remove old oil from my Yamaha outboard?

You can extract spent engine oil from your Yamaha outboard engine by removing the oil pan drain screw plug. The extraction method requires the use of a vacuum extractor which is inserted down the dipstick tube and uses suction to pull the spent oil from the pan. 

For inline Yamaha four-stroke outboard models (F15 to F150), the Seawell drain kit can be used to minimize the mess. On larger V6 models, to access the drain screw, remove the plastic chaps that cover the midsection of the engine. Be sure to have plenty of drain pan capacity as some of these engines can hold up to seven quarts of oil. We also recommend a petroleum sorbent pad to catch any errant drips and keep your driveway or lawn clean.

How do I install a new oil filter and add fresh Yamalube 20W-40 marine motor oil?

Once you have inspected your spent oil and filter, set them aside for proper disposal. If you removed the drain screw to empty your oil, install a new crush gasket and reinstall the drain plug. The new oil filter should be removed from its package and the o-ring lubricated with a thin coat of fresh engine oil. Spin on the fresh oil filter and gently tighten with your filter wrench to seat the o-ring without over-torquing.

Loosen the yellow oil fill plug on the top of the engine and pour in fresh oil. Allow a few minutes for the oil to properly drain down into the oil pan with the engine trimmed down. Then, add just less than the stated capacity and check the oil level on the dipstick. Filling the oil to the lower level on the dipstick will help you to measure if the oil level changes over time. With your Yamaha 4-stroke outboard motor oil change complete, you are now ready to move on to completing the rest of your 100-hour service.

How do I remove the old oil filter from my Yamaha outboard motor? 

First, drain the spent oil from your Yamaha outboard motor. Then, work on removing the engine oil filter. Depending on your specific Yamaha outboard model, your marine oil filter may have a drain lip that will help keep the mess to a minimum when you unscrew the old filter. But most older engines don’t have this feature. Put down absorbent rags, or place a small cup below the filter prior to removal. Using a properly sized filter wrench or socket, loosen the filter. Yamaha produces a socket for their 5GH sized filters. Some technicians make a practice of puncturing the filter to allow trapped oil to drain back into the block prior to removal, but this will ruin your ability to take the filter apart later for further inspection should you wish.

How do I flush my Yamaha 4-stroke outboard engine?

After performing a standard outboard precheck, connect a hose to your Yamaha 4-stroke outboard motor and move to the helm. Be sure that your flush attachments fit your lower unit appropriately, and remove the lower unit intake screens for the best water pickup. Note that Yamaha SHO engines and lower units with low water pickups in some horsepowers require additional flush block-offs to make sure they don’t suck air. In the absence of the OEM block off, duct tape works too.

If you have not previously run your Yamaha 4-stroke outboard engine on a flush attachment, consult your owner’s manuals for specific instructions. From the helm, lower the engine into a normal running position. Verify the garden hose water is fully flowing and the area around the boat and propeller are clear. With the control in neutral and, the key lanyard hooked up, turn the key to the “run” position. Check your gauges and observe the voltage reading. Ideally, the reading should be in the 12.6-13.2V range. If lower, charge your starting battery and further investigate. Start the engine and allow it to idle – listening for any abnormal noise or vibration. Verify that the gauges are all working properly, and the engine is charging the on-board battery between 13.6-14.3V. Check for adequate water flow coming from the exhaust and tell-tale stream of your engine. If the engine runs properly on the hose, turn it off and visually re-inspect the engine for leaks after allowing it to sit for a few minutes. Reinstall the cowling, remove the flush (and tape) and you’re done!