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  • Writer's pictureDave LeGear

Low budget Outboard Pre-Lube Pump (4 Stroke only)

The reason Military and many other Industrial-grade engines last so much longer (other than being built for such and run expensive lube oils) is that they employ Pre-Lube pumps to circulate lube oil throughout the engine before it is lit off / started. One of our long-standing checklist items back when I was in the USCG, and yes, this was well past the use of Cannon Balls and Sails for those calling me OLD! LOL... I was to bring online and ensure we had X amount of Oil PSI before the crank was spun over a single degree. So, looking to employ such thinking on our past Yamaha F70 Outboard, especially after an engine oil change... I discovered that "if" I left the red kill safety switch insert disconnected (unlike my past BF150 Honda), I could spin the engine over for some time, and it would not start.



Yamaha Outboard start switch

This is great! And though not an actual pre-lube pump by design, it allows one to spin the engine over and allow oil pressure to build up since the oil pump is a mechanical pump that is used before putting fire to any cylinder. As such, anytime I go to start the engine now... I leave the kill switch disconnected and spin her over for 5 to 10 seconds to build up oil pressure inside the Engine before I reach down and insert it for the final "Light Off." Now, will this help any? Well, it's much better than the engine going from setting (sometimes for days or longer) and starting right up with many components dry, now under a full load, and getting hot real fast, than having no oil circulation at all. Also, it is a good practice after making an oil change, and almost all the new oil is just sitting in the oil pan so you can move that fresh oil around the engine. I am sure some will say this could be hard on a Starter. If you stayed on the ignition switch for an extended period, I might agree; therefore, I do it for such a short period. And in the long run, I would much rather swap out a starter than rebuild the top end or entire engine any day! Again, you do not need to spin her over for an extended period... Now, this was tested on my 2013 F70 and my 2022 115 SHO Yamaha, and I "suspect" that is how Yamaha makes all their more recent ignition switches, and it might work the same for you. Easy enough to test for sure... It could work for other makes/years of Outboards, knowing how they all source many of the same parts from the same vendors. My past 2004 Honda would not even turn over if disconnected. Again, it is easy to test if you would like to try this process and, if nothing else, to ensure your safety switch works as designed. I would ensure water is hooked up and flowing through a set of muffs and the prop is clear before trying.


I hope this helps extend your Outboard's life, and let us know your results! 👍


Along these same lines, and to help save on some more wear and tear on your costly engines! You may want to read our product coverage on (quite telling) a very efficient way to help save on those engines and afford a great ROI versus repairs or rebuilding one.


Filter Mag

You can read more about them by clicking Here and follow an article by clicking Here.


So, try one and see how much longer your oil stays cleaner. This is when those sub-20-micron little particles of metal that are now passing through your oil filter media (usually just paper) are getting stopped there. This is not acting like tiny particles of hard metal sand circulating in your expensive engine! I recommend starting your search for one regardless of the application (Marine, Automotive /RV) by first clicking Here.


And do let them know that Flats Nation sent you and that we have a promo code for you to use when ordering! Just use "FlatsNation10" to receive 10% off on your entire order 😊



In the meantime,


We invite you to take in a few Flats Nation Podcast Episodes to help "Scratch that Fishing Itch" when working or traveling and you cannot hitch up the Skiff and go, on these links:


Our main podcast page works well for your mobile devices since it will stream (or download) right on your phone/tablet. It can be found by clicking Here.


Our newer Flats Nation YouTube Channel can be found by clicking Here and sharing them with family and friends if you find them Entertaining and Educational! We have some great guests in the works and planning stages on a wide range of topics and product coverage soon.


Plus, our store has some new clothing and items you can review and order by clicking here.


Tight Lines, and God Bless!

Dave and the Team


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