This was a question that we’ve asked ourselves quite a bit. EPNOC grease is what is used in many of our waverunner models, and Evolution being a jet ski rental business, we mainly use the Yamaha VX. At times we’ve seen ourselves rebuilding near 20 jet pumps at once, which requires quite a bit of grease. The issue we’ve ran into is accessibility, EPNOC is not always available, sometimes it’s back ordered, and sometimes we can only get our hands on so many bottles. Our latest rebuild lot put us into this bind again where we were only able to obtain 4 bottles, but had 20 pumps to rebuild, and our other EPNOC order kept getting pushed back by the manufacturer. So we had to do some digging at other options, as we needed to get the skis done and back on the water.
What Is The Purpose Of EPNOC Grease?
EPNOC Grease is the recommended jet pump lubricant for many Yamaha waverunner models. In the jet pump we have 2 ball bearings separated by an inner sleeve that acts as a spacer. EPNOC has multiple functions, it’s function is to stay functional under high heat. As the grease is a part of the drive unit that can spin thousands of rotations per minute, this can create a lot of heat and friction. EPNOC needs to be heat resistant to overcome this high burden from the driveshaft. As well EPNOC has to have some water resistance, even though the jet pump unit has 2 oil seals on the shaft side, and an o-ring on the nose cone, water can still get in the jet pump. EPNOC needs water resistance to keep itself from washing out, as well as to sustain it’s lubricating functionality. Finally it needs anti-corrosion properties, as the pump can build up some moisture, it needs to be able to prevent rust or corrosion from building up on the bearings or inner part of the jet pump housing.
Issues With EPNOC
When it comes to using products created by a manufacturer for another product they make, like lubricants, oil filters etc., they’ve usually gone through great lengths and testing to make sure what they recommend is the best most optimal option. Unfortunately access to the recommended option is not always easy. As well over time, as is the case with EPNOC, we have access to user reviews about product performance. Users have mentioned (from their experience with the product), that EPNOC tends to build up in the nose cone over time, which leads to under lubrication. It has been speculated that this is because EPNOC may be slightly too thick, preventing it from moving as freely to lubricate the bearings.
What Does EPNOC Look Like
EPNOC has the consistency of a thick slime, that is the best way it can be described. It has a dark green color, which definitely gives it the caution of something that should not be consumed. Because of it’s texture it is a little harder to find a product off the shelf that could be used in its place. It is thinner than a normal marine grease (which generally has the consistency of vaseline), and is also thicker than gear oil (which would generally be used in differentials and some other model jet pumps). Do not fret, as the cocktail we have found can still be made with off the shelf items.
So What Do We Use? (Try At Your Own Risk, Still In Testing)
We had a few ideas prior to deciding on this, as we already use gear oil in some of our seadoo jet skis, and we keep plenty of high temp, waterproof grease on hand. But we decided to do some digging prior to our endeavor to see if anyone else had tried an alternative as well that could be easily made at home. What we found was a user on one of the waverunner forums had used a mixture of lucas red and tacky plus synthetic gear oil. This gives you all the properties you need as far as heat protection, water resistance, anti-corrosion etc. This also gives you the control to make it thicker or thinner as you like.
Again, we are not saying this is better than EPNOC, just that it’s easier to find. As well we are still in testing of this mixture, and can’t give long term results as of yet.
How did we start our testing? We have 16 jet pumps we are testing this year, we marked 8 with HM (for Home-Made) on the pump casing, and left the other 8 blank to know which ones had EPNOC. At the end of the season we will break them all down to see how the pumps look, how the grease looks, and the distribution of the mixture. As well if any failures occur during the season we will know if it was either an EPNOC pump or an HM pump. All pumps have fresh bearings and seals all from the same manufacturer, and were all rebuilt at the same time.
Where Do We Start?
For this I will only explain the making of the Home-Made lubricant, as EPNOC is already pre-made. As well we stick to the manual for amounts needed for lubrication (for a 2019 Yamaha VX, the manual states 20g in the spacer, and 20g in the cone, as well as applying marine grease in the bearings during assembly)
For our home-made mixture we used
-Lucas Red & Tacky
-Valvoline 75w-90 Gear Oil
We chose a thinner gear oil, as the purpose was to thin out the Lucas more easily.
First we dumped all of the lucas into a sealable container (make sure it doesn’t take up more than half the container)
Second we slowly add in the gear oil, mixing as we go until it resembles slime. We do not want it to get to thin, so do not add to much. For us we just wanted it to be slightly thinner than EPNOC. If you have EPNOC on hand you should be able to compare the thickness. You do not want it to be runny, or too thin to where it will run out of the cap. You do want it to still be able to slowly move like slime.
After this you should have a decent sized container of usable grease that should last for many many pumps (We did 8, and probably have enough for 100).
You can see below we have pictures of our EPNOC pump we rebuilt, as well as the Home-Made grease pump.
Check back in over time, as we will give any details of the pumps as any issues arise.
Thank You
