Mercury 2-Stroke Oils

[sec56]

I had a Mercury Optimax rebuilt back in 2019-2020 during covid. The Mercury dealer that rebuilt the engine had told me that Quicksilver Premium Plus synthetic was good for that engine. Later, I found out that the Optimax requires DFI oil, so I began running Mercury DFI synthetic blend oil. The engine runs great. Little to no smoke, idles great, and performs well. It performed well on the Quicksilver Plus synthetic blend oil too. But since I've switched to the DFI oil, I have some of the other oil in sealed jugs left over. My question is, can I mix these two oils together to use up the Premium Plus synthetic blend oil without causing harm to my Optimax? I do realize that mixing generally is thought to not be a good idea.
One other question regarding the Optimax DFI oil, SHOULD THERE NOT BE ANY SEPARATION within an unopen gallon of Mercury's DFI oil. I opened a gallon today and began pouring the oil into my oil tank. The I thought than there was something in the fresh gallon of oil when I was pouring it into the funnel. I stopped, changed to a funnel with a screen in it, which captures some amber colored globules which were soft. I shook the balance of the oil that was left in the jug, then poured some more into the funnel with the screen. Globules appear to be gone and have mixed/dissolved back into the remaining oil. The DFI oil has been sitting on my shelf probably around 2 years since I bought it. The jug was sealed when I opened it so I doubt anything was added to it since purchase. So, can I mix these two oils? And should I scrap the oil that is separated or just make sure I shake it up well? I'd like to hear some thoughts on these two things. Thank you ahead of time.

 

[sec56]

I found a post that answers a good part of my questions about those globule or gelling. https://www.bbcboards.net/showthread.php?t=23389. In this post it talks about gelling and compatibility between Mercury' Premium Plus and Mercury's DFI oils. If there is anything someone thinks I should know, please tell me. Have a great day.

 

[cyclops222]

No one has run the MIXING TESTS that you want to do. Do not do it

 

[sec56]

Are there any additives to prevent gelling or retard it. During winter months refineries add anti gelling compounds to diesel fuel. I've never heard of any such thing for 2 stroke oil, but I am curious.

 

[airshot]

I have used Pennzoil tcw3 oil for over 50 years, some jugs have been on my shelf for a couple years and never have I saw any globs or jelling. Last year started using Quicksilver synthetic blend with no issues even mixing these two together. In your case, I would NOT use any oil with issues lol or you describe.

 

[jimmbo]

Being that that your engine is DI Engine, I would stick to the DI Oil, even though Quicksilver Premium Plus is a very good Oil. DI engine throw a whole bunch of Curves as to what is required by the Oil. If you look at the DFI Oil Label, you may or may not find a TCW-3 Cert on it. I know it isn't designed to be used as Premix, likely having additives that don't mix well with Gasoline. It is an Oil developed for the DI Engines

 

[Chris1956]

You should check your owners manual, but if memory serves, Optimax can use regular TCW-3 oil, in addition to DFI oil.

Oil should never separate or get clumps. Dump that stuff.

 

[jimmbo]

When the Optimax and FICHT came out TCW-3 was all there was. The Engine Makers Oils Exceeded the TCW-3 spec, but it turned out even they weren't up to the Task for the DI Engines

 

[sec56]

New question. I've had both Evinrude's and Johnsons. My last one was a 1999 175hp Evinrude Ficht. which was on the boat I bought back in the early 2010's area. I was very hesitant to by this boat at the time due to the bad pr about that engine. After one answer on a forum about this, it was stated "that if it was still running today, then it was one of the better ones." We bought the boat and never had a problem with the FICHT engine until late 2018 when it just flat out quit. Three different dealers couldn't tell what was going on exactly because they didn't have the software for that serial number on my outboard. So, since the engine was nearing 20yrs old, I decided to get a different outboard. Up steps the 4 stoke era for outboards. At the time there was at least a 1 year (plus in some cases) to get a new 200hp outboard. I didn't want to wait a year to get a new outboard. So I shopped around and found the 200hp Optimax which I have now. Everything has been fine up until about a week and a half ago when I began adding Optimax DFI oil the main tank and noticed the gelling. So since then I've been trying to find more information regarding different brand of 2 stoke oils. I run XD-100 in my 15hp H.O. kicker and have not noticed any gelling at all while filling it's tank. When I first started with the Optimax, I was using Premium Plus (TC-W3 rated), then found out that I should be using Optimax DFI oil (not TC-W# rated, but higher), so I did. I was fine with that until I discovered these amber globules (which I'm told is gelling) while adding oil to my main tank. This raise the concern that this could starve my engine from getting the oil it needed to run without damage. My search has me leaning towards XD-50 which rated as a better 2-stoke oil the Premium Plus, but still not as good as Optimax DFI. I've used XD-50 both as a premix and as adding it to a oil tank. I've never seen it gel ever, even in our cold weather here in Michigan. Add storage duration was never an issue either. For Optimax DFI oil, I've found numerous complaints about the oil gelling. An article suggested not storing Optimax DFI oil very long and to store it in a warm ambient environment. I buy oil in quantities larger than what I usually need for the season. I've saw articles where some Opti owners have used XD-50 in there Optimax outboards with sucess. What I'd like is to hear from outboard mechanics about their experiences with owners who have used other TC-W3 oils in their Optimaxes. If some one out can give me a url where Premium Plus, Optimax DFI, XD-50, and XD-100 have been tested and compared to equavalent oils, that would be great.

 

[Chris1956]

I would recommend that you don't use any non-Merc TCW-III oil. They may be OK, but why mess around. You might check to see if the OMC DI oil is compatible with Optimax. I would expect it will.

If it were me, I would ask the dealer that sold you the oil with the clumps.