Added Mercury Optimax /DFI 2-Cycle Outboard Oil to remote tank- now smoking at idle

Nitro Owners Forum

Help Support Nitro Owners Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Pimpsy

NTO Supporter
Supporting Member
Joined
Aug 27, 2024
Messages
20
Reaction score
4
Location
NJ
Noticed that some other oil was being used in my new (to me) 2013 Nitro Z-7 with Optimax 150. Decided to purchase the recommended Mercury oil and added the full gallon to the existing oil. This left the tank about 80%-ish full.
Now, after running at all, when I drop to idle, it blows a fair amount of smoke. I drained the oil down to about halfway and the condition might be slightly better, but still smoking at idle.
Now I see a sticky online somewhere about NEVER MIX MECURY OIL IN THE REMOTE TANK. Ugh.
Can anyone offer any advice?
TYIA,
Pimpsy
 
Noticed that some other oil was being used in my new (to me) 2013 Nitro Z-7 with Optimax 150. Decided to purchase the recommended Mercury oil and added the full gallon to the existing oil. This left the tank about 80%-ish full.
Now, after running at all, when I drop to idle, it blows a fair amount of smoke. I drained the oil down to about halfway and the condition might be slightly better, but still smoking at idle.
Now I see a sticky online somewhere about NEVER MIX MECURY OIL IN THE REMOTE TANK. Ugh.
Can anyone offer any advice?
TYIA,
Pimpsy

First off do not mix different oils. If the oil was a blue color then it mite have been Mercury's premium plus. That oil is for non DFI motors even though it will work. Opti-Max DFI oil is brown and a lot thinner. You should start from scratch, drain your main tank and the aux tank on the motor. Then with just one gallon of Opti oil fill aux tank and the rest in the main tank. Both oils are full synthetic and do not smoke as much as regular 2 stroke oil. You have to have a starting point so you can go by the process of elimination to diagnose the problem.
 
Thanks for your reply, Jerry. The oil was not brown, I think it was sort of greenish blue, but it was definitely the recommended oil:
Mercury Optimax /DFI 2-Cycle Outboard Oil 1 Gallon 92-858037K01
I started getting four beeps every couple of minutes and I'm waiting on the engine mounted oil sensor to be replaced. Not at all sure how this explains the white smoke; my feeling is that something is going on that the mechanic hasn't put his finger on yet, but we'll see.
In the meantime, I bought VesselView and I'm waiting for that to come in so I can see some data for myself.
 
Thanks for your reply, Jerry. The oil was not brown, I think it was sort of greenish blue, but it was definitely the recommended oil:
Mercury Optimax /DFI 2-Cycle Outboard Oil 1 Gallon 92-858037K01
I started getting four beeps every couple of minutes and I'm waiting on the engine mounted oil sensor to be replaced. Not at all sure how this explains the white smoke; my feeling is that something is going on that the mechanic hasn't put his finger on yet, but we'll see.
In the meantime, I bought VesselView and I'm waiting for that to come in so I can see some data for myself.

Sounds like you have it under control, however I think the sensor is not the problem but the float in the tank. They get saccharate with oil and don't float any more. The only way to fix it is to buy a oil tank. As far as the white smoke, does it smoke all the time while at idle?
 
Don't forget to ensure the impeller is not more than a year old. The four beeps could also indicate overheating due to worn out impeller. The white smoke could be steam vapor as well. Just sayin, don't get locked into only one school of thought.
 
I have a 2016 200hp Optimax and I have the vesselview. Couple of things...

I regularly get the 4 beeps at idle. I have checked it on the vesselview and it is (on mine anyway) a low temp warning. I ran it on with vesselview turned on and could watch the temperature. The thermostats (there are 2 thermostats on mine) are set to open at 130 but 130 is where you get the low temp warning. Temperature would rise to about 135, thermostats would open, temperature would drop to 125 and I would get the warning beeps. It would keep going like this but once running, no more beeps.

On mine, there is no float in the on-engine oil tank. There is a sensor that will beep with low oil and eventually put the motor into guardian mode. This happened to me and the issue was the strainer in the remote tank was plugged. Just pull it, wash it in carb cleaner and replace. I googled it at the time and and talked to Mercury but there was nothing on the strainer plugging. However, if you google it today there are quite a few posts with the suggestion that the Optimax oil is sitting on shelves longer because newer motors are 4-stroke.

I have only used Optimax oil in the black 1 gal bottle since new & for what it is worth, my optimax oil is and always has been brown.

And if you do mess with the oil system, make sure you bleed it properly and re-set the motor to "break-in" mode.
From Bass Boat Central:
How to BLEED the ENGINE MOUNTED OIL TANK
1. Ensure that the BOAT tank has adequate oil in it (1/3 or higher level).
2. Verify all caps on the BOAT tank are TIGHT, and o-rings are in place under the caps.
3. Remove engine cowling, and set engine trim to "level-trim".
4. If you've OPENED any part of the oil system, or suspect air may be trapped in the lines, utilize a Turkey Baster or Syringe to "suck" some oil out of the ENGINE mounted tank (usually want the level down about 3/4" to 1" FROM THE TOP OF TANK for best results).
5. With cooling water supplied to engine, start engine and allow it to idle.
6. Loosen the cap on the ENGINE MOUNTED oil tank (approximately 1-1/2 turns). Allow the engine to continue idling, and watch carefully for the oil level to rise. This is a "pressure fed" system, so oil is being "pushed in" as air is being "released" through the cap. This may take only seconds, or as long as a couple minutes.
7. As soon as oil begins to "spew" from the cap, snug it down (don't overtighten- it will break/crack).
8. Wipe up all spillage.
9. IF you have repeat occurrences of this problem, you will need to have the system checked for air leaks, faulty check valves, etc. (Same would be the case if the system does not bleed as above described).
From Mercury:
Priming Optimax Oil Injection Pump: (Required after replacing Oil Inlet Hose Filter)
  • Connect water to the motor (for running it).
  • Make sure remote oil tank is filled & caps are on tight
  • Loosen the vent cap on engine mounted oil reservoir (don’t remove it – just loosen it)
  • Fill the engine fuel system with fuel. Connect the fuel hose and squeeze primer bulb until it feels firm.
  • Make sure “kill switch” is on (motor will run)
  • Turn ignition key switch to “ON”.
  • Within 10 secs move remote control handle from neutral into forward gear 3 to 5 times.
  • This starts priming process which may take a few minutes (you will hear the oil pump ticking)
  • Start and run the engine till oil overflows the engine mounted reservoir tank
  • Turn off engine and tighten the engine mounted oil reservoir cap.
  • It also resets the engine break-in period (more oil for 2 hrs of running)
Hope this helps...
 
Thank you for the very detailed and thoughtful replies.
I also don’t understand why the mechanic would suggest changing the sensor in the engine mounted tank when it seems more logical to suspect the float in the remote tank?
This also does not explain the copious amounts of white smoke or vapor that come out of the engine at idle after any sort of use.
The mechanic comes highly recommended but admittedly I am dubious.
In younger years I was a Harley Davidson mechanic and have a fairly in-depth understanding of engines in general but not two strokes or impeller systems.
I’m hopeful that mechanic will sort out whatever is going on but in the meantime I bought vesselview and I’m going to start pulling diagrams in case I need to start doing a deep dive into this myself.
Thanks again for taking the time to make these very detailed and helpful posts. If you have any Harley questions, I can probably help. :)
I will update here with anything I find out.
 
For what it is worth, my remote tank does not have a float (or any sensor) in the remote tank. The only low-oil sensor is in the engine mounted tank.

And I agree that the smoke at idle is concerning. My Opti does not smoke at all. Maybe it is steam but the vesselview should be able to tell you that because you can monitor coolant temp in real time.

I too am pretty handy with a wrench but those DFI systems are somewhat complicated. After my issue with the remote tank intake screen plugging, someone who I thought would have known better, told me I should forget about the whole oiling system and just put 2-stroke oil in the main gas tank. Well, that would have wrecked the motor since the oil injection system in addition to oiling the cylinders, also oils the air compressor.

Good luck! Hope you figure it out.
 
Mechanic and foreman explained today that the sensor is on order, and that they both believe the white smoke at idle is steam and is normal.
We are not talking about a small amount of steam ok...it's billowing out at idle, but they say not to worry about it.
I will install Vesselview on Thursday and take the boat out as they have explained that they think it's good to go despite the beeps.
Can anyone offer adivce as to what I should look for in Vesselview? Not sure what the norms are although hoping the app will let me know.
TYIA
...to be continued...
 
Mechanic and foreman explained today that the sensor is on order, and that they both believe the white smoke at idle is steam and is normal.
We are not talking about a small amount of steam ok...it's billowing out at idle, but they say not to worry about it.
I will install Vesselview on Thursday and take the boat out as they have explained that they think it's good to go despite the beeps.
Can anyone offer adivce as to what I should look for in Vesselview? Not sure what the norms are although hoping the app will let me know.
TYIA
...to be continued...

You should tell your tech advisor that you want a leak down test done on the motor. Because I think the "smoke" is in fact water that the motor is ingesting and turning it into steam. Did they do compression test? If not they can do one then. I am sorry but I don't believe that the sensor in the engine mounted tank is bad. 90% of the time it's the float in the tank. The sensor is a fixed mount in the tank and the float rides up and down on the sensor like a magnet. The float completes the connection. Once the float drops past the sensor you loose the connection and then the alarm goes off via ECU or PCM " propulsion control module" . I know Meerkat said that the thermostats are 130' however they are 143' for the 2.5ltr. "150" motor and the alarm will go off at 186'. So when you get the vessel view you will be able to monitor the open and closing if the t-stats.
The only other thing did you check the fuel water separator filter for water, it has a sensor on the bottom of the filter that senses for water in the fuel and will get the same 4 beeps every 4 min. Just my 2 cents
 
Thanks so much guys! All very solid advice and tips.
Everyone here is slammed with winterizations but I’m trying to find someone to come in to get a second opinion and also perform a leak down in compression test.
Stay tuned!
 
I was curious about the references to a float in the reserve tank because mine does not have one. So I looked it up on Bass Boat Central and apparently it is an option that connects to a dash mounted oil guage for reserve tank level. It does not connect to the computer on the motor and will not give any of the Mercury warning beeps. The on engine oil tank has the low oil sensor that will give the the warning beeps and actually shut the motor down into guardian mode (idle speed only) if the motor becomes starved of oil. The part about guardian mode I know from personal experience on Lake Erie, 20 miles from the ramp. Remote tank strainer was blocked so the on engine tank was not getting fed...
 
I was able to successfully install the VesselView today. Very cool!
It showed the alert for low oil in the engine mounted tank.
However, it also showed zero oil pressure and the oil temperature of 32°F. Seems obvious that something is wrong with that sensor and I am still waiting for it to be replaced.
I’m hopeful that once the sensor is replaced, things may settle down.
Also waiting to connect with the second mechanic for a leak down and compression test and look at this and that just to see what’s what and verify that everything is fine.
Other than the beeping the motor seems to run well. A little steam at idle but I wasn’t able to really run the motor so not sure, will figure that piece out when I can.
 
Back
Top