Merc’s Opti-Max oil has “gelling” issues ?

[VH5150]

I have been reading on various Merc forums that there is a rumored gelling issue with Merc DFI oil? Any truth to this?

[JOE54]

we have seen some yes especially on boats that set for extended periods of time

[VH5150]

That's not good! Coming off a Winter lay off. I used DFI last season. Went back to Prem Plus, DFI is just way to much $$$. Any issues with Prem Plus or even switching to Pennzoil?

[EuropeanAM]

That's not good! Coming off a Winter lay off. I used DFI last season. Went back to Prem Plus, DFI is just way to much $$$. Any issues with Prem Plus or even switching to Pennzoil?

They're "suitable" oils, but tend to reduce Direct Injector lifespan.

[Tarponstalker]

Yes. I just had my tank cleaned out due to gelled oil. I think it's coming from tanks that way. It certainly doesn't sit in my boat long. I go through 5-6 gallons a year.
I think with fewer people using Optis these days the bulk oil is sitting longer. Just a thought.
I can't believe they charge $65-$70 per gallon here for Opti/dfi oil
I started using a funnel with a screen when filling my oil tank.

[FrancoCialone]

This is another reason I don't buy DFI oil in bulk even though its cheaper, the BPS in Vaughan sells it by the gallon and bulk, don't use that much so will buy it by the gal. when I need it.

[mikeky]

So is it additives that are gelling? If so, and you filter them out, then?????

[EuropeanAM]

Couldn't give a blanket answer to your question, Mikeky. The two I've seen, it's WATER/MOISTURE.

[namakan32]

2005 225 DFI. Ser# 1B149359. 516 hours. For the last dozen years I’ve only put about 25 hours a season on my motor. And last September 2023 I had the low oil horn go off and was confused because the 3 gallon remote tank of Merc DFI was 3/4 full. I found out my oil tank pick up screen was plugged up with gooey oil. So because I was out on a remote lake far from civilization I just cleaned the goo off and primed the engine tank and went on and put maybe 5 more hours on before winter storage. So this spring during first outing same thing, so I dumped the oil out of the tank and unscrewed the pick up tube from hose cap and cleaned them and filled tank with fresh dfi oil. Because my boat is stored in freezing temperatures I’m wondering if I should keep the remote tank almost full in the winter to cut down on moisture in the oil tank just like the gas tank.

[EuropeanAM]

2005 225 DFI. Ser# 1B149359. 516 hours. For the last dozen years I’ve only put about 25 hours a season on my motor. And last September 2023 I had the low oil horn go off and was confused because the 3 gallon remote tank of Merc DFI was 3/4 full. I found out my oil tank pick up screen was plugged up with gooey oil. So because I was out on a remote lake far from civilization I just cleaned the goo off and primed the engine tank and went on and put maybe 5 more hours on before winter storage. So this spring during first outing same thing, so I dumped the oil out of the tank and unscrewed the pick up tube from hose cap and cleaned them and filled tank with fresh dfi oil. Because my boat is stored in freezing temperatures I’m wondering if I should keep the remote tank almost full in the winter to cut down on moisture in the oil tank just like the gas tank.

Just a note- we ask that separate engines be in their own separate post/thread so as to avoid confusion and/or post hi-jacking. Given the topic matter- We will leave it THIS time (only).

There should be only an extremely small amount of access to atmospheric moisture unless you have leaks in the system somewhere. And you would normally not want your tank level above 80% volume (anyway). Thus, I'd recommend something in the normal level range (35 - 80%).