Is older oil ok to use

[harrisg]

I just bought a new 6 hp nisson 4 stroke engine and they say to use a 10/40 oil. I have a lot of 10/40 pennzoil that is about 6 years old and never opened. I am assuming that unused oil does not have a shelf life but I thought I'd ask the experts to see if I'm right. So is it ok to use?

 

[north40]

Re: Is older oil ok to use

Should not be a problem. Sometimes 2 stroke oil will gel after 3-4 years but normally 4 stroke oils will have a very long shelf life. Pour some in a clear container and if there is any gelling or separation, it will be evident.

 

[LubeDude]

Re: Is older oil ok to use

My take on it is that even if the oil was new, I wouldnt use a 10W-40 in an outboard, the viscosity improvers in a 10W-40 will shear away, breakdown, whatever to quickly. Some auto manufactures even state that it will void your warrenty if you use it. I dont like it.

 

[mallardjusted]

Re: Is older oil ok to use

LubeDude,<br /><br />The specs on this engine (actually all their 4-strokes 4 to 30 hp) say SAE 10-30 or 10-40. My Yamaha F50 also has the same requirement. Are you saying you prefer 10-30 over 10-40, or ???

 

[LubeDude]

Re: Is older oil ok to use

Id use the 15W-40 Pennzoil Marine, or the 25W-40 Merc oil. Wouldnt be anything wrong in using the 10W-30 . What year boat are we talking about. Its only been in the last 5-6 years that the 10W-40 has been known to get bad reports. Maybe longer.

 

[mallardjusted]

Re: Is older oil ok to use

OK, I was just trying to understand what your options were to it. My motor is new, and currently has the appropriate 10-30 in it. Once I get it broken it, I will switch to Mobil-1 10-30, as I use my motor where temperatures can sometimes get down to zero. I've learned through experience (2000 Yamaha f40)that dino oils of 10-30 or 10-40 do not flow at all at such low temperatures.

 

[TheOilDoc]

Re: Is older oil ok to use

I would recommend you use the 10W-30 or 10W-40 viscosity along with the appropriate classification of oil that your manufacturer recommends for the new outboard.<br /><br />6-year old oil probably won't meet the manufacturer's latest API classification requirements. And if the oil was an automotive oil that contained insoluble additives, they may have settled out.<br /><br />That outboard doesn't require much oil. I suggest you spend a couple bucks on a quart of new stuff that meets the spec. No warranty concerns that way.

 

[ED21]

Re: Is older oil ok to use

I found a pint of Sears Gamefisher 2 stroke oil from the late '70's sitting on the back of a shelf. It's rated TCW, but I think I'll just let it sit there. <br />Maybe I can sell it on Ebay or take it to the Antique Roadshow someday & see if their are any "oil" or Sears collectors out there.