SG Oil in SH Mower?

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I have a sealed bottle of SAE 30 lawnmower oil that's been sitting out in my shed for decades. It either came with my B&S 6HP mower or with an older mower of the same brand. The mower manual states "Use a high quality detergent oil classified "For Service SF, SG, SH." The oil bottle states "Meets or exceeds API classification SE, SF and SG/CD." The API website states that SG oil is not suitable for post-1993 engines, but the final service category mentioned in the mower manual, SH, remained in force through 1996. 1. Is "SE,SF,SG" oil ok to use in this "SF,SG,SH" engine. 2. Is the oil damaged from undergoing decades of temperature cycles in the shed? I can easily buy a new quart, of course, but I'd like to understand demands of OPE engines with regard to API service categories.
 
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I don't think aircooled lawnmower engines care at all; as long as they have oil they'll run. Also, I run Sears oil in a can in my parents lawnmower . This stuff --- not my link but same stuff . It's from the 60s as far as I can tell. It's just 10w-30 and their lawnmower is 5 years old. Works no problem! I also ran 25 year old Mobil1 in a vehicle before, no problems. it's still running 115000 miles later
 
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OPE needs oil,preferably automotive style. Main thing is to check level before use. Very few OPE engines die with a full sump. grin2
 

viscous

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Originally Posted by Miller88
Also, I run Sears oil in a can in my parents lawnmower.
Thanks for posting that picture!
Originally Posted by andyd
OPE needs oil,preferably automotive style. Main thing is to check level before use. Very few OPE engines die with a full sump. grin2
Yes, that seems to be the consensus, haha.
Originally Posted by Lubener
Use it for make up oil.
Seems reasonable. You don't subscribe to the "anything works for OPE" philosophy?
 
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Originally Posted by viscous
Originally Posted by Miller88
Also, I run Sears oil in a can in my parents lawnmower.
Thanks for posting that picture!
Originally Posted by andyd
OPE needs oil,preferably automotive style. Main thing is to check level before use. Very few OPE engines die with a full sump. grin2
Yes, that seems to be the consensus, haha.
Originally Posted by Lubener
Use it for make up oil.
Seems reasonable. You don't subscribe to the "anything works for OPE" philosophy?
I do subscribe to "don't waste a single thing" practicers group.
 
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Originally Posted by viscous
I have a sealed bottle of SAE 30 lawnmower oil that's been sitting out in my shed for decades. It either came with my B&S 6HP mower or with an older mower of the same brand. The mower manual states "Use a high quality detergent oil classified "For Service SF, SG, SH." The oil bottle states "Meets or exceeds API classification SE, SF and SG/CD." The API website states that SG oil is not suitable for post-1993 engines, but the final service category mentioned in the mower manual, SH, remained in force through 1996. 1. Is "SE,SF,SG" oil ok to use in this "SF,SG,SH" engine. [/color] Small gas engine manufacturers tend to be behind in their API specification. They are also behind in technology compared to an automotive engine. Since your manual listed API SG as one of the accepted motor oil requirements, then yes, the means you can use your old oil. Because what I said earlier about small gas engine technology, I would consider what you read on the API website irrelevant to your situation. [color:#3366FF] 2. Is the oil damaged from undergoing decades of temperature cycles in the shed? [/color]Don't know without testing, but I guess you will be ok. Motor oil goes through much more temperature fluctuations in use than it did in the shed. Small Gas Engines aren't fussy. Use it up and check your levels.[color:#3366FF] I can easily buy a new quart, of course, but I'd like to understand demands of OPE engines with regard to API service categories.
 
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viscous

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Originally Posted by NH73
Small gas engine manufacturers tend to be behind in their API specification. They are also behind in technology compared to an automotive engine. Since your manual listed API SG as one of the accepted motor oil requirements, then yes, the means you can use your old oil. Because what I said earlier about small gas engine technology, I would consider what you read on the API website irrelevant to your situation. Don't know without testing, but I guess you will be ok. Motor oil goes through much more temperature fluctuations in use than it did in the shed. Small Gas Engines aren't fussy. Use it up and check your levels.
Thanks for your input.
 
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