I’ve googled the I-net and searched this site and can’t the answer. I’m sure you guys can help!
I don’t have any manuals for my generator (Kohler model 10e). I’m looking for the recommended oil as it’s time to change oil, fuel, impeller, etc etc. I ordered a tuneup kit from eBay that’s got plugs, impeller, anode, belt, and filters. But I can’t find any info on oil.
What’s the recommended oil for my gas generator?
Kohler gas genny model 10e oil specs
- Mikwallace
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Kohler gas genny model 10e oil specs
1959 Larson 16’
1979 Caravelle 18’
1998 Chaparral 2330 7.4 L Mercruiser
2003 Chaparral 260 Ssi 8.1 L VolvoPenta DuoProp
1998 Carver 405 AC 7.4 Horizons


1979 Caravelle 18’
1998 Chaparral 2330 7.4 L Mercruiser
2003 Chaparral 260 Ssi 8.1 L VolvoPenta DuoProp
1998 Carver 405 AC 7.4 Horizons
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Re: Kohler gas genny model 10e oil specs
I have always used 15w 40 in my previous gas generators as well as the engines however we store the boat in winter therefor 15w40 works well as it is more of a summer oil. Point is the oil you choose needs to be good for the coldest temps you will see. Is the boat winterized or do you run it year round and if so how cold does it get. Same oil you use in your 7.4 horizons will be fine in the genny. 
That being said, our Kohler whole house generator uses 5w 20 year round however our winters can get brutally cold in January and do need the 5w part in this case.
That being said, our Kohler whole house generator uses 5w 20 year round however our winters can get brutally cold in January and do need the 5w part in this case.
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Re: Kohler gas genny model 10e oil specs
Thanks for the input!
I couldn’t find any info online so I called Kohler and they recommended 5w30 or 10w30 full Sun. Although the temps get cold here, my bilge never gets below 40*. I have some 10w30 valvoline Dino oil so think I’ll use that. Maybe next time I’ll go with the 15/40??
Looks like the previous owner used straight 30w in both engines and genny. I’m not a fan of that. Both engines are using oil, so I’m thinking the 15w40 will be better in the engines. The genny doesn’t use any oil.
I couldn’t find any info online so I called Kohler and they recommended 5w30 or 10w30 full Sun. Although the temps get cold here, my bilge never gets below 40*. I have some 10w30 valvoline Dino oil so think I’ll use that. Maybe next time I’ll go with the 15/40??
Looks like the previous owner used straight 30w in both engines and genny. I’m not a fan of that. Both engines are using oil, so I’m thinking the 15w40 will be better in the engines. The genny doesn’t use any oil.
1959 Larson 16’
1979 Caravelle 18’
1998 Chaparral 2330 7.4 L Mercruiser
2003 Chaparral 260 Ssi 8.1 L VolvoPenta DuoProp
1998 Carver 405 AC 7.4 Horizons


1979 Caravelle 18’
1998 Chaparral 2330 7.4 L Mercruiser
2003 Chaparral 260 Ssi 8.1 L VolvoPenta DuoProp
1998 Carver 405 AC 7.4 Horizons
- bud37
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Re: Kohler gas genny model 10e oil specs
I think most of us just use whatever we use in the main engines for ease. Really it is just a small equipment/tractor engine.
Nothing wrong with Sae30 for both but now the multigrades are way better. I used to use Sae 40 in all many years ago, but since moved to rotella 15w40...there are many other choices though.....
Maybe he was using 30 because he was perhaps seeing some oil useage.
Remember once the engine is running the oil really doesn't care what the ambient temp is.
There are as many views on this oil thing as Carters pills, did you ever come across in the searches, threads titled, "my generator blew up because I used brand ( fill in the blank ) oil "?.....
Nothing wrong with Sae30 for both but now the multigrades are way better. I used to use Sae 40 in all many years ago, but since moved to rotella 15w40...there are many other choices though.....
Maybe he was using 30 because he was perhaps seeing some oil useage.
Remember once the engine is running the oil really doesn't care what the ambient temp is.
There are as many views on this oil thing as Carters pills, did you ever come across in the searches, threads titled, "my generator blew up because I used brand ( fill in the blank ) oil "?.....
FWIW.....The above is just my opinion.
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Re: Kohler gas genny model 10e oil specs
Last time I talked to Kohler about this, they had revised their recommendation a couple of years prior to 5W30 for ALL newer and older units. Either synthetic or conventional are acceptable. 10W30 and straight 30 are acceptable alternatives as well.
- g36
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Re: Kohler gas genny model 10e oil specs
For the last 13 years ive used 10w 30 in my Kohler 10 genset
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Re: Kohler gas genny model 10e oil specs
I changed the oil prior to storage and used 10w30. Prior to that I always used Rotella 15W40. Never ever had a problem. It's just that this year I dug more into the manuals and found what Viper mentioned, 10w30.