Generator oil?

Does fuel type affect oil change interval? If I'm running it off natural gas wouldn't it burn much cleaner and not have deposits?
Yes, natural gas and propane burn cleaner, less deposits in the oil. My propane Generac has a programmed 2 yr oil change cycle in it. Oil stays super clean looking at it compared to my old gas gen. sets. Oil that comes out of it looks good enough to use in OPE motors, not that I am that cheap.
 
Natural gas has a sulfur-based oderant added. The oil in my generator stinks when I change it, so I expect the oil to deal properly with the sulfur.
 
But if the manual is saying 50hr OCI that's a basically two days. It doesn't specify based on different fuels. Should I stick to that or not worry about it so much? I stocked up on some QS full-synthetic 10w30 just because it seemed to have the same spec approval as the Pennzoil Platinum and others.
 
I prefer a HDEO 10W-30 in OPE. But, Honda and their Chinese clones really aren’t picky on oil. I have a mix of MaxLife, M1 and PP 5W-30/0W-20 in a Honda GCV160. It was all dregs harvested from “empty” bottles and partial quarts.

Even a basic PCMO changed yearly is going to be better than 99% of what people do with OPE of leaving whatever oil is in there.
 
Rotella T4, buy a 2.5 gal jug as you'll be changing it every few days. Also get some spare spark plugs, your spark gap will need to be smaller on NG than on gasoline.
 
Also get some spare spark plugs, your spark gap will need to be smaller on NG than on gasoline.
Can you expand on this? Does it hold true with LPG as well? Neither of my dual fuel generators say anything about using different spark plug gaps for different fuels.
 
If it is cold (Houston so under 30 degrees) I will run 5w30 full synthetic (same as I use in my truck so I have it on hand)

Over 30 degrees but less than 60 I use 10W30 diesel rated synthetic blend Valvoline Blue.

Over 60 but under 90 I will use HD SAE 30 specific for OPE

Over 90 I will be using 15W40 diesel rated oil.

I have 42 quarts on hand - but if I ran out of something I could swap out one of the other oils without any problem.

Even if below freezing - if I ran out of 10W30 I could put SAE 30 that I have stored inside into an already warm generator and it would run fine.

I also have a jug of 5W40 full synthetic - I figure I can use that anytime in any condition.

I change it every 25 hours - and if used as a back up generator you should take a look on page 24 of your manual where is says

• If it often works under high temperature or high load, oil shall be changed every 25 hours.


I just helped my SIL break in a new generator. We ran it 2 hours and then changed the oil it was dark but I have seem worse.

Then we ran it for 6 more hours.

I have considered getting a similar unit - if I ever do I will never run it on gasoline - well unless it is use gasoline of not run it. It will be a PITA to get all the gas out - and even if you run it until the engine stops it will still have 10 or so ounces of gas left.

That will turn the bottom of your tank to rust.
 
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I've had two 16KW Generac standby generators and have always used the recommended 5w-30 synthetic. Any name brand will do. I stick to annual oil changes, which are usually after about 35 to 40 hours run time.
 
Castrol CRB 15w40 for natural gas generators is avaliable

I have rental generators in Oklahoma summers and winters 15w40 thousands of hours combined
 
Can you expand on this? Does it hold true with LPG as well? Neither of my dual fuel generators say anything about using different spark plug gaps for different fuels.
Not the same for LPG but the dual fuel gens may bake a spark gap into the cake.

If you have a gasoline generator that you put a kit on to let it run on NG, you have to close the spark gap up to 20 thou, if you don't it'll run fine for a day or two but then it won't start on NG but it'll start fine on gasoline. Close the spark gap and it'll run fine on either.
 
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