How much oil should a generator burn?

zoulasNovember 8, 2012

I have a Cummins/Onan 20KW Propane generator. Just purchased new. With hurricane Sandy, the generator ran for 5 days. After 2.5 days, I stopped it and had to add 1/8 quart oil. After the second 2.5 days, the power came back and I had to add another 1/8 quart. At first I was startled at the oil consumption. I called the dealer I bought it from and he said its totally normal. I then called cummins and they also said its completely within spec. Was I too optimistic in thinking it should not be burning any oil? Thanks

Thank you for reporting this comment. Undo

That is such a negligible amount, I'd be quite pleased.
Especially if it was running 24/7 or spent periods under heavy load.

Also, often you'll find some engines are more prone to burn off the "top" few oz. near the FULL mark relatively fast, but the next few oz. take much longer.

In all, you are talking about 8 oz. in 120 hrs. or 1 oz. per 15 hours.
Think how slowly you would have to squeeze an eyedropper to drip 1 oz. in 15 hours.

    Bookmark   November 8, 2012 at 5:23PM
Thank you for reporting this comment. Undo

Yah, And you were on break in too. That engine is doing great, due for an oil change due to hours.

    Bookmark   November 9, 2012 at 6:51PM
Thank you for reporting this comment. Undo

Totally agree. I'm of the old school where if an engine doesn't burn "a little" oil, I'm suspicious-particuarly a diesel.


    Bookmark   November 10, 2012 at 10:13AM
Thank you for reporting this comment. Undo

This is my opinion, other may disagree? that engine might have break-in oil in it? if it does I wouldn't change it too early. Give the oil few hours to alow the engine to seal up. regular oil may induce oil burning if the engine had break-in oil in it. Cam shaft lobs could be damamged if break-in oil changed too early? I would read the owners manual before I would do any servicing?

    Bookmark   November 13, 2012 at 5:49AM
Thank you for reporting this comment. Undo

Break in oil is pretty much a myth in this day & age.

If it's not "broke in" after 5 days, it'll never be broke in!

    Bookmark   November 13, 2012 at 1:48PM
Thank you for reporting this comment. Undo

"Break in oil is pretty much a myth" Not COMPLETELY true, but majority manufactures don't use the oils with extra wear additive.

Honda recommends initial oil change 3000 miles with special break in oil. JD recommends 50 to 100 hours on the initial oil change on their high end equipment. So it's best to read the owners manual for your equipment. I personnel don't like changing the oil too early in any new equipment that's filtered. IF something was left in the oil or crap breaking off then IMO it's issue with that manufacture.

IMO On cheap not filter applications I probably would change the oil after couple hours use due to nothing catching anything suspended in the oil. But thats me Others may disagree?

    Bookmark   November 18, 2012 at 10:33AM
Thank you for reporting this comment. Undo

I agree with RC on this one . Although perhaps not referred to as a Break In Oil by all engine manufacturers these days , most engines are supplied with premium multigrade specific oil quite often semi or full synthetic grade for break in of new engines. I also ensure to run in or extend the hrs of intial oil usage for this purpose on new units which have a source of filtration to pick up any metallic debris.

    Bookmark   November 18, 2012 at 11:14AM
Sign Up to comment
More Discussions
Waterproofing a basement
I get water in my basement just about every spring...
Who Makes This 'New' Craftsman 50cc Chain Saw?
Doing a little research on possible replacement saws......
Old Troybilt Tiller Engine Replacement
I need to replace the eninge on my Troybilt tiller...
Looking for a new "top box" for my tool chest.
My old one died of old, old age and I didn't replace...
Harbor Freight small utility tralier question
I just purchased this harbor freight trailer. I...
Sponsored Products
Balia Rug 7'9" x 9'9" - IVORY
$599.00 | Horchow
Casablanca 2 1/4 in. White Frosted Side Glass for Socket Ring Fitters CSG16
$13.72 | Home Depot
Damara Rug 5' x 8' - IVORY/MAGENTA
$499.00 | Horchow
AF Lighting Naples 8352-4H Mini Chandelier - Blue - 8352-4H
$138.00 | Hayneedle
Prisma Tissue Cover
GG Collection Ogee-G Ceramic Pencil Holder
Classic Hostess
Oil Rubbed Bronze 17-inch Ceiling Mount Shower Arm
Stair Treads: Natco Flooring Sapphire Fleur De Lis Claret 9 in. x 33 in. Stair
$25.97 | Home Depot
© 2015 Houzz Inc. Houzz® The new way to design your home™