What's the proper oil for a push mower

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I'm just curious what's the actual oil spec you're supposed to use in a typical push mower engine. I always thought PCMO wasn't that great for mowers because it holds all the dirt in suspension where a filter would normally clean it out but with no filters on a typical push mower engine, what's the actual proper oil to use?
 
To add to the above statement:

"When choosing lawn mower oil, use a high-quality detergent oil classified as "For Service SF, SG, SH, SJ" or higher. Do not use special additives".

So Briggs does recommend a detergent oil as noted in this statement on their web page.
 
Originally Posted by jayjr1105
I'm just curious what's the actual oil spec you're supposed to use in a typical push mower engine. I always thought PCMO wasn't that great for mowers because it holds all the dirt in suspension where a filter would normally clean it out but with no filters on a typical push mower engine, what's the actual proper oil to use?

What does the manufacturer of your engine recommend? Have you ever seen a recommendation for a non-detergent oil, ever? It's not a secret nor should it be confusing.

I always wonder where people get these notions when the manuals don't say anything of the sort.
 
Honda
[Linked Image]


With a special "Notice": Using nondetergent oil can shorten the engine's service life, and using 2-stroke oil can damage the engine.
 
I run 10w30 high mileage oil in my push and riding mower. Very little oil usage and easy to find oil as well.
 
Any thing leftover from you car**: keeping gas clean and blade sharp and balanced is more important. Add to that Cleaning and oiling the air filter.

**But NO 20 grade or 50 grade but anything in between is fine.

Go to for ODPE was 10W30 Rotella Triple Protect dino.

I think you can only get this in bulk now, not in gallon jugs.

All my equipment HATED T5 10w30 semi synth. - Or at least what they blended 3 years ago.

Your engine will outlast the rest of the mower. My 3.5hp briggs Yard Machines was purchased in 1991 and is still going strong except wheels, and bags are falling apart. That got an OC maybe every 3 years or so.
 
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I run Amsoil 10W30 small engine oil. I order a few quarts with the other lubricants.

The only special needs for a lawn mower might be high temp. Its typically run in the summer, the engine is air cooled via its cooling fins that may be covered in grass.
 
Most owner's manuals recommend SAE 30 or synthetic 5w30. Honda is the only one that I've seen 10w30 marked right near the dipstick on their lawnmower engines.

With that said, mowers will run on basically anything that resembles oil. After working on small engines for close to 15 years I've noticed that keeping the oil level full on splash lubricated engines is more important than the viscosity used. Over the years I've run everything from 0w30 synthetic (snowblower) to 20w50 (old mower that burned enough oil to kill mosquitoes). The modern PCMOs of today are worlds ahead technology wise than those of even 5-10 years ago just so they can hold up to turbo GDI cars. They will be completely fine in a small air-cooled engine. If you want to run the most expensive synthetic PCMO money can buy, go ahead, the engine will be fine, and it will also be just fine on the cheapest gas station name brand oil as well. It's really up to the consumer to use what makes them feel good. My experience has shown it doesn't really matter as long as the oil level is correct. I still have customers who insist on using SAE 30 non-detergent oil, and their mowers are fine.
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I use a M1 EP 0w-20, because I have about 20 oz (mower capacity) remaining in the 5Q jug after I do an oil change for my Honda. I change it every few years since it gets only around 10-15 hrs/yr use.
 
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My 1997 mower calls for straight 30 wy oil. But over the years it's had alot of different brand and weights in it. And it runs the same. By looking at what eveyone else uses, from used oil from their cars, to special "mower use only", to specific API grades, it's obvious you can use any oil you like and whats handy, and the mower motor will outlast the rest of the mower. The biggest danger would be hitting that hidden rock or tree stump and bending the shaft. Then all that special mower use only oil won't mean much to you, as your rolling it out to the curb on trash day.,,,,
 
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Originally Posted by BigCahuna
My 1997 mower calls for straight 30 wy oil. But over the years it's had alot of different brand and weights in it. And it runs the same. By looking at what eveyone else uses, from used oil from their cars, to special "mower use only", to specific API grades, it's obvious you can use any oil you like and whats handy, and the mower motor will outlast the rest of the mower. The biggest danger would be hitting that hidden rock or tree stump and bending the shaft. Then all that special mower use only oil won't mean much to you, as your rolling it out to the curb on trash day.,,,,



This.

The most common killer of mowers from what I've seen are:

1. low oil (usually no oil)
2. Mice nests (see #1)
3. stumps/rocks bending crank shafts
4. wheels rusting off the deck

The most common situation is the mower sits outside or in a shed over winter, mice build nests in the cooling shroud, and the mower overheats which burns up all the oil in the crankcase after a couple uses. This process is sped up by a engine that is either already low on oil, or an engine that already burns oil.
 
Back in the early 80's in high school shop class on small engines we were told to use a 30w high detergent oil since push mowers didn't have filters.
 
Toro mounted Briggs and Stratton engines have vacillated. My father's old beater mower he bought in the mid 1990's preferred 10W-30 but said you could use SAE30. But his Toro 22" Recycler from around 2010 only says detergent SAE30 SF-or newer. I did use 10W-40 in it and noticed it did burn some, but nothing major. I picked up some VWB SAE30 on clearance at TSC for it. I preferred using multi-weight oiis like 10W-30 just for ease of starting in colder months in spring and fall. But modern GII-III SAE30's seem to flow as well as older 10W-30s with a pour point at -27C.....
 
For 12 years of so now all I have used is my left over top off oil and its running just fine. I change it in the early spring and about the first of August.
 
Originally Posted by kschachn

What does the manufacturer of your engine recommend? Have you ever seen a recommendation for a non-detergent oil, ever? It's not a secret nor should it be confusing.

I always wonder where people get these notions when the manuals don't say anything of the sort.


I had an old 2 cycle that called for non-detergent.

My guess is ancient machinery might spec it for lack of anything better existing at that time
 
I use Frankenoil, combination of 5W-20, 5W-30 dino and synthetic.
Mower doesn't know the difference, change it annually - run time is about 25 hours a year.
7HP Craftsman self propelled walk behind from the late 90s.
 
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