I recently witnessed a debate on when to change the oil in a lawn mower. To be honest, I’ve never really given it much thought and usually did it in the spring. Apparently this is a subject that people are quite passionate about. The first position I heard was that at the end of the season the oil is contaminated with combustion byproducts that could be quite acidic, and should be removed from the mower before storing it for the winter. The second position was that condensation could occur in the oil over the winter so the oil should be changed at the beginning of the season. I’m sure that it probably makes very little “real world” difference but now I’m curious. I was also scolded for using the Briggs and Stratton Oil Removal Kit to pump out the oil rather than tipping the mower and pouring it out. I was told that I’m leaving sediment behind.
When to change mower oil
- Thread starter PW01
- Start date
- Joined
- Jul 14, 2020
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- 218
according to Briggs and Stratton, never
I change my mower oil annually just before I put it away for the winter
The "IDEAL" way is to change at the end of season, so fresh oil is in the mower while stored and then again before mowing in the spring.
I change it in the spring, some never change it and seem to do well, I think that as long as one uses top-notch oil any system is going to be OK.
I change it in the spring, some never change it and seem to do well, I think that as long as one uses top-notch oil any system is going to be OK.
D
Deleted member 89374
Run a good 0/5W-40 in it and do it once every three years.
Bud_One
Site Donor 2022
I have a 14 year old Cub Cadet 173CC mower - Engine is a Chonda clone - made by Powermore .
I change it every 2-3 yrs and run 10W-30 syn PCMO. I suck it out with a vacuum tank . I've only changed the air filter twice.
Has started every year with no fail . YMMV
I change it every 2-3 yrs and run 10W-30 syn PCMO. I suck it out with a vacuum tank . I've only changed the air filter twice.
Has started every year with no fail . YMMV
In the interest of science and the never needs oil change debate, I decided to catch the break in oil from my newest B&S powered push mower last year just to see how much crud was in it. I changed the oil about mid way through the summer, careful to not let any dirt and trash fall in the container, and then let it sit for a couple months. After the crud had settled I poked a pinhole in the container and set it in a bucket of kitty litter to drain for another couple months. The pic is what was left over after the container drained. Just me but this looks like a lot of debris to have splashing around with the oil for the engine's lifetime. I know Briggs only assumes a 150 hr engine life, but still. Since this stuff will be settling out in the crankcase over the winter I believe in the late fall oil change with whatever 15w40 oil is on sale.
Do they say that in the oversees manual? ;-) lolaccording to Briggs and Stratton, never
I change my mower oil annually just before I put it away for the winter
OMG, i didn't think a BITOG member to go 6 minutes without at least thinking about changing the motor oil... Did you know it had motor oil?Good question. We've had our riding mower for 6 years now and haven't changed the oil or added any in that time.
gathermewool
Site Donor 2023
I change mine every few years. There’s so much additive in RT5/6 that it does not matter
I used to subscribe to the change mower oil every spring habit. But I've seen enough mowers working fine after 5-10+ years without ever having the oil changed (oil black as coal, just periodic top-ups), that I realized I was wasting my money.
It may send shivers up some folks spines, but I go mostly by color these days. When the oil has lost it's amber color and has turned a dirty brown, where it becomes opaque, it's time to go. That equates to about 3 years use for me, somewhere between 50-100 hours I'd estimate.
I always change in spring before mowing season, so if the color is good, I'm skipping a change for that season. Any OPE with oil filters, get them changed @ same interval. Haven't blown up any engines yet. FWIW I use Harvest King 10w-30 All-Fleet (an HDEO) in all my OPE.
I am a stickler about changing break in oil on new units though. I usually do the 1 - 3 - 5 hour change, so three changes by 5 hours, then it's good to go. Probably overkill, but cheap insurance.
It may send shivers up some folks spines, but I go mostly by color these days. When the oil has lost it's amber color and has turned a dirty brown, where it becomes opaque, it's time to go. That equates to about 3 years use for me, somewhere between 50-100 hours I'd estimate.
I always change in spring before mowing season, so if the color is good, I'm skipping a change for that season. Any OPE with oil filters, get them changed @ same interval. Haven't blown up any engines yet. FWIW I use Harvest King 10w-30 All-Fleet (an HDEO) in all my OPE.
I am a stickler about changing break in oil on new units though. I usually do the 1 - 3 - 5 hour change, so three changes by 5 hours, then it's good to go. Probably overkill, but cheap insurance.
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Do what makes you feel good. The mower will fall apart before the engine wears out, nine times out of ten
yee. I do check it every year, its awfully black lmao
Change my oil every couple of years when I replace the blade. Doesn't really make much of a difference. My FIL had an ancient Lawn Boy two stroke. Almost as old as his boat. Ran fine for years, of course never needed an oil change.
- Joined
- May 28, 2014
- Messages
- 2,251
I usually change oil before spring,but will probably drain the oil this fall,then refill with oil in the Spring. Changing it up a bit! 
I changed oil twice in my Toro with B&S engine in past 10 years with ST synthetic 10W30. Changed the spark plug and air filter once this year out of guilt. No oil burning issue and starts up every time.
About same OCI with two snowblowers as well (singe and two stage) , but haven't change spark plugs in those yet in 10 years.
About same OCI with two snowblowers as well (singe and two stage) , but haven't change spark plugs in those yet in 10 years.
