Mower oil recommendations

I've ran Kohler 10-30, Mobil 1 Euro 0-40 and RP HPS 5-30 in my mower and generator engines. Can't tell a difference in any of them, all worked fine.
 
About that time to put in fresh oil for the season. I have a zero turn with a Kawasaki FS651V that I currently run KTech 10w-40 until my warranty is up. I inherited an older John Deere GX85 with a B&S. It has sat for many years. I am going to freshen it up to use and was curious what people thought would be a good oil to run. B&S states a synthetic 5w-30 is best (https://www.briggsandstratton.com/en-us/support/faqs/mower-oil-type-and-capacity). I was thinking a 10w-30 synthetic would be better in my area due to the high temps. I run mowers in the spring, summer, and fall. The ambient temp range during those seasons is from 40s to 115 heat index. I was looking at amsoil 4 cycle oil for the John Deere and will possibly put the zero turn on that once the warranty ends. Thoughts on just running AMSOIL Signature Series 5w30? Mobil 1? I don't mind having separate oils for different applications but also won't turn down being able to use same oils across different applications to save myself some money.
I've used left over Royal Purple 10w-40 as that's what I had for my race car. It definitely doesn't burn off like straight 30 weight or regular 5w-30. Definitely go heavier weight synthetic oil.
 
I'm not sure what the difference is between the Kawasaki FS651V vs the FR651V...but in my manual it says the following for the FR651/FR691V. Considering I'm mowing in above-freezing temps and spend more time mowing when it is 95F out rather than 40F... I'd lean towards a 5W-40 or 10W-40.

These air cooled engines get pretty toasty, so I don't mind throwing some premium oil at them especially since it only 2 quarts with a filter change.
1772469212537.webp
 
I've run my John Deere D140 on 10w-30 and 15w-40 for eleven seasons. It was 15w-40 RT6 for the past 4+ seasons but now I am going back to Mobil 1 High Mileage 10w30. Everything in my OPE fleet can run 10w-30 so this is basically an oil stash consolidation move. Being retired now I have the flexibility to mow only when it is cool enough to do so. Barring some cataclysmic climate change you won't find me mowing when it above 85 F.
 
Amsoil is great but I would say it's overkill for this type of application. You should be changing the engine oil at least once per season and unless you're doing commercial work you're probably not putting enough hours on the machine to use up a long-life engine oil.

I would look for a quality 40 grade engine oil like a 5w40 - 15w40. The Kawasaki is pressure lubricated with a filter and probably has 4x the running hours between changes compared to the flat-head B&S.

How many hours do you expect to run on each machine per season?
The john deere will be used weekly during summer to mow approx .25 acre lot. The kubota is used weekly during summer mow approx 1.5 acres. I believe it equates to approx 20 - 30 hours every year on each mower. I set throttle between quarter and half of max position on both. The total amount of hours depends on weather. I will let grass get tall before I mow wet grass so sometimes weekly doesn't happen and it gets a little taller than usual. I use them to mulch leaves from oak trees during fall. Each mower always gets blown off after use with leaf blower and I let them idle a brief moment before parking at end of mowing.

I replace spark plugs, air filters, oil filters, fuel filters, and oil start of every season for all ODPE.
 
The john deere will be used weekly during summer to mow approx .25 acre lot. The kubota is used weekly during summer mow approx 1.5 acres. I believe it equates to approx 20 - 30 hours every year on each mower. I set throttle between quarter and half of max position on both. The total amount of hours depends on weather. I will let grass get tall before I mow wet grass so sometimes weekly doesn't happen and it gets a little taller than usual. I use them to mulch leaves from oak trees during fall. Each mower always gets blown off after use with leaf blower and I let them idle a brief moment before parking at end of mowing.

I replace spark plugs, air filters, oil filters, fuel filters, and oil start of every season for all ODPE.
I appreciate your diligence and care towards your equipment an property. You have my thanks and respect. :D
 
I use the Amsoil small engine oil in my mowers. Works good for me. The kubota gets AMSOIL Signature Series 5w40.
 
The john deere will be used weekly during summer to mow approx .25 acre lot. The kubota is used weekly during summer mow approx 1.5 acres. I believe it equates to approx 20 - 30 hours every year on each mower. I set throttle between quarter and half of max position on both. The total amount of hours depends on weather. I will let grass get tall before I mow wet grass so sometimes weekly doesn't happen and it gets a little taller than usual. I use them to mulch leaves from oak trees during fall. Each mower always gets blown off after use with leaf blower and I let them idle a brief moment before parking at end of mowing.

I replace spark plugs, air filters, oil filters, fuel filters, and oil start of every season for all ODPE.
It would be better to run the engines at a higher RPM as they are air cooled. Running at lower RPMs deprives them of air flow for cooling. Heat kills.
 
Straight from the Kawasaki update school book. Looks like a 50 grade would better for your application.

View attachment 326708
Just saw your post of this image from my generator post. Definitely going to swap to 15w50 or 20w50 this season over the 10w40 in my kawasaki powered zero turn. Whatever I end up getting will go in the john deere for convenience.
If you check the users manual there is probably a reference to throttle for engaging and operating the PTO / mower.
I just checked and see that now. Guess that's what I get for not reading that section, lol.
 
I run 15w-40 full synthetic in my rider changed every season
I have an ohn Deere x380 with the Kawasaki engine. It calls for 2.2 quarts of 10w30. This year I'm trying amsoil for 2 quarts and topped off with last year Kawasaki 20w50. I may run slightly thicker oil next year but the John Deere book states 10w30
 
Straight from the Kawasaki update school book. Looks like a 50 grade would better for your application.

View attachment 326708
This! The engine manufacturer has come out and updated their recommendations. If you are mowing in above freezing temps, you should be running 10W-40 at a minimum and preferably 20W-50. I burned up my Kawasaki FR730V in under 100 hours by following the original 10W-30 recommendation.
 
About that time to put in fresh oil for the season. I have a zero turn with a Kawasaki FS651V that I currently run KTech 10w-40 until my warranty is up. I inherited an older John Deere GX85 with a B&S. It has sat for many years. I am going to freshen it up to use and was curious what people thought would be a good oil to run. B&S states a synthetic 5w-30 is best (https://www.briggsandstratton.com/en-us/support/faqs/mower-oil-type-and-capacity). I was thinking a 10w-30 synthetic would be better in my area due to the high temps. I run mowers in the spring, summer, and fall. The ambient temp range during those seasons is from 40s to 115 heat index. I was looking at amsoil 4 cycle oil for the John Deere and will possibly put the zero turn on that once the warranty ends. Thoughts on just running AMSOIL Signature Series 5w30? Mobil 1? I don't mind having separate oils for different applications but also won't turn down being able to use same oils across different applications to save myself some money.
5-40 or 0-40 Euro synthetic. I ran 0-40 in my 61” Z turn this last year and it was very happy. Didn’t use any oil all season.
 
J.D. D130 : 22 H.P. B&S Twin-Cylinder . Always use 5w-30 full synthetic . Mostly PENNZOIL Platinum . Others are SHELL Rotella Gas-Truck ( red bottle ) and last 2 have been PENNZOIL Ultra Platinum 5w-30 . Change every season in late October or early November then place in storage until spring . Close to 650 Hours since new . Always use non Top Tier 90 w/o E.
 
Last edited:
Back
Top Bottom