I have M1 5w30 on hand for my two GM cars, so that's what goes in the Honda mower, the 30 year old Tecumseh mower, and the 40 year old B&S rototiller. Never had a problem with any of them.
Oil for older B&S engines
- Thread starter wayne55
- Start date
I am currently using some form of 15w40 or 5w40 in all of my small engines. Mostly Schaeffer
Shell Rotella T5 in 10W-30…
rotella.shell.com
Shell Rotella T5 Synthetic Blend
Shell Rotella® T5 Synthetic Blend Heavy Duty Diesel Engine Oil combines synthetic blend base oils and advanced additives to deliver excellent protection.
rotella.shell.com
I use 10w-40 in all air cooled OPE that I own or service. Been using SuperTech but WalMart doesn't stock it anymore. Thankfully, I can order on-line and pick it up at the store in three days.
Probably why Harley recommends a 15W-40 HDEO if a 20W-50 “motorcycle” oil can’t be found. I run Rotella T5 10W-30 blend or a Euro 0W-30 in all OPE(though that will change in CA soon enough) I touch.Rotella 15W-40 may also a good choice. But to say any 10W-30 is "fine" may not be correct. The HTHS (viscosity at high temp) of 10W-30 oils can fall far short of straight 30. I lost 2 Honda water pump engines due to XW-30 conventional oils. I simply switched to Mobil 1, 15W-50 and the problem was solved.
The issue became clear when I understood that XW-30 oils may not be designed to have adequate viscosity at the operating temperatures of some air cooled engines.
10w30 HDEO works fine, farm & fleet stores house brand is relatively cheap.
I used M1 5W30 in my B&S for a lot of years. Once it was older I used M1 HM 10w30 to cut down on consumption.
just my $0.02
just my $0.02
- Joined
- May 28, 2014
- Messages
- 2,076
I've been using 5w30 with no issues. There was one time I used Amsoil 0w40 4 cycle. 🤷
I've used left over topoff oil in my Briggs it 15 years old and it's running great. I change it twice a year.
I run 5w30 synthetic in mine, burns no oil, atleast nothing noticeable by the end of the season
Just to pile on, you can likely find SAE 30 at the hardware store.
I used to use Pennzoil SAE 30 (detergent) in my B&S powered mini-bike.
I used to use Pennzoil SAE 30 (detergent) in my B&S powered mini-bike.
I bought a case of Rural King 30 grade a few years ago and that’s what I’m using, along with the leftover 15w-40 from when I change my tractor oil. I can’t tell any difference other than perhaps it might burn a tiny bit more of the multigrade.
Those sorts of charts have never made a lot of sense to me. Isn't a SAE 30 a SAE 30? As in, all three of those oils will be within the same viscosity range at operating temp? Why is the 10w-30 only rated up to 40F? What's so magical about 40F?
Beyond that, the SAE viscosity specs are actually separate. For example, there's not a 10w-30 spec, but rather a 10w and a 30 spec. So by definition, the 10w-30 meets the same exact specs that the straight 30 does. Put a different way, the manufacturer of the 10w-30 could literally market that oil as straight 30 if they felt like it, and they'd be completely legitimate in doing so. Same thing with all Xw-30 oils.
I wonder if the assumption is that the straight 30 is some sort of heavier base oil or something like that. But why would that be better than say... a semi-synthetic SP rated 10w-30?
Practically speaking those little engines are **** near indestructible on just about any motor oil, so it's not worth worrying about. 40 weight, 30 weight, multigrade, it all works just fine and the engines last a very long time.
Shortly after I bought my small push mower with a BS, I got fed up with my mower's auto-correcting throttle and wired it to run wide open all the time. About the same time, I got tired of going out and buying small engine 30 weight so I began filling it with M1 FS 5w30.
This thing has lasted me 17 years, granted only about an acre of grass, running wide open, cutting thick english ivy, hitting rocks that stall it out, being ran dry and locked up once (tilted it the wrong way to change the blade).
It finally started using oil and it comes out greyish so now it gets 20W50 and yes it drinks the gas now. They're probably garbage now like everything else, but these engines were apparently extremely durable at one time.
This thing has lasted me 17 years, granted only about an acre of grass, running wide open, cutting thick english ivy, hitting rocks that stall it out, being ran dry and locked up once (tilted it the wrong way to change the blade).
It finally started using oil and it comes out greyish so now it gets 20W50 and yes it drinks the gas now. They're probably garbage now like everything else, but these engines were apparently extremely durable at one time.
No, an oil with VII cannot be marketed as a monograde unless the SAE labeling requirements are ignored. They would not be legitimate in doing so. However a 30W oil without VII that meets the cranking and pumpability requirements for a 10W winter rated oil can be labeled either way.
In your example above a 10W oil is not a multi-viscosity oil. You’re mixing two different grading systems and conflating them with winter ratings.
I ran my B&S mower on Castrol Edge 0w30 A5/B5 for years without any issues. This forum taught me the error of my ways and now I just use any A3/B4 oil I can get my hands on.
No, I'm not.
The SAE requirements are viscosity specs- 30 means it has a minimum viscosity at 100C of 9.3 cSt, a maximum viscosity less than 12.5 cSt, and a HSHT value of 2.9 or higher. That's IT. Nothing to do with viscosity improvers, cold weather performance, and so on.
The 10w spec is a separate one that oils labeled as 10w have to meet, and it's mostly measured at low temps.
SAE Viscosity Grades – viscosity table and viscosity chart :: Anton Paar Wiki
Find viscosity tables and charts for SAE viscosity grades (viscosity and density values with their source).
OVERKILL
$100 Site Donor 2021
You are missing this bit:No, I'm not.
The SAE requirements are viscosity specs- 30 means it has a minimum viscosity at 100C of 9.3 cSt, a maximum viscosity less than 12.5 cSt, and a HSHT value of 2.9 or higher. That's IT. Nothing to do with viscosity improvers, cold weather performance, and so on.
The 10w spec is a separate one that oils labeled as 10w have to meet, and it's mostly measured at low temps.
SAE Viscosity Grades – viscosity table and viscosity chart :: Anton Paar Wiki
Find viscosity tables and charts for SAE viscosity grades (viscosity and density values with their source).wiki.anton-paar.com
There is more to SAE J300 labeling requirements than just passing the viscosity tests. And yes it is about VII.No, I'm not.
The SAE requirements are viscosity specs- 30 means it has a minimum viscosity at 100C of 9.3 cSt, a maximum viscosity less than 12.5 cSt, and a HSHT value of 2.9 or higher. That's IT. Nothing to do with viscosity improvers, cold weather performance, and so on.
The 10w spec is a separate one that oils labeled as 10w have to meet, and it's mostly measured at low temps.
SAE Viscosity Grades – viscosity table and viscosity chart :: Anton Paar Wiki
Find viscosity tables and charts for SAE viscosity grades (viscosity and density values with their source).
Last edited:
Similar threads
