Synthetic oil bad in a lawnmower? Any truth in this self proclaimed experts statements?

[DuckRyder]

It isn’t break in but the manual has some specific advice about change intervals.

I’ve come to like the Honda oil for no others real reason than it’s the right amount and you don’t end up with partial quarts sitting around .

 

[Schandyman]

It isn’t break in but the manual has some specific advice about change intervals.

I’ve come to like the Honda oil for no others real reason than it’s the right amount and you don’t end up with partial quarts sitting around .

12oz seems a little shy of what any ope I ever owned would take. 16-20oz is what I'm used to. What hp engine is that?

 

[Cherrybomb]

I have a 10 year old Toro snowblower,change oil every season,use 10w-30w Amsoil,last year did an oil analysis, for _hits and giggles,sample came back absolutely perfect.I think good oil,keep it fresh and clean air,remember no air filter goes a long way.

 

[kschachn]

I have a 10 year old Toro snowblower,change oil every season,use 10w-30w Amsoil,last year did an oil analysis, for _hits and giggles,sample came back absolutely perfect.I think good oil,keep it fresh and clean air,remember no air filter goes a long way.

If anything the singular UOA shows you have a "good" engine and operating conditions, not so much about the oil.

 

[Schandyman]

I got 20+ yrs and ran till the day I sold my house out of an old flat head tecumseh just using a reputable 5 or 10w30.

 

[Silver]

I have a little 3hp or so B&S powered push mower.

Shortly after I got it, maybe after 5 or 6 cuts, I got irritated with the little spring controlled throttle mechanism that increases throttle when it gets into deep grass then lets off. I took the spring and twisted it, resulting in the engine running WOT all the time. I'd guess it about doubled the rpm it was designed to run at. At that same time I got fed up getting "mower oil" for it and started using M1 synthetic 5W30 I already had.

This mower has lasted me going on 18 seasons wide open. It has just now started burning enough oil that I have to add some during the season. Granted I have a small yard but it has cut english ivy about 8" thick, hit stumps, rocks, etc. It's been locked up due to sitting on its side just before cranking, freed and mowed for 10 more years. I simply am astonished at how tough it's been. I've got to credit the oil with at least part of that.

 

[Donald]

I use synthetic in all my small engines and never a issue and will keep using it.

I do also. I think in some case synthetic oil is preferred especially in lawn mowers. Your OPE engines are air cooled by fins. Fins are often covered with grass or mouse nests. So maybe not so good at cooling. Never measured the actual temperature but I would assume they often run hot, so synthetic oil would be preferred.

 

[Donald]

I have a little 3hp or so B&S powered push mower.

Shortly after I got it, maybe after 5 or 6 cuts, I got irritated with the little spring controlled throttle mechanism that increases throttle when it gets into deep grass then lets off. I took the spring and twisted it, resulting in the engine running WOT all the time. I'd guess it about doubled the rpm it was designed to run at. At that same time I got fed up getting "mower oil" for it and started using M1 synthetic 5W30 I already had.

This mower has lasted me going on 18 seasons wide open. It has just now started burning enough oil that I have to add some during the season. Granted I have a small yard but it has cut english ivy about 8" thick, hit stumps, rocks, etc. It's been locked up due to sitting on its side just before cranking, freed and mowed for 10 more years. I simply am astonished at how tough it's been. I've got to credit the oil with at least part of that.

It's called a governor. Keep the RPM constant when load changes. You should not have messed with it.

And if you have a generator, definitely don't mess with the governor. Needs to run exactly 3600 RPM regardless of load.

 

[ARB1977]

My Honda 160 has been strong for the last 14 years. Nothing but leftover synthetic from oil changes. Mostly 5W30. I did run Amsoil small engine for 3 years.

 

[350Rocket]

I do also. I think in some case synthetic oil is preferred especially in lawn mowers. Your OPE engines are air cooled by fins. Fins are often covered with grass or mouse nests. So maybe not so good at cooling. Never measured the actual temperature but I would assume they often run hot, so synthetic oil would be preferred.

It was hot enough to blow the head gasket on my 81 11hp Briggs. It got replaced over the winter and I've been using it for hauling stuff on our property for yard work the past month. I just drained the 30w the mechanic that did the head gasket put in and m1 0w40 is going in. Hoping to get another 40 years out of it. Lol.

 

[Silver]

It's called a governor. Keep the RPM constant when load changes. You should not have messed with it.

And if you have a generator, definitely don't mess with the governor. Needs to run exactly 3600 RPM regardless of load.

Oh it's the smartest thing I could have done. It operated like a tool from Harbor Freight, afterwards it cut like there's no tomorrow and as I've said, it's lasted way beyond what it should have.

 

[Donald]

Oh it's the smartest thing I could have done. It operated like a tool from Harbor Freight, afterwards it cut like there's no tomorrow and as I've said, it's lasted way beyond what it should have.

I am not so sure. A blade flying around at an RPM higher than it was designed for?

My Toro Timemaster has a clutch for the blades so when you let go the blades atop but engine stays running. So the engine part has no controls except a switch to shut it off. You pull the handle to start it and typically starts on first pull then when done press the off switch. No speed, choke or anything except the off switch.

 

[Silver]

I am not so sure. A blade flying around at an RPM higher than it was designed for?

My Toro Timemaster has a clutch for the blades so when you let go the blades atop but engine stays running. So the engine part has no controls except a switch to shut it off. You pull the handle to start it and typically starts on first pull then when done press the off switch. No speed, choke or anything except the off switch.

You're giving me Hank Hill vibes.

 

[350Rocket]

You're giving me Hank Hill vibes.

I don't think too many people are going to agree with your wire the throttle wide open solution lol. It's a good testament to its durability, but it doesn't mean it was an intelligent move at the time unless you didn't care if it blew up?

 

[Quantico]

My 1966 ariens snow thro has a techumseh 5 hp engine. I have used synthetic 10 w 30 oil in it for over 40 years. I bought it way used. I hope I can get another 40 years out of it.

 

[Urshurak776]

None of my current vehicles use 5 quarts of oil. So, i have some empty quart bottles labeled "Lawn mower." This quart gets leftovers for the mower. Little of this, little of that, etc.

My mower from Lowes is 7 years old (Honda engine on it.) It gets a drain and refill every Spring with this concoction. Usually all synthetic. She also gets a new air filter and maybe a spark plug every other year. Just replaced the pull rope. Broke on me this year.

Runs fine.

 

[Texcl2]

In response to the original posting. Seeing how 90% of lawnmower engines use oil splashers and have no oil pressure it seems to blow a big hole in the guys theory. Synthetic works better in pretty much everything mostly due to less thermal breakdown (or breakdown in general) and less varnish. Also shouldn’t synthetic actually be more stable and less likely to have less pressure because it’s less affected by extreme heat? Pressure has little to do with how “slippery” oil is. Of course changing your oil is more important than what oil you use by about 1000x.

 

[JohnnyJohnson]

I have been using leftover Top Off oil in my Briggs & Straton wonder how much longer the Conventional oil would have made it last? Maybe another 50 years. Boy did I mess up!

 

[ZeeOSix]

Also shouldn’t synthetic actually be more stable and less likely to have less pressure because it’s less affected by extreme heat?

Synthetic oil changes viscosity like any other oil due to hot engine temperature, so in engines with an oil pump you shouldn't see any difference in oil pressure between a synthetic and not if their KV40 and KV100 are the same viscosity.

 

[350Rocket]

I don't see any difference between straight 30 conventional when I get my ope back from my small engine mechanic and after I change it to 0w40 Mobil 1 or 5w30 Pennzoil platinum etc. They all seem to run the same other than a little easier pulling on the snowblower when it gets cold, with the synthetic 0wx