Oil weight question in lawnmower/snowblower

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I have a Toro push mower with a Briggs engine. It emits a little white smoke at startup and reads a little low on the dipstick (after a year on this OCI). I have been using my FAR G Oil 5w30 for several years. Thoughts on going to Delo synthetic 5w40?

Would that 5w40 be OK for a newer 207cc single stage Ariens snowblower that specs 5w30?
 
Most mowers or horizontal piston engines emit some smoke upon startup. This is the nature of the beast. Being horizontal allows the oil to sit in the cylinder(upon startup) as where vertical pistons allow the oil to drain down.

Some engine emit more than others but, this doesn't change the fact of its design. Use the oil that the Mfg calls for in both engines.
 
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Originally Posted By: Char Baby
Most mowers or horizontal piston engines emit some smoke upon startup. This is the nature of the beast. Being horizontal allows the oil to sit in the cylinder(upon startup) as where vertical pistons allow the oil to drain down.

Some engine emit more than others but, this doesn't change the fact of its design. Use the oil that the Mfg calls for in both engines.


I disagree with this. If this was true, boxer engines would be blowing smoke everywhere.

It doesn't matter how the cylinder is oriented - that much oil in the cylinder shouldn't exist in the first place. Somehow too much oil making it past the rings and guides.



OP, check the breather assembly. Make sure the drain holes are clear.
 
In general , I would think the snow blower would need " thinner " oil than the mower ? But I do not own a snow blower . I do own a mower .

As far as mowers are concerned , I am mainly concerned , if it starts and runs . As long as it it does not burn a lot of oil , I do not worry . If it lasts a season without adding oil , I am fine . Will drain it next season any way .
 
Originally Posted By: emmett442
I disagree with this. If this was true, boxer engines would be blowing smoke everywhere.

Not necessarily so.

Have you taken the oil sump configuration into consideration in your comments?
Typically an automotive boxer engine configuration will have a much lower sump and comparitive oil level from cylinder centerline versus OPE plus the addition of pressurized lubrication working in it's favor.

A splash lubed OPE application is much more likely to emit a puff of smoke due to the relative level of the oil sump and the likelihood of oil pooling in the cylinder bore at shutdown.

Now I don't necessarily agree that most horizontal piston OPE will smoke at start-up, but it certainly is more likely.

On top of that, the customer base is more willing to tolerate the puff coming from a lawnmower and not complain to the OEM whereas in an automotive application customers are very sensitive to this kind of performance and will not tolerate it.
 
I would be using straight 30 in the toro. The manuals usually state if you go with something thinner, expect some increase in oil consumption.Using 5-40 will not solve your minor issue. At startup, you basically have the same viscosity between the two oils.
 
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Originally Posted By: Imp4
Originally Posted By: emmett442
I disagree with this. If this was true, boxer engines would be blowing smoke everywhere.

Not necessarily so.

Have you taken the oil sump configuration into consideration in your comments?
Typically an automotive boxer engine configuration will have a much lower sump and comparitive oil level from cylinder centerline versus OPE plus the addition of pressurized lubrication working in it's favor.

A splash lubed OPE application is much more likely to emit a puff of smoke due to the relative level of the oil sump and the likelihood of oil pooling in the cylinder bore at shutdown.

Now I don't necessarily agree that most horizontal piston OPE will smoke at start-up, but it certainly is more likely.

On top of that, the customer base is more willing to tolerate the puff coming from a lawnmower and not complain to the OEM whereas in an automotive application customers are very sensitive to this kind of performance and will not tolerate it.


No, I didn't talk about sump level because the claim is that it's a function of horizontal cylinder orientation.

Lawn mower or boxer, the sump oil level is well below cylinder level. I don't follow how that contributes to the "likelyhood" oil making it's way topside of the piston and into the combustion chamber.

Do you store your lawnmower on-end, allowing the sump to fill the cylinder and eventually seep passed the rings?

Somehow, my splash lubed vertical shaft engines have NEVER smoked or used any measureable amounts oil! My vertical shaft mower was $1200 new, and I'd be pretty upset if it inherently smoked and used oil. Automotive vs small engine has little to do with it, in that respect.
 
not much science to lawn and snow blower engine.

lawn mower - any synthetic or dino, 30 weight

snow blower - any synthetic or dino, 5w30


don't worry yourself too much on what you fill with more if its overfilled. change plug air filter dump the gas put 93 octane and cut it with some engineered fuel than switch back to just the 93 octane after a few tanks
 
Originally Posted By: emmett442
Lawn mower or boxer, the sump oil level is well below cylinder level. I don't follow how that contributes to the "likelyhood" oil making it's way topside of the piston and into the combustion chamber.


Incorrect. The other poster was right. The sump on a lawn mower is barely, and I mean barely below the cylinder. Especially push mowers which is what we are talking about. If you overfill the oil just a bit, it is very likely that the oil will seep past the rings into the cylinder, causing smoke at start up. Storing the mower on an incline can also cause oil to seep into the cylinder.

OP, change the oil and put the oil level halfway between "add" and "Full" to see if its helps the smoke issue at startup. If it does, then your oil level was too high. Save the 5W30 G Oil for your snow blower and use Delo/Rotella 10W30 in your mowers for your climate.

Originally Posted By: Imp4
A splash lubed OPE application is much more likely to emit a puff of smoke due to the relative level of the oil sump and the likelihood of oil pooling in the cylinder bore at shutdown.


Correct
 
In reality....any horizontal or boxer engine start to produce that "blue startup smoke" over the time...either because cylinders gets slightly oval (there is constant weight of the pistons wich is pushing against the lower side of the cylinder wall) or because of the same reason piston rings gets thinner on the lower side...
 
Don't think too much about this - he's overfilled or tilted the mower back to hose under the deck.
 
Originally Posted By: emmett442
Char Baby said:
Most mowers or horizontal piston engines emit some smoke upon startup. This is the nature of the beast. Being horizontal allows the oil to sit in the cylinder(upon startup) as where vertical pistons allow the oil to drain down.

Some engine emit more than others but, this doesn't change the fact of its design. Use the oil that the Mfg calls for in both engines.


I disagree with this. If this was true, boxer engines would be blowing smoke everywhere.

It doesn't matter how the cylinder is oriented - that much oil in the cylinder shouldn't exist in the first place. Somehow too much oil making it past the rings and guides.
_--------------------–------------------------------------------------------------------------------------

I guess that you aren't aware of SUBARU's Boxer Engine issues and their oil usage (for years) which has been discussed on many forums including BITOG & even in a segment of "talking cars with Consumer Reports".

And what was discussed was exactly what you are refering to...orientation of the pistons & piston rings and that it may infact have to do with the orientation of the pistons.
 
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Originally Posted By: bubbatime
Originally Posted By: emmett442
Lawn mower or boxer, the sump oil level is well below cylinder level. I don't follow how that contributes to the "likelyhood" oil making it's way topside of the piston and into the combustion chamber.


Incorrect. The other poster was right. The sump on a lawn mower is barely, and I mean barely below the cylinder. Especially push mowers which is what we are talking about. If you overfill the oil just a bit, it is very likely that the oil will seep past the rings into the cylinder, causing smoke at start up. Storing the mower on an incline can also cause oil to seep into the cylinder.





The hatched section of the dipstick on my Honda GXV powered "push" mower extends well under the cylinder. No smoke, no oil consumption.

honGXV160-UH2-side2.jpg
 
My Honda lawn mower engine doesn't seem to burn nor smoke at startup and seems to keep more of its oil between changes. However, it is the only OPE engine that I've owned in 45 yrs that didn't. But that's Honda, and not typical of the rest of the industry...or it used to be that they all burned/smoked. Maybe today they're all better at this.
 
Honda makes a great engine.

I hate the Briggs and their "never change oil just fill and go" I bought my house last year and the home-owners left me the mower. I immediately drained the gas poured the oil out thru the fill spout, did a full tune up and it runs great now.

I got my heart set on a Troybilt with a Honda motor for when I am in the market for a mower. My snow blower has a Tecumseh it's probably 15 years old starts first pull every year like the day it was new. Another great engine though maintenance is key.
 
Most OPE engines that I've owned all burned oil between oil dumps. Some were just better than others. This particular HONDA engine on my mower is probably the best I've owned in terms of many things, not just the fact that it burns waaaaay less oil.

It easily starts on the first pull every time during the cutting season and on the 2nd-3rd pull after winter storage. Uses less fuel for my yard and always starts after I shut it off and restart it. It never gives me a difficult HOT restart. Never fails.

Although the new Briggs & Stratton and Tecumseh engines are much better than they used to be, they had to get with the program because I've exhausted myself & torn my rotator cuff trying to start them after winter storage or on a HOT restart along with adding more oil and fuel to them.
 
Still no fan of Briggs. I do have my Briggs running great starts first pull cold or hot restarts. 2nd or 3rd after winter storage.
 
My Briggs is to the point where I just don't even think about it anymore, almost to the point of neglect. It will get no accolades from me seeing as it is attached to a 25 year old Toro RecyclerII that uses no oil between yearly 5w30 synthetic 500ml OCI, has used the same air filter and spark plug for the past 12 of those years. I am hesitant to mention that this engine starts first pull every time no matter first start of the season or after just shutting it down to empty the grass bag. I expect more than this type of bland performance from my OPE.

IF this mower ever dies, you can bet that I will be looking elsewhere than Briggs.
 
Having owned & worked on many, many horizontal cylinder engines - from OPE to a six cylinder boxer engine Honda motorcycle, the only time I experienced oil burn on start up of a healthy engine was when the machine was parked on a fairly steep grade with the engine cylinder/head on the downward side. Otherwise, very seldom did I even see a wisp of smoke.

However, some engines do or did have an issue with smoking at startup even when new. When BMW came out with their first inline horizontal engines back in the 80s, they were famous for smoking due to oil accumulating in the cylinder while parked on the side stand.

If the OP's engine regularly smokes on startup, it's likely getting tired. I had a Suzuki ATV that had been flogged hard and long for decades that began to smoke a lot upon startup but would clear up right away once the engine warmed a bit. The cylinder on it was air cooled and close to horizontal. I suspect oil was dripping past the valve guides with that engine.

What oil would I use? Anything suitable for automotive applications albeit with a preference for something in the XW40-50 range.
 
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