Lawn mower, 0w30, smoking on startup

[Hyrde]

Hi, I just purchased an old beat up mower with a Honda 190cc engine for peanuts.

The engine oil had brown streaks, likely some combination of fuel and water contamination.
I swapped it out with whatever I had on the shelf, which was a Shell ECT C2/C3 0W-30. I assumed it would be fine because the manual specifies 5W-30 or 10W-30 API SJ or better, and the new oil has like a trillion different approvals including API SN. Finding cheap 5W-30 or 10W-30 is almost impossible here in Norway, everything is 0W-x or xW-40 for some reason.

Anyway after changing the oil and starting it there was a huge puff of smoke and the exhaust seemed like a two stroke for what seemed like five seconds, and then everything was fine.
Is this something I should worry about or is this normal?
I did accidentally drain the carb while changing the oil, so I had to pull the starter a few times before it would fire. Could this cause the smoke? I've never owned a mower or changed the oil on it before, so I have no idea.

I tried starting it again and there was no smoke, but the engine was already warm. I'll try another cold start tomorrow and see if it still smokes.
It didn't smoke with the old oil. However with the new oil the engine runs so much quieter and better, almost can't believe the difference, but I guess that's expected considering the sad state of the drained oil.

 

[MichiganMadMan]

Did you tip it on it's side to change the oil? I have had small engines smoke like mad when they were at an angle that they aren't normally operated at.
The fuel going missing certainly didn't help the situation. When you say you drained it, do you mean it all went into the engine?

 

[Trav]

+1 this can happen with horizontal small engines when they get tilted, a small amount of oil gets into the combustion chamber and smokes, no problem.

 

[Hyrde]

Originally Posted By: MichiganMadMan
Did you tip it on it's side to change the oil? I have had small engines smoke like mad when they were at an angle that they aren't normally operated at.
The fuel going missing certainly didn't help the situation. When you say you drained it, do you mean it all went into the engine?


I did tip it over to drain the oil. The carburetor has this canister which I assume holds fuel, and fuel went running down the engine and chassis when I tilted the engine over. There was no wet spots around the tank or gas line so I just assumed it was the canister on the carb that got emptied out.

Originally Posted By: Trav
+1 this can happen with horizontal small engines when they get tilted, a small amount of oil gets into the combustion chamber and smokes, no problem.


Alright, thanks to both of you, the engine oil is probably fine then. It was very cheap (on sale, dino price) so I bought a lot of it..

 

[bubbatime]

As a general rule, I never use synthetic oil in older, un-maintained equipment. I've seen time and time again that the rings are shot and it just smokes like crazy when using synthetic. For some reason, conventional oil doesn't smoke or smokes less in worn, neglected engines.

If it doesnt smoke after the first few seconds, I wouldn't worry about it.

Also, it has a horizontal engine. If the oil level is above the bottom of the cylinder, oil will seep into the cylinder during storage, which smokes on startup. Drain some oil out of it so that the oil is halfway between full and add on the dipstick.

If it were mine, I would change the oil with the cheapest store brand conventional 10W30 I could find, and then change it again about 5 hours later, and then annually after that.

 

[CharBaby]

Double check the information on this but, typically Honda's generally prefer no gas in the carb when tipping the mower over to drain the oil. Either run the engine out of gas or use the fuel shutoff and run the gas out of the carb.

 

[Kamele0N]

Originally Posted By: bubbatime

If it doesnt smoke after the first few seconds, I wouldn't worry about it.

Also, it has a horizontal engine. If the oil level is above the bottom of the cylinder, oil will seep into the cylinder during storage, which smokes on startup. Drain some oil out of it so that the oil is halfway between full and add on the dipstick.

If it were mine, I would change the oil with......


......with xyW-40 grade of oil....I run 5w40 synthetic in all my OPE equipement WP.....synthetic because air cooled OPE equipement chews mineral or semisyn oil quite soon....and that mean oil consumption a.k.a smell of burnt oil in my nose (wich I dont like)

 

[JustinH]

My John Deere Briggs smokes for a second after starting, then doesn't smoke anymore after that.

I change the oil yearly with Delo or Rotella.

 

[Hyrde]

Originally Posted By: bubbatime
As a general rule, I never use synthetic oil in older, un-maintained equipment. I've seen time and time again that the rings are shot and it just smokes like crazy when using synthetic. For some reason, conventional oil doesn't smoke or smokes less in worn, neglected engines.

If it doesnt smoke after the first few seconds, I wouldn't worry about it.

Also, it has a horizontal engine. If the oil level is above the bottom of the cylinder, oil will seep into the cylinder during storage, which smokes on startup. Drain some oil out of it so that the oil is halfway between full and add on the dipstick.

If it were mine, I would change the oil with the cheapest store brand conventional 10W30 I could find, and then change it again about 5 hours later, and then annually after that.


Alright I'll try a different oil if it doesn't stop smoking. I just used what was left in a bottle after changing the oil on a car. I can get store brand mineral 10W30 API SL but it's a bit of a drive, I'll pick some up the next time I'm in that area. The mower certainly doesn't seem well maintained, but luckily other than the brown color streaks the drained oil seemed perfectly fine. No metal shavings or anything like that.

Originally Posted By: Char Baby
Double check the information on this but, typically Honda's generally prefer no gas in the carb when tipping the mower over to drain the oil. Either run the engine out of gas or use the fuel shutoff and run the gas out of the carb.


Good tip, I'll burn off the gas in the carb next time. I did shut off the fuel and disconnect the spark plug but I didn't consider the fuel left in the carb.

 

[xxch4osxx]

Originally Posted By: Kamele0N
Originally Posted By: bubbatime

If it doesnt smoke after the first few seconds, I wouldn't worry about it.

Also, it has a horizontal engine. If the oil level is above the bottom of the cylinder, oil will seep into the cylinder during storage, which smokes on startup. Drain some oil out of it so that the oil is halfway between full and add on the dipstick.

If it were mine, I would change the oil with......


......with xyW-40 grade of oil....I run 5w40 synthetic in all my OPE equipement WP.....synthetic because air cooled OPE equipement chews mineral or semisyn oil quite soon....and that mean oil consumption a.k.a smell of burnt oil in my nose (wich I dont like)

You must not like the smell of a 2 stroke engine running then!

 

[Kamele0N]

Originally Posted By: xxch4osxx
You must not like the smell of a 2 stroke engine running then!


I love 2stroke smell.....have 2 chainsaws..trimmer..1 scooter and 1 mofa

Smell of burnt engine oil (4stroke) is something completely different from 2stroke smell....

 

[Kuato]

If the previous owner did not change the oil it may take a few hours for everything to become normal again. I would keep an eye on the oil level, run it for maybe 20 hours, then change the oil again. It simply could be a starting up smoker...

 

[toneydoc]

Mine smokes for 5-10 seconds every time I start her.

No worries. She keeps starting

 

[OneEyeJack]

My 15+ year old Honda HRC216 mower has used left over synthetic 0w-30 oil from day one that's used in my 2 DD. I think the wheel adjusters will rust off before the engine wears out. I have not noticed that it used any oil that I can measure. I change the oil every time I refill the 5 gallon gas can and change the air filter and check or replace the spark plug, too. I've changed the small automotive fuel filter I've added when I think about it, maybe every couple of years. I've had no problems running an ester based synthetic multi-grade oil along with a PEA gas additive and regular pump gas. The mower also gets carefully spray washed after every use so that the engine does not have cooling problems because of grass and dirt sticking everywhere.

 

[Hyrde]

Sounds like you're maintaining your mower very well OneEyedJack. I've also ran whatever 5W-30 or 0W-30 API SL+ synthetic I can find on clearance in my old Toyota Echo, which was also sparingly maintained before I bought it from my sister, but it doesn't burn any oil at all between yearly oil changes (~9000 mile intervals). Luckily the gasoline over here already has stabilizers in it straight from the pump, it's OK over winter if stored in a full can or tank with the cap screwed on tight.

Despite probably seeing minimum maintenance this motor seems to run well, the rest of the mower isn't too great though. The left front wheel was extremely wobbly and upon disassembly the "axle" on the wheel mount had like 3/8" of play back and forth. Naturally the inside of the plastic wheel was destroyed from the metal drive gear. I made a makeshift shim and replaced the wheel and it seems fine now, but it seems like I need to replace the drive belt as well because it's really loose and there doesn't appear to be a tensioner. I enjoy servicing these small engine devices though, so simple and straightforward.

 

[CharBaby]

Originally Posted By: Hyrde
Originally Posted By: bubbatime
As a general rule, I never use synthetic oil in older, un-maintained equipment. I've seen time and time again that the rings are shot and it just smokes like crazy when using synthetic. For some reason, conventional oil doesn't smoke or smokes less in worn, neglected engines.

If it doesnt smoke after the first few seconds, I wouldn't worry about it.

Also, it has a horizontal engine. If the oil level is above the bottom of the cylinder, oil will seep into the cylinder during storage, which smokes on startup. Drain some oil out of it so that the oil is halfway between full and add on the dipstick.

If it were mine, I would change the oil with the cheapest store brand conventional 10W30 I could find, and then change it again about 5 hours later, and then annually after that.


Alright I'll try a different oil if it doesn't stop smoking. I just used what was left in a bottle after changing the oil on a car. I can get store brand mineral 10W30 API SL but it's a bit of a drive, I'll pick some up the next time I'm in that area. The mower certainly doesn't seem well maintained, but luckily other than the brown color streaks the drained oil seemed perfectly fine. No metal shavings or anything like that.

Originally Posted By: Char Baby
Double check the information on this but, typically Honda's generally prefer no gas in the carb when tipping the mower over to drain the oil. Either run the engine out of gas or use the fuel shutoff and run the gas out of the carb.


Good tip, I'll burn off the gas in the carb next time. I did shut off the fuel and disconnect the spark plug but I didn't consider the fuel left in the carb.


I would love to hear more about this(leaving fuel in carb) as my BIL once told me that this has something to do with the fuel in the carb on a HONDA. That, when the mower is flipped upside down, the fuel inside the carb(not what's in the gas tank), can ruin the carb when inverted. But, IDK!

 

[OneEyeJack]

I've found that using a PEA additive in the fuel gets rid of fuel related problems when the mower is not in use.

I have an Echo 2-cycle weed whacker and after mixing the ester based synthetic 2-cycle oil and gas I also add some PEA fuel additive. Before I started using PEA the carb got so plugged up that repeated cleanings just did not last. I replaced the carb, started using PEA and over 10 years later there are no problems. The plug last so long now I have to remind myself to check it. It starts on the first pull after priming almost every time even after sitting idle for a couple of weeks.

 

[Hyrde]

Well the mower didn't smoke at all today when starting it, and it runs fine. Sharpened the blade and was able to figure out how to tension the drive belt and this thing will probably service my lawn for years, great little motor.

The fuel leakage and oil seeping into the combustion chamber only seem to occur when tilting the mower past a certain angle, it seems fine when just laying it down on its side (which is not sufficient to drain all the oil out!).

This 9 year old Honda fires first pull with no choke and the pull is so light! That low compression start system really works, not just marketing there. My 190cc Briggs powered snow blower, which is a very expensive model with way fewer hours on it, needs two or three HARD pulls with the choke on.. I'll service it before summer storage.

 

[Kamele0N]

Originally Posted By: Hyrde


This 9 year old Honda fires first pull with no choke and the pull is so light! That low compression start system really works, not just marketing there. My 190cc Briggs powered snow blower, which is a very expensive model with way fewer hours on it, needs two or three HARD pulls with the choke on.. I'll service it before summer storage.


Change diaphragm in a carburator (if equipped).......and rubber O-ring where carburetor seats on maniford (possible air leak there thats why you probably have these problems with B&S)

 

[Triple_Se7en]

I've found 5W-40 synthetic best for the normal run-of-the-mill push lawnmower engines.