Brown mower oil?

[wallyuwl]

Changed the oil in the car yesterday, and decided to change it in the lawnmower as well even though it only had about fifteen or twenty hours on it (changed last fall prior to storage). Engine is a Briggs 190cc.

The oil was brown. The oil used was 5W30 synthetic G-oil. The manual says 5W30 in synthetic is acceptable. Never paid much attention to the oil color before, it is a lawnmower. I did recently replace the carb and intake manifold (and gasket) to fix some issues with hard starting and engine surging, so I wonder if those issues could have worn the oil quicker.

Is the oil color anything to worry about?

 

[GuillaumeG]

Did it smell of gasoline ? I bet the carb was flooding the engine, making it run like a potato, smoke and smell bad. That's also why it probably was a pain in the [censored] to get it started once hot, but easy to start it cold.

Burning rich polluted the oil with soot, and when it was flooded trying to warm start it, it polluted the oil with gasoline. so that's probably why it's brown and smell strong of gasoline

 

[Bandito440]

I have the same B&S 190cc on my push mower. The oil comes out brown for me too, and has since new. I change it annually in the spring, which is almost exactly 50 hours of use. The brand doesn't matter either, it's always the same dark brown color.

GC 0w-30
RT5 10w-30
RT6 5w-40

I can't imagine it's anything to worry about. I've got probably 300 hours on it now, and it's still running great and starting on the first pull.

 

[Donald]

Was the carb replacement before or after last oil change? If the carb work was after, then change the oil and see if the issue comes back.

Was it left out to get rained on?

 

[Ramblejam]

Brown oil?

 

[wallyuwl]

Didn't smell it close, but don't think it smelled like gas. Hard to tell for sure because the drained car oil had gas in it (DI engine). The carb was replaced about ten running hours ago, so some of the oil usage was before and some was after the new carb and manifold. Sounds like it isn't anything to worry about. It runs great now with the new parts.

 

[Bluestream]

The color of the oil is quite inconsequential.

 

[Oldmoparguy1]

I used to have orange oil in my rider. That's the color of the local dirt. The paper element air filter was not keeping the dirt out. I now wrap the filter with 2 layers of kitchen paper towels. Now the oil stays oil colored. The same with the push mower. Give it a try, you will be surprised.

 

[toneydoc]

Just changed the oil in my pressure washer today. It is new and had about 6-7 hours on it. Manual said change it at 5 hours. It was dark and gray and slightly streaky.
I was slightly amazed at how dark it was. Might just be break in stuff in oil.
Instructions were to run it out of gas and pour oil out thru the dipstick hole. Holds about 20 oz. Put in some fresh NextGen 10w30 and went back to work. Think I will change it again in another 10 hours or so

That engine seems like it is running wide open all the time and probably is. 20 oz of oil is fairly cheap these days.

Anyhow, I believe you that the oil was brown and I would change it also.

 

[Cujet]

Sure sounds like it was due for an oil change. It did it's job and the contaminates drained out with the oil.

 

[Lapham3]

Originally Posted By: Oldmoparguy1
I used to have orange oil in my rider. That's the color of the local dirt. The paper element air filter was not keeping the dirt out. I now wrap the filter with 2 layers of kitchen paper towels. Now the oil stays oil colored. The same with the push mower. Give it a try, you will be surprised.

That's some very good evidence! I thought the Kohler engine in my Deere rider benefited from the foam pre-filter wrapped around the paper element. I've since added similar to other engines.

 

[Bror Jace]

RambleJam: "Brown oil?"

I think I know what Wallyuwl is talking about. I did an OPE oil change years ago when the oil came out a strange brown color. I don't remember any of the specifics, just that the color was really odd. It wasn't golden, a darker amber, grey or black ... but a sickly, muddy color.

I think the oil had sat in the engine for a number of years ... but can't be sire.

 

[wallyuwl]

Yeah, it was a murky brown. Not black, which is what threw me off. It only had 15 or 20 hours on it, I changed it last fall before winter storage. Drained and refilled with FAR G-oil synthetic 5W30.

I also just put a new plug in it. The "old" plug was also replaced at the same time as the previous oil change. The plug was dark black on the electrode and even first thread or two. Seems like it was wearing quickly.

I wonder if the air to fuel mixture being messed up because of the bad manifold or manifold gasket (my guess is gasket but I replaced both), which caused the engine surging, was really hard on the oil and plug.

Now it is all fixed (along with a new carb, and switched from that stupid ReadyStart system to a primer one (involved getting a slightly different carb which it needed a new carb anyway, air filter housing, and muffler). Found one gas station in town that has E0 fuel, so I'm only using that now in my small engines.

I'll just see how it things go now.

 

[SumpChump]

I've had brown oil before in small engines. It's very likely the dirt from intake and some moisture from sitting in garages for days at a time.

 

[linksep]

I just did an oil change on the Snapper/Briggs mower, oil was a shimmery brownish color... put a STRONG magnet under the pan you used to catch the old and play with the aluminum/copper/bronze particles in the oil. Then make a note to yourself to change oil slightly more often.

 

[Bandito440]

Originally Posted By: linksep
I just did an oil change on the Snapper/Briggs mower, oil was a shimmery brownish color... put a STRONG magnet under the pan you used to catch the old and play with the aluminum/copper/bronze particles in the oil. Then make a note to yourself to change oil slightly more often.

That must be a strong magnet!

 

[linksep]

Originally Posted By: Bandito440
Originally Posted By: linksep
I just did an oil change on the Snapper/Briggs mower, oil was a shimmery brownish color... put a STRONG magnet under the pan you used to catch the old and play with the aluminum/copper/bronze particles in the oil. Then make a note to yourself to change oil slightly more often.

That must be a strong magnet!


Indeed. Non-ferrous "non-magnetic" metals can react to a magnet, google "Eddy Current", pretty cool stuff. The magnet was from http://unitednuclear.com/index.php?main_page=index&cPath=70_71 pound for pound some of the strongest magnets on earth (I also have a large supply of magnetron magnets from broken microwave ovens... strong but not as strong as the magnets from united nuclear...)

 

[TFB1]

Originally Posted By: Bluestream
The color of the oil is quite inconsequential.

Agreed(at least partially)... With a good engine & carb it should be brownish, at least if it has 25 or more hours on it... If oil is blackish, either the carb is too rich or engine has blowby(if it has blowby engine is likely using oil)...