Changing Oil 10W30 Pennzoil

I changed out 2 quarts of Pennzoil 10W-30, out of my Kohler / Cub Cadet, and it looked very thin, maybe watery-like. I change oil hot, so it was pretty hot. Oil was black, had 100 hours on it. Does it sound normal? OK? Engine has 200 hours on it.

Should only use a straight weight in a air cooled motor. 30W works really good.

Thank you, but the owner's manual says 10W-30, Grade SJ or higher. That's what I run.

There is nothing wrong with running 10W-30 in an air-cooled engine. I do know know what your issue is - if you have one. Years ago Quaker State got sued for a huge batch of bad oil that lost its vicosity when hot and many engines got ruined. I never heard of it happening again with any other brands. 10W-30 is a 30 weight when hot, just as straight 30W is. I am wondering why your oil turned black so far. Is it an engine that previously was not maintained and is dirty inside?

I have no idea. It is a fairly new Kohler, Cub Cadet GT 2550, only 200 hours. Plugs show light tan color. Plenty of power, runs and starts good. Owner's manual says change oil at every 100 hours, so I do. Does not use oil.

It depends which Kohler. The Command engines require 10w30 because they have hydraulic lifters. And from personal experience, the lifters will complain if used with heavier oils.
Black at 100 hours would not be uncommon. Let it cool off and see how thick it is. Do you smell any gas with it? Lots of those engines have problems leaking oil through the carburetor, into the cylinder where it works past the rings and into the oil while sitting.

30W was fine till the oil companies started formulating good oil. Check for a leak between the air filter and the carb,that would cause dirt to bypass the filter. I have found leaks around the filter base on 4 or 5 Kaws over the years.

I think 100 hours is a long time to run oil in a mower, just my opinion! I think most newer mowers recommend 10-30, our JD does.

Given that it is only 2 quarts - I'd change the oil more often - like at 50 hours. Its cheap insurance - and if you do have an issue with fuel in the oil you'll catch it that much faster. Black as coal at 100 hours sounds about right, thin when hot is normal too.

we used 10-30 oil and straight 30 oil all time in shop had no issues. if they used unit in fall used 10w30 if not used 30. sounds fine to me as long as it did not smell gasy

That's very interesting about Quaker State. I stopped using it something like 20-25 years ago for the reason after an oil change I had less oil pressure than with other same weight oils. I know others who had the same experience. Never lost an engine though, and haven't bought Q S since either.

The 27 hp Kawasaki engine in my Cub Cadet Tank recommends 15W-40 Rotella oil used in the engine per the manual. Takes about 2-1/2 quarts, says change oil & filter every 100 hours but I use it about 40-50 hours a year so it gets changed once a year around 50 hours.

Back when I mowed with IH Cub Cadets with K series single cylinder Kohler engines I ran 10W-40 oil, mostly Valvoline till I got my diesel pickup then used 15W-40 Rotella in them, changed every 25-30 hours. Ran one 10 hp over 1400 hours after a rebuild. It's been rebuilt again and has around 100 hours on it. Got a 14 hp Kohler that's more like a garden tractor motor that I mowed with, it gets 15W-40 Rotella synthetic. None of these engines have an oil filter. The B-48G 20 hp Onan in my 982 has a filter, I changed it around 40-50 hours with 15W-40 Rotella.

Air cooled engines run much hotter oil temps than water cooled engines, harder on oil.

Back before I rebuilt the 10 hp Kohler the last time I ran it about 14 hours straight, from about Noon till 2 AM, then two days later ran it another 12 hours. Had changed the oil the day before I ran it 14 hours, and changed it again after the 12 hour day. It's only 1-1/2 quarts of oil.