I have a Ariens rear engine 13 Horsepower mower. It is a 2001 model. It has starting using oil. The oil starts turning black after 2 hours of usage. When I pull the dipstick to check the oil level its not totally black but some black will be on the bottom of the stick. The mower seems to run perfect except for this issue. I t will use approx. 4-6 ounces of oil after 3 hours of usage. I use valvoline 30 weight oil. This just became a issue this summer. Any ideals what's going on? My spark plug has some black carbon build up on it but its dry. Is my engine getting to hot? ANY suggestions would be greatly appreciated.
Thank you
David Hayes
Marion, Louisiana

Sounds like it may be getting hot. But of course the black on the plug says its running rich... what brand engine?

It's a 13 horsepower briggs stratton engine 28000 series. What would cause it to be to hot? The carburetor has never been adjusted. Its on a Ariens rear engine lawn mower. It seems to run fine. Any info. Is appreciated.
Thank you
David Hayes

Don't think this year is able to be adjusted, usually if it is, it'll have a little screw at the bottom of the carb, screwed up into the float bowl nut (holds the bowl on) 28000, side valve or ohv briggs?

It's a 13 I/C Horsepower engine. There is no adjustment on the bowl. There is a idle mixture adjustment. I do not know if it is ohv or side valves. What would cause it to run hot?
Thank you
David Hayes

Well that's about the oil consumption part, if it was a ohv engine, it would have a cover right on the front of the head stamped OHV, right there at the spark plug... usually the head gasket goes and makes them use oil. A side valve would be more either valve stem seals, which would only make it burn a little oil at startup (from the leak after setting) or a faulty breather maybe. Usually what would cause these engines to run hot is clogged cooling fins... just a generally dirty engine all around the outside.

Thanks for the info. I will check the cooling fins and also try and narrow down what type of engine it is.
Thank you
David Hayes