Strange. Valve seals maybe? If it has them

I assumed overfill caused by a slight mis-positioning of the dip stick. The tractor is nearly 14 years old and has been service many time.

Assumption is in one of the services the dipstick got bent (?), raising the cross hach so the middle is now the top if it was in the original position. OR about an eighth of an inch higher than it should be.

Knuttle - something is awry.. white smoke = oil. Black smoke = fuel. Are you sure about smoke color ?

Oil level check with small engines can be with dip stick screwed in or just resting on the tube. Easy to get confused so best to check the engine manufacturer's manual.

For the Kohler CV15S in your LT155 here is the procedure for checking oil level from the Kohler manual...

1. Make sure the engine is stopped, level, and is cool so the oil has had time to drain into the sump.

2. To keep dirt, grass clippings, etc., out of the engine, clean the area around the oil fill cap/dipstick before removing it.

3. Unthread and remove the oil fill cap/dipstick; wipe oil off. Reinsert the dipstick into the tube and rest the oil fill cap on the tube. Do not thread the cap onto the tube.

"white smoke = oil. Black smoke = fuel."

Depends on the light you are viewing it in. ;-)

In my shed when I start the tractor it looks black, as there is very little light.

If I see smoke when I am mowing, it is usually when returning to normal speed after the tractor sits in low speed for a couple minutes; It is white to light gray.

Hear you on the light level thing :) but, that could still be fuel related from choking cold engine to start. OTOH, if yer seeing white/gray smoke when outside, that's oil smoke.

JAL brings up an interesting point on correct way to chk crankcase oil with dipstick - also got into that bramble bush between tractor mfgr and engine mfgr about 3 yrs ago - tractor mfgr said exactly as JD perscribes for yer 155 but engine mfgr sez nope, fully screw down the dipstick. Never did get them to agree, so ended up keepin my oil level about midway in the good zone and ain't had no trouble. yep, twas a Kohler engine. Go figger.

BTW, how many hrs you got on that engine now? Might it be she's loosening up a tad?

There is no hour meter on the mower, but.....

While Dad had the mower for about 3 years, we both mowed about 0.6 acres so I assume there are about 250 to 300 hours on the tractor, I have read the engine is good for 1000 to 2000 hours, so It is relatively new.

I do all of my service and very careful that every thing that is required is done.

Did you do your traction belt yet?

I am looking forward to doing it ;-)

Like every thing else study it until you know it, carefully remove what is necessary, make sure the belt goes back the same way, and lastly and most important, make sure there are no left over parts

Deere has made it more difficult than it really needs to be, but you will get through it. The most challenging part is pulling and reinstalling the springs.