You DO NOT screw down the cap to read the oil level.

You rest the unscrewed cap on top of the tube to obtain accurate reading.

I didn't ride in on no load of pumpkins and I am just now having my suspicions about this confirmed.

I haven't yet measured the difference --- it is right now coming a monsoon or else I would be out there with my machinists ruler --- but, by screwing down the cap when checking, one is always about half- to 3/4-inch LOW on oil when it reads FULL.

One would think this information would be in big red letters posted all over the place and on the front and back of your favorite breakfast cereal.

Now, that bit aside, regarding a 23hp Kohler 23CVS V-Twin vertical crankshaft engine of 2006 vintage --- I have both the Owner's Manual and the Shop Service Manual right here in front of me --- how many ounces of oil are represented between Full and Add on the dipstick ?

How many between just barely touching the stick and FULL ?(with the stick screwed down)

Total capacity is stated to be two quarts.

There are several old GOOD trucks sitting out here, Chevrolet, Ford, and Dodge; and, every one of them says Add One Quart right on the dipstick; the diesels say Add Two Quarts; we have taken this useful information for granted for years and now manufacturers think we don't have enough sense to utilize such information.

There is no reference to Communist measurements, sending me looking for Metric/American conversion tables; just plain old "Quart" --- there's four of them in a Gallon.

Several of the older small engines around here say Add 8-Ounces; quite handy to know; that's a cup; half-a-pint; measure a cup and pour it in there --- no guesswork.

If no one knows this information about the Kohler, I will decipher it myself once my new oil gets here and it quits pouring the rain --- the 8-day doesn't look very promising = more of what we have had the last five.

I was mowing up a storm the other day and the dipstick unscrewed itself and jumped up out of the hole and splattered oil all over the back of the seat, probably the back of my head, and all over the engine --- I had that thing what I thought was snug enough --- I'll use a monkey-wrench or my Stilson or Channel-Locks on it from now on --- fool me once...

I will put a collar around the tube with a safety loop over the cap so it can't unscrew nor jump up.

I had no clue this was going on; had I not stopped to check the fuel level, it probably would have cost me the engine.

Okay --- curiosity got the better of me and I ran out there between lightning flashes and did some measuring.

From the bottom edge of the cap to where it seats on the tube when screwed down = 3/4"

The cross-hatched area between FULL and ADD = 5/8"

From the bottom tip of the stick to FULL = 1-inch

Thus, between ADD and the tip =3/8"

So, if one is checking with the cap screwed down instead of sitting on top of the tube, FULL is actually 1/8-inch BELOW ADD and we have been running around low on oil all the time, contentedly assuming we were FULL.

Now, back to my question --- how many ounces between ADD and FULL on the Kohler 23CVS dipstick ?

Yeah, there's clearly a problem of perspective from the person responsible for that design.

The proper way to handle things like this, is to have a sensible person audit preproduction items for operation and maintenance BEFORE they go to the assembly line, so that 'fit and finish' issues, particularly those in 'ease of maintenance' get handled well.  Kohler did NOT manage this one.  For what it's worth, my ZTR's Command twenty-something has a goofy dipstick setup too... off the top of my head, I don't recall exactly how it is, but it's less than intelligent.

Soichiro Honda's key driver of product design quality and performance, was his wife.  When he developed his first motorbike engine system, he put it on her bicycle, to help her with her run to the market and back, and each time she came back, she pointed out everything that wasn't appealing.  That was his basis for product improvement, and he continued doing that for his motorcycles, and I suspect most of his cars.

A friend of mine was an engineer at Segway, they used a similar philosophy in the development of their first products...

If EVERY manufacturer did this, products everywhere would perform better, be easier to use, harder to break, and easier to maintain... but they don't, so they aren't.

Gee Dave, one day your head will explode with all the neat knowledge you have, and the World will be in for a huge loss !!

My hunch about 'quality products' is that IF they built them..it'd be a 'one run and done' deal. Take car exhaust system. IF it was 100% SS front to back, it'd NEVER need to be replaced.

I used two levels and some hydraulic bottle jacks to get the frame dead-level in both planes.

I incrementally sneaked up on the bottom of the "SAFE" zone.

Then, I incrementally sneaked up on the top of the "SAFE" zone = Full.

Sitting dead-level, I measured 14-ounces from bottom of Safe to top.

So, on my machine at least, the Safe zone represents 14-ounces of oil.

Thanks for everyone's input and responses.