What is the best product to use to clean a Kohler porcelain sink. I have water spots and Kohler says to use nothing abrasive

Here I show you how to care stainless steel sinks:

• Clean stainless steel at least once a week.
• Always apply stainless steel cleaner/polish with a nonabrasive cloth or sponge, working with, not across, the grain.
• Do not use steel wool, wire brushes or abrasive sponge pads. Use only non-scratch cleaning pads.
• Cleaners containing chloride (bleach) are not recommended. If used, rinse the surface immediately to prevent corrosion.
• Most stainless steel products will scratch from everyday use. However, these scratches will blend over time to create a unique finish.
• Do not store open containers of cleaners or chemicals such as acids, bleach, sodium chloride, lye, toilet bowl cleaner, drain cleaner, or hard water stain removal products under your sink.

Cleaning directions listed pertain only to their corresponding material and don't seem to be meant for regulator cleansing. regulator cleansing directions for chrome and vitreous china.
Success with cleaners and procedures depends upon such factors because the hardness and temperature of the water, using exact measurements of ingredients, changes in cleaning formulas and therefore the condition of the merchandise being clean. Since there are variations at intervals these factors, Kohler cannot guarantee the effectiveness of the formulas mentioned.
Allowing water to evaporate on metal will form water deposits. To avoid this and keep your product looking beautiful, it is important to wipe the sink clean with a soft cloth after each use.

You can use Kohler cast iron kitchen sink cleaner, available on line, Jacuzzi recommends warm water, mild non-abrasive liquid soap for everyday cleaning and Barkeepers Friend or Zud for tougher stains. No Abrasives whatsoever. like Comet etc.

ooppss.. welcome to beautiful black porcelain..
How to Remove Scratches in Black Porcelain Sink eHow
Fine scratches on Kohler sink
How to Make My Black Porcelain Sink Shiny eHow
Kohler Kitchen sink scratch repair

Scouring powders or cleansers contain abrasives commonly used to clean and remove stubborn stains that are slow to respond to chemical action alone.

However, use of an abrasive cleaner may scratch and damage smooth finishes such as porcelain, fiberglass or enamel making it even more difficult to clean the surface in the future.

New kitchen and bathroom fixtures do not require a scouring cleanser to clean them of soap films and body oils. Dissolving soil by soaking with the correct non-abrasive cleaner (especially a foaming type that sticks to the surface) then wiping and rinsing usually does the job.
When cleaning older, abused fixtures, choose the mildest abrasive cleaner available such as a Soft Scrub -type product or baking soda, and apply just enough that, with light pressure, the embedded soils are loosened and may be rinsed away.

Kohler makes their sinks standard, and most all sinks are the same size hole, yes it will fit.

The best product I have found to remove water spots is a product called A-maz water stain remover in a 14 oz tub. There is no magic "wipe on,wipe off" product that I have found. Initially it is a little labor intensive but this is amazing stuff and can return your sink to its original luster.

This company also make a sealer but I have not tried it. A couple of alternatives might be Rain-X or Maguires auto wax. The concept here is to put a barrier down that will seal the pores of the sink and make it easier next time to remove the spots. My favorite is Maguires about every 3 months. I have provided a link below to the A-maz web site where you can find a distributor nearest you.

http://www.a-maz.com/

try CRC

Depending on how old your sink is or how hard your water is, you may have an issue with mineral build-up on the bottom of the sink. If it's calcium, it would be white, so you wouldn't be able to see it. This sink is porcelain, so it isn't porous and should feel completely slick to the touch, especially when wet.

If it isn't, try cleaning it with a melamine sponge. There are various brands. They are all white rectangular squares and come with names like Magic Eraser (it's all the same stuff). This is a very fine but hard abrasive that should be able to clean off any film. If you continue to have issues, you can also use a cleaning product formulated to remove soap scum (like Scrubbing Bubbles).

Using soft scrub or some brand similar is the best thing to use. Manufacturers reccomend only soap and water, but soft scrub is best. Be sure to never use abrasives on any fixture, it will scratch and void warranty
Kohler makes a cleaning agent for cast iron sinks, if this is what you have.

hope this helps

Kohler does have a porcelin touch up or you can get it at Home Depot or Lowe's. Not the best solution but it might help. Comes in a little bottle like White out
Kurt