Replace or substitute formula maybe? Not sure what one to use?

Hi, I'm having a problem with some data i'm trying to work on.. heres the deal..

The word 'OK' is in a selection cells

Like this for example

A........B.......C
OK..............OK
OK.....OK
OK


Each word OK represents the number 2. How do i get the total of the number in say cell D. For example in D1 the total would be 4, D2 would be 4 and D3 would be 2. What formula would i use to do this?

I tried using the substitute and replace formula but they do not work when there is a blank value in a cell. I need a formula that i put to all three cells in the row to gain a total.

Any help would be appreciated
Thank you.

Try this formula in D1 copied down

=COUNTIF(A1:C1,"OK")*2

Perfect.. Thanks alot..