Yesterday, I tested the pH of my coolant using the below pH test strip kit recommended in an earlier thread and in the attached link, www.ehow.com/how_7872430_read-ph-antifreeze-test.html, which says the pH should be between 7.5 and 9 and found my coolant pH to be right at 8 which means my coolant is still protecting my engine and that I still have awhile to go before it is necessary for me to change my coolant, which has been in the car since Dec, 2010.
Opening the petcock at the bottom of the radiator, I drained a little of the coolant into a clean glass. It was the clear yellow color of weak beer. I took one of the test strips and stuck it into the solution for one second and shook it off and after waiting 45 seconds, compared the strip with the color chart, which matched the color pattern under a pH of 8. I took pictures of the process but the setting on my camera was too high for them to post here so if anyone is interested, send me your e-mail in a PM and I can e-mail them to you.
The (100) "colorpHast" test strips (cat.#9590) test a pH range of 0 to 14 and come in a small 2" x 3" x 1/4" clear plastic container with the color comparison chart showing through each side of the box. The unused strip next to the chart, in the photo, is 3" long x 1/4" wide. Jim Patrick
You can purchase these PH test strips at your local Drug Store. You might have to ask but that's where I get them.
You would have better luck finding pH strips at a Pet Supply store that carries fish supplies.
How about a swimming pool supply house? Owners have to check the pH level of the water periodically.