Wasted a whole day on a bad coolant test strip kit

Had a truck with a slow overheat. Bought a cheap coolant test strip kit from a parts store. The kit said the coolant was fine, so I spent hours checking the thermostat, water pump, everything. Finally borrowed a real refractometer from the shop next door. Coolant was totally shot. That kit cost me $25 and a full eight hour day. Never trusting those strips again. What do you guys use to test coolant?

2 comments

2 Comments

reese_hill2mo ago

Man, I used to swear by those test strips too. Figured they were good enough for a quick check. Had a similar thing happen on an old car of mine, strips said it was fine but the heater was cold. Bought a basic antifreeze tester, the little squeeze bulb kind with the floating balls. It's not lab grade but it's way more reliable than paper. That strip box is probably still in my garage somewhere as a reminder.

sandrahayes2mo ago

You know what, maybe the strips get a bad rap. I mean, did you check the expiration date on that box? I've used them for years on my own cars and never had a problem. Could be you just got a bad batch or they got left in a hot truck or something. A refractometer is overkill for most people just trying to see if they need a flush. Those strips are cheap and fast, and they work fine if you buy them from a place that sells a lot of them so the stock is fresh.