My old shop's 'good enough' coolant mix finally ate through a pump seal last Friday

We always just topped off the tank with whatever generic stuff was on sale, never really tracked the concentration. Boss said it didn't matter. Came in Friday morning to a puddle and a seized pump on the old VMC. The repair guy said the pH was way off and it had turned corrosive. Cost us a full day of production and a $400 pump rebuild. I'm mixing a fresh batch with a refractometer from now on, no more guessing. What's everyone else using to keep their coolant from going bad?

3 comments

3 Comments

the_olivia2mo ago

Saw a video where a guy tests his with pH strips every week (way cheaper than a new pump).

the_fiona1mo ago

Remember when people used to test their pool water with those little color kits? My neighbor did that religiously every Saturday morning. He had this whole routine with the test tubes lined up on his patio table. It always seemed like a lot of work just to swim.

lilyo301mo ago

Holy crap, $400 for a pump rebuild because the boss was too cheap to buy a $15 refractometer? That's insane. I mean, coolant turns bad fast if you don't keep an eye on it, but I didn't think it would eat through a seal that quick. pH strips are a no-brainer at that price, seriously. I've been using those little test strips for years and never had a pump go down like that.