Why does nobody talk about coolant pH levels going off so fast

I checked my coolant tank last Tuesday after a rough shift cutting 6061 aluminum, and the pH had dropped from 9.2 to 7.8 in just 3 days. The machine was starting to get that weird smell and a little rust on the way covers. Anyone else deal with coolant going sour faster than you expect?

2 comments

2 Comments

angelac631mo ago

Oh man, the pH dropping that fast in 3 days is WILD. That's not normal at all, something is definitely off. I've had coolant go sour on me before but never that quick, usually takes a couple weeks at least. Check if you're getting tramp oil in there from the way lube or hydraulics, that stuff kills pH fast. Also make sure your concentration isn't too low, I run mine a bit richer on 6061 because the fines just suck the life out of it.

the_mary1mo ago

Seems like a lot of systems fail fast these days, not just coolants. Things are built to work right up until they don't, with no warning. You really have to stay on top of the small checks to avoid the big problems.