Measuring Coolant mixture

[Titan]

I have a 30 year old, "Five Floating Balls" syringe-type of anti-freeze temperature estimator. Any reason this isn't still accurate to use to judge the anti-freeze protection point? Does it matter if the coolant is ethylene or propylene glycol? It's been too long since I had chemistry class, I guess.

 

[Vilan]

I think those things work by measuring the coolant density... the balls are each made of slightly different densities, so whatever floats tells you where the density is. Density stays the same forever, it doesn't evaporate or rust away, so it should still work fine.

Ethylene vs propylene I don't know. They have very similar densities but I don't know if they're close enough to act the same here.

 

[NYEngineer]

I have a prism type tester. I think it works on all types of coolant. It also checks the condition of battery acid. I premix coolant in a bucket and then add it to the system so not to have any pockets of water early on.

 

[Big Jim]

PG uses a different hydrometer. When PG was introduced, they also sold a litmus paper type tester that worked on both PG and EG. I don't know if it is still available.

 

[Titan]

Thanks, everyone.

 

[D-Roc]

Refractometer works well