Testing Coolant with refractometer

[nitroman]

Hi all, has anyone tested their coolant with a refractometer? I bought this one:

Amazon.com: Robinair 75240 Coolant and Battery Refractometer: Automotive

I first checked it's calibration with distilled water, seems fine showing 0 degrees celcius. So then I start with my coolant, and I get nothing. The light shines right through and I don't see any shadow line. I test again with distilled water and it's fine, then try coolant again and still nothing. Then I tried some windshield washer fluid for fun, showed a shadow line this time (but reading was weird like -3 degrees or something, I figured the scale is just not set for windshield washer fluid). So has anyone had any luck with a refractometer?

I believe my coolant is from the stealership, so I'm guessing G12 (it's red/purple color). Is that propylene glycol? Because if so that should work. I emailed Robinair directly and they said the unit might be defective. However I'm worried that will it actually not work for VW coolant? I'm deciding whether to exchange for a new one, or all out refund it if it's not going to work anyways.

Background Context: I'm trying to test if my coolant needs replacing. I'm at around 120,000 km but I had my TB and WP done at 75,000 km at the stealership, and I assumed they replaced the coolant. However my friend mentioned they could've just drained it, replaced pump, and put the original coolant back in (do they really do that?).

Another thought, is it better to just check coolant temperature using VAG-COM instead of using a refractometer?

[IndyTom]

Why not just get a $2.00 Antifreeze Tester from your local Autozone or Autoparts Store? Or get the more expensive Prestone Tester for $6.00 either one will do probably better than your expensive refractor-machinge. http://www.amazon.com/dp/B0002JN15U?...etester.net%2F


Also I have never heard of the dealer not replacing the Coolant when doing the Timing Belt service. It is part of the service and unless they are total crooks they would always replace it. Just check your parts list from your invoice. I am sure they have charged you for it. Personally if your Timing belt service has been done I wouldn't worry about your coolant it should be fine! Also return that funky little useless tool for a Full Refund unless you want to keep on Testing Tab Water

Have a great day and a Merry Christmas.

[MyOtherRidesAVette]

Ditto to everything, including the return of your $40 tester. The receipt for the TB work will clearly show all parts itemized (including coolant). Service has to requisition it from Parts. If your missing the receipt, the Dealer has it in their computer.

M.

[nitroman]

Thanks everyone. I originally thought that the refractometer is more accurate, and I saw somewhere that even the Bentley manual mentions using one. Plus I thought I read somewhere that Prestone anti-freeze testers don't work for the VW type of coolant (is it propylene glycol?, or I should say specifically the super long life coolant type). But since it's probably no use, I'll return it for a full refund. Thanks a lot guys, merry xmas.

PS: the main reason I'm worried about my cooling system is that my wife's friend has a 2000 beetle similar mileage and something in the cooling system failed recently. I can't get the exact details since my wife nor her friend know much about cars (though I shouldn't talk I'm a noob too). I want to make sure it doesn't happen to me, so I guess I'll test the rest like check hoses, check fans, etc etc. Back to reading more of the repair guides

[IndyTom]

I have used the Ball type tester on the G12 coolant on my Audi TT's and now my New Beetle and they seem to work fairly well.
We get some cold winters here in Indiana and I want to be sure the radiator or block doesn't freeze up.

I believe that G12 still consists of a Glycol composition just made for aluminium blocks.