Re: Cold Weather caution
Posted: Mon Dec 28, 2009 2:13 pm
If Comma Xtralife red is a typical OAT coolant, then the presence of OAT corrosion inhibitors should not invalidate hydrometer measurements of anti-freeze strength, as the Comma product, at least, still uses ethylene glycol as its anti-freeze agent/main constituent, with a specific gravity of 1.125. Presumably, red/orange anti-freezes, with OAT addiitives, will all tell you whether or not they are ethylene glycol based, and how to measure their strength in solution.mikeonb4c wrote: >
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1) The device is a hydrometer whose measuring scale is based on the assumption that a material of SG 1.125 approx is used as antifreeze in the coolant mix.....
2) ..............It does not measure pH for example, but merely tells you what % of ethylene glycol you may have present in your coolant, assuming you have only ethylene glycol in the mix. If you happen to have used OAT, or if you've added Motormax, its readings may lead you to believe your degree of protection is low when it isn't.....
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Similarly, as MotorMax has a specific gravity very close to that of water, and is ph neutral/chemically non-reactive, its presence in your coolant mix should not invalidate the use of ethylene glycol strength-detecting hydrometers, in the usual way. As I said, if MotorMax is added as part of a full coolant replacement job, then all you have to do is make sure it replaces some of the water in the mix, not anti-freeze, and you'll still have a full anti-freeze strength coolant mix, anyway.