General Automotive Question:

Hi "Blurp",

You're lucky! My coolant tester has only a freezing point scale.....but,seriously, that's all I want to know. That and the weather forecast for overnight temperatures........... Apart from freezing protection, anti-freeze has a limited life because of deterioration of anti-corrosion properties of the additives. Some say two years.

As for your coolant level, I don't know the model year of your 240, but my '93 coolant tank max. line is very close to the top. I wouldn't want the coolant half an inch above that, especially when cold. I would suggest that you simply remove enough to lower the level.

Good Luck. Andy I.

Ok well even this is a big help. I know that all my coolant is at least 4 years old, maybe older. I don't think the lugnuts at the garage even checked the thermostat, they just went for the most expensive repair on the list. I don't mind changing my rad if I need to but not if I don't.

My problem, however, is overheating. I live in Canada so freezing is an issue but it never goes to -45 and if it's frozen I'll take the subway.

I'll be going after some answers tonight and let you know what happens.

blurp

On Tue, 02 Sep 2003 19:57:57 GMT, the illustrious "brackenburn" favored us with the following prose:

If your vehicle is hot, then the gauge will be over the "max " line.

This level should be measured when the vehicle has been sitting for a few hours (cold).

hope this helps, SC

In article , snipped-for-privacy@hotmail.com by blurp dropped his wrench, scratched his head and mumbled,

Unless you have a leak the concentration of antifreeze to water will be essentially constant for two years. However the pH changes as the coolant ages. The best way to measure the SG of a solution is to use a refractometer. See

for examples. The best way to measure pH is with a test strip. See for examples.

The same two types of tools are also used to ascertain the viability of brake fluid as well.

If you stick to the recommended change interval of two years or 30K miles testing is unnecessary.

Bob

As a chemist, I have doubts about the pH reading. First of all, there is no pH scale and no pH standards for a roughly 50:50 mix of water and ethylene glycol. If one ignores that quibble, the most likely effect of long use is oxidation of ethylene glycol to an acid. That would lower the pH, not raise it, but the danger level shown on the Web page is 11 - which would be very alkaline.