Testing coolant concentration with hydrometer

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sjmtlewy
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Testing coolant concentration with hydrometer

Post by sjmtlewy »

I'd quite like to test the coolant concentration in my van, as I made such a mess when I bled it that I'm not sure what ratio I ended up with. Its the expensive stuff from JK thats supposed to be the same formula as VW, so I don't want to just ditch it.

anyway.. I've got a homebrewing hydrometer that I can use to measure the specific gravity, but does anyone know roughly what it should be?

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toomanytoys
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Re: Testing coolant concentration with hydrometer

Post by toomanytoys »

Some of the modern ones dont give the same specific gravity.. so unless you know what it should be for a particular type, not going to work...
You could ake a small sample and stick it in the freezer...

BE CAREFULL and dont allow anyone to use it in there drink, eat it etc if you do............ :ok

Generally I would only top up with neat antifreeze or a pre mixed.. never just water unless thats all that was available.. if you have bled out a L or so it should be ok if it was filled with the correct amount to start...

Empty the top up tank of its contents and stick neat anti freeze in... it will eventually mix into the system as it heats and cools......

sjmtlewy
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Re: Testing coolant concentration with hydrometer

Post by sjmtlewy »

So thats on the basis that if it freezes in a domestic freezer, the concentration isnt high enough?

I lost quite a lot in bleeding badly, then ran out of coolant and lost track of what i'd added...

You've given me a more scientific idea: make up a beaker of solution to the correct concentraion (50/50), measure the SG of that and then take a sample of whats in the van and compare.

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toomanytoys
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Re: Testing coolant concentration with hydrometer

Post by toomanytoys »

Yes you could do that..

Freezer would give an indication of the mix.. place the contaner neer the door at the top (always warmest spot prob around -15 on an average upright freezer..)

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pionte
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Re: Testing coolant concentration with hydrometer

Post by pionte »

or buy one of these http://www.halfords.com/webapp/wcs/stor ... &langId=-1" onclick="window.open(this.href);return false;


and dont risk upsetting the wife by contaminating her frozen chips...... :shock:
2.5 Quad Cam Scooby engine . Westfalia California 1989

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toomanytoys
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Re: Testing coolant concentration with hydrometer

Post by toomanytoys »

Yes but they work on SG (Specific Gravity) I tested some of the different types of antifreeze I have and the "organics" dont have the same SG as std glycol antifreeze.. the -30 organic pre mixed stuff didnt show as high as the cheapo -20 mixed 50/50.. and I know its fine....

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