Coolant Test
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From: Ball Ground, GA
Coolant Test
It's about time for another long, contentious coolant thread...
From a DIY automotive web site:
"Automotive coolant contains many additives. There are anti-foaming agents, lubricants, seal conditioners, corrosion inhibitors, and anti-electrolysis agents. As coolant ages, these additives wear out. Each of these additives prevents damage to critical engine parts. However, the one you want to test most often is the anti-electrolysis agent. Once that agent is exhausted, the dissimilar metals in the cooling system begin swapping electrons, causing significant and costly damage. Early heater core failure, for example, is most often caused by electrolysis. As you know, replacing a heater core in most late model cars involves removing the entire dash, evacuating the A/C system and the complete disassembly of the heater box and ductwork. That’s every bit of a $1,000 repair. You can prevent it by regular coolant changes.
Want to test for electrolysis in your coolant? Here’s the simple test: Using a digital multimeter, set it to read 12 volts DC. Attach one of the test leads to the negative battery terminal and submerse the other end into the coolant. Rev the engine to 2,000 RPM and reads the voltage on the meter. Any reading over .3-.4 volts indicates that the coolant is conducting too much electricity. Either the coolant needs replacing or you have a grounding problem in the vehicle. If the coolant is fresh, check for poor ground connections between the engine and the firewall and the engine and the negative battery terminal. ©, Rick Muscoplat "
So, what color coolant is best?
From a DIY automotive web site:
"Automotive coolant contains many additives. There are anti-foaming agents, lubricants, seal conditioners, corrosion inhibitors, and anti-electrolysis agents. As coolant ages, these additives wear out. Each of these additives prevents damage to critical engine parts. However, the one you want to test most often is the anti-electrolysis agent. Once that agent is exhausted, the dissimilar metals in the cooling system begin swapping electrons, causing significant and costly damage. Early heater core failure, for example, is most often caused by electrolysis. As you know, replacing a heater core in most late model cars involves removing the entire dash, evacuating the A/C system and the complete disassembly of the heater box and ductwork. That’s every bit of a $1,000 repair. You can prevent it by regular coolant changes.
Want to test for electrolysis in your coolant? Here’s the simple test: Using a digital multimeter, set it to read 12 volts DC. Attach one of the test leads to the negative battery terminal and submerse the other end into the coolant. Rev the engine to 2,000 RPM and reads the voltage on the meter. Any reading over .3-.4 volts indicates that the coolant is conducting too much electricity. Either the coolant needs replacing or you have a grounding problem in the vehicle. If the coolant is fresh, check for poor ground connections between the engine and the firewall and the engine and the negative battery terminal. ©, Rick Muscoplat "
So, what color coolant is best?
Three Wheelin'
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From: In the boatyard installing the mast and engine, we don't need a crane, we harness the mesquito's! Yeah!
Nordschleife Master
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From: Orange, Cal
Why not just measure the resistance?
Back when I was doing a lot of 928 shopping I bought a bottle of coolant PH test strips from NAPA, but found most of the cars I looked at had recently changed coolant and/or oil.
Back when I was doing a lot of 928 shopping I bought a bottle of coolant PH test strips from NAPA, but found most of the cars I looked at had recently changed coolant and/or oil.
Three Wheelin'
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From: In the boatyard installing the mast and engine, we don't need a crane, we harness the mesquito's! Yeah!
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From: Park Hills, KY
OK, dumb question for this audience.
I bought an 84 928S US spec last year. the PO had the TB/WP/thermostat/hoses, etc replaced. I am about to replace the elec fan temp switch and the another hose. the workorder did not specify but I called the garage that had done the work. the guy said they used Texaco green, since that is what is called for.
what are good options to get that would be compatible with this? I have read other coolant threads but they confuse me on this point. as you can see by my avatar, a 20 yr air cool guy.
I bought an 84 928S US spec last year. the PO had the TB/WP/thermostat/hoses, etc replaced. I am about to replace the elec fan temp switch and the another hose. the workorder did not specify but I called the garage that had done the work. the guy said they used Texaco green, since that is what is called for.
what are good options to get that would be compatible with this? I have read other coolant threads but they confuse me on this point. as you can see by my avatar, a 20 yr air cool guy.
Race Car
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From: Mechanochondriacism
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From: New York
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or you have a grounding problem in the vehicle.
I think Wally's last question sort of pokes fun at this, but it does sound like it might have some merit.
Would it work with a batt maintainer hooked up?
