I found a few references online for using your mulitmeter in DC V mode to test the health of your coolant. One was a six year old thread from BITOG.
thread
I have one vehicle that sees little use, and when driven, is driven moderately (14k miles in the 3.5 years since I last changed any coolant, when I did the WP and timing belt as well as both radiator hoses). Since we live in a very mild climate (it rarely sees temps over 80F or under 40F), I speculated the coolant was not being stressed and didn't need a change despite the time. It has has no make-up coolant in that time and the level in the overflow tank is also unchanged. It is regular green in the system. I ran the multimeter test and got ~70mV (.07V as in the guidelines).
So, my instinct is to just monitor this value before the summer starts each year and then drain/fill the radiator, barring any visible changes, when this value starts to climb towards the threshold 0.4V. I was considering getting test strips and then read and learned about this method, which was news to me.
It's not that I am maintenance-shy; I do all my own and enjoy it. But I have less free time for that and higher priority little tasks on the cars I'd like to do first. Plus throwing out perfectly good fluid doesn't seem bright if a simple test is available.
Q: Does anyone else use this method or have experience with it?
thread
I have one vehicle that sees little use, and when driven, is driven moderately (14k miles in the 3.5 years since I last changed any coolant, when I did the WP and timing belt as well as both radiator hoses). Since we live in a very mild climate (it rarely sees temps over 80F or under 40F), I speculated the coolant was not being stressed and didn't need a change despite the time. It has has no make-up coolant in that time and the level in the overflow tank is also unchanged. It is regular green in the system. I ran the multimeter test and got ~70mV (.07V as in the guidelines).
So, my instinct is to just monitor this value before the summer starts each year and then drain/fill the radiator, barring any visible changes, when this value starts to climb towards the threshold 0.4V. I was considering getting test strips and then read and learned about this method, which was news to me.
It's not that I am maintenance-shy; I do all my own and enjoy it. But I have less free time for that and higher priority little tasks on the cars I'd like to do first. Plus throwing out perfectly good fluid doesn't seem bright if a simple test is available.
Q: Does anyone else use this method or have experience with it?
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