Any Partial Coolant Drain Advocates ?

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Anyone doing partial coolant drains (i.e. 1 gallon) once every 1 to 1.5 years as part of a coolant maintenance plan ?
 
I do it but because I don't want to open crusty rusty block drains. So I just do the radiator and whatever else comes out its petcock.
 
I like to do just the radiator less chance of having air bubbles and less work.. so I dont let it go 10 years where its gross.
 
Beat me to it. As long as its replaced with the same fluid it cant hurt anything. I had a 2010 Accord that I dropped 3 quarts of transmission fluid every other 10k oci instead of the recommended dropping 3 quarts and driving around the block times 3 at 60k miles. The new fluids help replenish any additives that may be getting used up.
 
I drain out about 1.25 gallons of coolant at 100k miles and then every 50k past that. Seems good enough in my Toyotas.
 
Once you open the radiator drain, you might as well do it all
smile.gif
 
I've only been doing partial D&Fs these day as I don't find it as easy to connect a "T" in the hose as it used to be, in order to do a flush.
 
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Originally Posted by slacktide_bitog
Once you open the radiator drain, you might as well do it all
smile.gif




If only it was that easy.
confused2.gif


Been doing partial drains for years.
 
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Sometimes it's the best way to do it, other times it's the ONLY way to do it!
I had a 2008 DTS for example. Took it to the dealership for a coolant change. I waited for the car. They came back to me an hour later and told me they would have to disassemble half the front end to do a drain/refill, since there was absolutely no way they could get to the lower radiator hose!
Against my better judgement, I gave them permission to use a flush machine on it. They did it right than goodness, and upon returning home my coolant concentration checked out at 50%.
Flush machines increase the possibility of introducing silicates into a Dexcool system, which is NOT GOOD.

On a 1999 Northstar STS, it was a simple process of dropping the lower rad hose and using an auto vacuum cleaner to blow out the system.
Refill with 50/50 Dexcool and good to go.

People that swear by flushes need to have the proper tool to ensure a 50/50 mixture, or whatever the manufacturer calls for. Coolant can do strange things when the mixture is incorrect.
I use a refractometer to make sure the concentration is spot on.

Ultimately you are trying to replenish the additives, so YES, drain and fill is the BEST way.
 
Partial drain and refill on all my vehicles and equipment for many years. No problems. Always in good shape.
 
Yes...I usually do a drain and refill every two years. It's less money and easier than replacing a heater core or water pump. Fresh anti freeze makes your gaskets and heater core and water pump last longer. It is so easy to do as well and I use the Lisle funnel to do it.
 
Originally Posted by user52165
Originally Posted by slacktide_bitog
Once you open the radiator drain, you might as well do it all
smile.gif




If only it was that easy.
confused2.gif


Been doing partial drains for years.


I think he meant to drain out whatever comes out of the radiator when you open the stopcock. For my Camry, it's about 1.25 gallons.
 
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