Any Partial Coolant Drain Advocates ?
- Thread starter ChrisD46
- Start date
This makes about as much sense as sucking a quart of oil out of your engine every 1,000 miles and replacing with new oil. Modern aluminum engines cooling systems have coolant change intervals of at least 5 years to 10 years and up to 150,000 miles. The coolant that comes out at the end of its life cycle is nearly are clean as new coolant visually. Only the chemical additives are depleted. Just do one complete and proper flush and change at the recommended interval. You don't have to mess with a rusty block drain.
JHZR2
Staff member
None of my systems, even the old cast iron engineers get dirty or nasty. So I just drain the radiator and refill.
Nobody is advocating only partially draining the easy part, which would be foolish. Draining all the easy part and then not struggling with the difficult part makes a lot of sense sometimes. Assuming it gets more than half, that's better than a thorough change half as often, and likely less labor.
The old method of multiple plain-water flushes, followed by adding the theoretically correct amount of concentrated coolant does not work when new coolant is available only in pre-diluted form.
The old method of multiple plain-water flushes, followed by adding the theoretically correct amount of concentrated coolant does not work when new coolant is available only in pre-diluted form.
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I have done a radiator only drain and fill. I do it every 1.5 to 2 years. Gets half the fluid out at a time. Then when I do it again in another 2 years the complete change has been made.
Originally Posted by MRtv
I have done a radiator only drain and fill. I do it every 1.5 to 2 years. Gets half the fluid out at a time. Then when I do it again in another 2 years the complete change has been made.
75% of the old fluid is removed if you change half the fluid twice. And that is good enough.
I have done a radiator only drain and fill. I do it every 1.5 to 2 years. Gets half the fluid out at a time. Then when I do it again in another 2 years the complete change has been made.
75% of the old fluid is removed if you change half the fluid twice. And that is good enough.
Kestas
Staff member
The OCD in me doesn't allow me to do partial drains with anything on the car.
Replenishment of the protection in a system which you haven't allowed to get dirty seems adequate given the 10 year duty cycle.
Gotta admit I do not know.
Way different than the motor oil comparison.
Gotta admit I do not know.
Way different than the motor oil comparison.
Originally Posted by Gebo
Hmmm, you got me thinking. If a fellow did it every year, which would be replacing about half every year...and I got some pH strips.....
I may be seeing a light. Bulb.
You need to test more than pH. The test strips are expensive to do a complete test.
Hmmm, you got me thinking. If a fellow did it every year, which would be replacing about half every year...and I got some pH strips.....
I may be seeing a light. Bulb.
You need to test more than pH. The test strips are expensive to do a complete test.
My approach is to just drain everything in the radiator, my vehicle will not let me drain the full system in one go, so I typically drain what I can and fill the radiator with distilled water and leave it like that for 1-2 days (while in normal use) of course I do this during an appropriate season not suggesting someone due this during a deep freeze in Montana winter tho. If I feel super up to it, I might drain it again and repeat the process the bleeder doesn't take any time to open I mean essentially 1 plastic nut on my car so it's not horrible time-consuming and I let it drain overnight.
As the saying goes "if something is worth doing, it's worth doing it right".
As the saying goes "if something is worth doing, it's worth doing it right".
Depending on the vehicle a partial drain might be all that can be done easily. On my Volkswagen there is no petcock on the radiator but the hose is easy enough to connect and disconnect. I would expect that others would be very similar.
Yes.
The G11 coolant i use lasts 3 years.
So i do a partial every year ( draining expansion tank radiator upper tank ) and put fresh coolant in
I still do a full change every 3 years, but between those i do small partial ones just to keep the inhibitors fresh.
The G11 coolant i use lasts 3 years.
So i do a partial every year ( draining expansion tank radiator upper tank ) and put fresh coolant in
I still do a full change every 3 years, but between those i do small partial ones just to keep the inhibitors fresh.
Originally Posted by ZZman
Yes. Most coolant systems these days don't seem to get nasty like they used to.
Because coolant technology has improved a lot, Old high pH, High Silicate, High phosphate, high Borate coolant tended to create all sorts of deposits.
Not even current "conventional" coolants do that anymore, as they have for example silicate stabilizer compounds that prevent it from dropping out.
Yes. Most coolant systems these days don't seem to get nasty like they used to.
Because coolant technology has improved a lot, Old high pH, High Silicate, High phosphate, high Borate coolant tended to create all sorts of deposits.
Not even current "conventional" coolants do that anymore, as they have for example silicate stabilizer compounds that prevent it from dropping out.
However if you are using a full OAT coolant i don't see the point of it, OAT inhibitors are almost non-depleting, the only thing you should test for is pH, if t's below 7-7-5, change it, ( don't be scared if it's something between 7.5-8.5 ), most modern coolant including OAT like Dexcool have a relatively low starting pH.
Originally Posted by Char Baby
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.
In addition to my statement here^^^, I am concerned about trapping air in the cooling system which some FSM's require only a D&F.
The Firebird in my signature get full flushes every 5 yrs but, it's easy, peasy, domesticeasy!
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.
In addition to my statement here^^^, I am concerned about trapping air in the cooling system which some FSM's require only a D&F.
The Firebird in my signature get full flushes every 5 yrs but, it's easy, peasy, domesticeasy!
I've done that under the advice of a very good friend of mine since the early 1980's. My cooling systems remained clean and problem free. I've done an occasional flush, once maybe twice on my 88 E-150. It still has the OE radiator and heater core. The cooling system is pristine, and I replaced 1 water pump. During the water pump replacement the cooling system was flushed. I will continue to do the same with both my Jeeps, and used the specified coolant so there is no worries with compatibility issues.
Originally Posted by Donald
Originally Posted by Gebo
Hmmm, you got me thinking. If a fellow did it every year, which would be replacing about half every year...and I got some pH strips.....
I may be seeing a light. Bulb.
You need to test more than pH. The test strips are expensive to do a complete test.
I just got the pH strips Louis Altazan recommended. At least I could keep an eye on things. I may just do a 6 month radiator drain and fill. Those engine block drains are a real pain in the booty.
Originally Posted by Gebo
Hmmm, you got me thinking. If a fellow did it every year, which would be replacing about half every year...and I got some pH strips.....
I may be seeing a light. Bulb.
You need to test more than pH. The test strips are expensive to do a complete test.
I just got the pH strips Louis Altazan recommended. At least I could keep an eye on things. I may just do a 6 month radiator drain and fill. Those engine block drains are a real pain in the booty.
Originally Posted by demarpaint
I've done that under the advice of a very good friend of mine since the early 1980's. My cooling systems remained clean and problem free. I've done an occasional flush, once maybe twice on my 88 E-150. It still has the OE radiator and heater core. The cooling system is pristine, and I replaced 1 water pump. During the water pump replacement the cooling system was flushed. I will continue to do the same with both my Jeeps, and used the specified coolant so there is no worries with compatibility issues.
Hey, my friend. Do you do it once a year? I'm thinking of doing a 6 month interval. This would really help me keeping it straight in all my vehicles. Of course I have used and will only use Toyota OEM coolant. And I would do a complete flush every timing belt/water pump change.
I've done that under the advice of a very good friend of mine since the early 1980's. My cooling systems remained clean and problem free. I've done an occasional flush, once maybe twice on my 88 E-150. It still has the OE radiator and heater core. The cooling system is pristine, and I replaced 1 water pump. During the water pump replacement the cooling system was flushed. I will continue to do the same with both my Jeeps, and used the specified coolant so there is no worries with compatibility issues.
Hey, my friend. Do you do it once a year? I'm thinking of doing a 6 month interval. This would really help me keeping it straight in all my vehicles. Of course I have used and will only use Toyota OEM coolant. And I would do a complete flush every timing belt/water pump change.