This is in relevance to an app running an extended OCI and the 'potential' variables that changing the coolant/anti-freeze out(including a rinse phase) may have on oil life during interval. I was wondering if there would be any harm in changing out the coolant now and going another 8,000 miles on this current fill(5 months or so)?
Some of the reasons for asking:
What are the risks of running the engine too hot while doing a 'flush' the following way(more of a rinse phase trying to mix the new coolant with remnants of the Prestone, and drain that as well)...
Drain radiator with engine cold(?)
Re-insert plug into radiator after draining
Fill via thermostat location(top of radiator) with engine running(heater on high/vent) using either Honda's HG-II pre-mix or Amsoil's coolant(diluted to a 50/50 mixture with purified/distilled water)
Allow engine to idle to "operating" temp(trans cooling fan coming on at least once, perhaps twice?), then drain and refill to the right 'eye' test via the radiator fill neck.
The concern is that I want to get away from Prestone 50/50 in the yellow bottle marketed as "Extended Life"; since I want the 'best' for the old Honda Civic(overkill at this point, perhaps but I'd rather be thorough and learn to do a coolant change myself etc), unless I'm mistaken and the Prestone that I'm currently using is the best for this app?
My final question and concern for temp is related to the reservoir being filled while doing the 'rinse' phase. Should it be empty(still connected) or have it filled with fresh of the new 'preferred' coolant in the event it wants to induce some to aid in cooling and prevent it from sucking air?
Thanks and yes I am still learning.
Some of the reasons for asking:
What are the risks of running the engine too hot while doing a 'flush' the following way(more of a rinse phase trying to mix the new coolant with remnants of the Prestone, and drain that as well)...
Drain radiator with engine cold(?)
Re-insert plug into radiator after draining
Fill via thermostat location(top of radiator) with engine running(heater on high/vent) using either Honda's HG-II pre-mix or Amsoil's coolant(diluted to a 50/50 mixture with purified/distilled water)
Allow engine to idle to "operating" temp(trans cooling fan coming on at least once, perhaps twice?), then drain and refill to the right 'eye' test via the radiator fill neck.
The concern is that I want to get away from Prestone 50/50 in the yellow bottle marketed as "Extended Life"; since I want the 'best' for the old Honda Civic(overkill at this point, perhaps but I'd rather be thorough and learn to do a coolant change myself etc), unless I'm mistaken and the Prestone that I'm currently using is the best for this app?
My final question and concern for temp is related to the reservoir being filled while doing the 'rinse' phase. Should it be empty(still connected) or have it filled with fresh of the new 'preferred' coolant in the event it wants to induce some to aid in cooling and prevent it from sucking air?
Thanks and yes I am still learning.

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