After reading about what a pain it is to remove the coolant drain bolt, I think I'll skip that and flush the system to clear out the engine block and heater core. I'm also switching from whatever green coolant prior owner/mechanic used when replacing water pump to Honda Type 2 coolant, so seems like a flush would be a good idea.
In the various flush guides I've read, nobody talks about draining the flush water in the engine and heater core. If I leave that water in there and add 50/50 mix, I'll end up with a coolant solution that has too much water, won't I?
I'm thinking that removing the lower rad hose will help drain enough of the flush water that I'll be close enough to the correct coolant concentration after adding the 50/50 mix.
If the front of car is on jack stands, is the bleeder bolt still the high point in the system, or can bleeding air be accomplished at the radiator cap?
Answers to the above might modify the below steps. But here's a detailed breakdown of the steps - any errors or omissions here? Thanks!
1. Start engine, set heater to max heat (fan can be off), turn off engine. This opens heater core valve.
2. Open rad cap (make sure engine/radiator are not hot)
3. Loosen rad drain plug and drain coolant
4. Pull out reserve tank and empty. Reinstall reserve tank.
5. Optional: Remove lower radiator hose to drain as much coolant as you can from engine. Reattach lower rad hose.
6. Tighten rad drain plug.
7. Fill reserve tank with distilled water. Fill radiator with distilled water. I'm guessing it's not necessary to bleed air during fill/flush with water?
8. With radiator cap off, start engine and let run until warmed up (with heater set to max heat and fan off); let radiator fan come on at least twice - fan coming on means hot coolant/water is flowing into the radiator through the upper rad hose.
9. Drain radiator, empty reserve tank. Optional: remove lower rad hose to drain engine block; reattach hose. Tighten rad drain plug.
10. Repeat steps 6 - 9 until water is clear.
11. Fill tank to Max mark with coolant (don't want to suck air into system)
12. Loosen air bleeder bolt in thermostat housing (12mm bolt); then pour coolant into radiator to bottom of filler neck.
13. Tighten the bleed bolt as soon as coolant starts to run out in a steady stream (no air bubbles)
14. With rad cap on loosely, start engine and let run until warmed up (radiator fan comes on at least twice); keep heater set to max heat, fan off.
15. If necessary, add more coolant to bring level back up to bottom of filler neck and to max mark in reserve tank.
16. Repeat steps 14-15. Tighten rad cap. Check for leaks.
In the various flush guides I've read, nobody talks about draining the flush water in the engine and heater core. If I leave that water in there and add 50/50 mix, I'll end up with a coolant solution that has too much water, won't I?
I'm thinking that removing the lower rad hose will help drain enough of the flush water that I'll be close enough to the correct coolant concentration after adding the 50/50 mix.
If the front of car is on jack stands, is the bleeder bolt still the high point in the system, or can bleeding air be accomplished at the radiator cap?
Answers to the above might modify the below steps. But here's a detailed breakdown of the steps - any errors or omissions here? Thanks!
1. Start engine, set heater to max heat (fan can be off), turn off engine. This opens heater core valve.
2. Open rad cap (make sure engine/radiator are not hot)
3. Loosen rad drain plug and drain coolant
4. Pull out reserve tank and empty. Reinstall reserve tank.
5. Optional: Remove lower radiator hose to drain as much coolant as you can from engine. Reattach lower rad hose.
6. Tighten rad drain plug.
7. Fill reserve tank with distilled water. Fill radiator with distilled water. I'm guessing it's not necessary to bleed air during fill/flush with water?
8. With radiator cap off, start engine and let run until warmed up (with heater set to max heat and fan off); let radiator fan come on at least twice - fan coming on means hot coolant/water is flowing into the radiator through the upper rad hose.
9. Drain radiator, empty reserve tank. Optional: remove lower rad hose to drain engine block; reattach hose. Tighten rad drain plug.
10. Repeat steps 6 - 9 until water is clear.
11. Fill tank to Max mark with coolant (don't want to suck air into system)
12. Loosen air bleeder bolt in thermostat housing (12mm bolt); then pour coolant into radiator to bottom of filler neck.
13. Tighten the bleed bolt as soon as coolant starts to run out in a steady stream (no air bubbles)
14. With rad cap on loosely, start engine and let run until warmed up (radiator fan comes on at least twice); keep heater set to max heat, fan off.
15. If necessary, add more coolant to bring level back up to bottom of filler neck and to max mark in reserve tank.
16. Repeat steps 14-15. Tighten rad cap. Check for leaks.
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