Coolant change
06-25-2007
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Coolant change
Does the engine block need to be drained also or will a simple drain of the radiator be sufficient? Do you also have to remove and drain the overflow resovoir?
06-25-2007
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Re: Coolant change
I would remove and drain the reservoir, it takes five minutes to do so and that way you can also shoot it with Simple Green and really get it cleaned out.
As far as the block goes, I just bought one of those $6 flush kits by Prestone and used that. You cut the heater hose, put the tee adapter in, hook up a garden hose and follow the instructions. Works like a charm and flushes out the whole system, to include the heater core and block. Just make sure you take out as much hose as the tee adapter is large (about an inch) so the heater hose fits right after you add the tee. Plus this way you now have an air bleed point in your system when you go to refill it.
As far as the block goes, I just bought one of those $6 flush kits by Prestone and used that. You cut the heater hose, put the tee adapter in, hook up a garden hose and follow the instructions. Works like a charm and flushes out the whole system, to include the heater core and block. Just make sure you take out as much hose as the tee adapter is large (about an inch) so the heater hose fits right after you add the tee. Plus this way you now have an air bleed point in your system when you go to refill it.
06-26-2007
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Re: Coolant change
Drain the block....
Some of the crazy **** people on bobistheoilguy.com seem to swear by getting a few gallons of distilled H2O, putting that into the system, running the engine for maybe a minute to circulate but not long enough to get the water uncomfortably hot when you drain it, then drain and fill with the real coolant. Via osmosis, theoretically the distilled H2O will pull deposits and such out of the coolant passages... YMMV.
Have fun... As far as those prestone powerflush kits, I don't know how much I trust them. It just seems to me cutting a hole in my coolant hose to shove a plastic chinese part in with an equally cheap plastic valve tee is asking for a bit of trouble. I suppose I'd be cool replacing the radiator hose after using the flush kit, though. My uncle owns a radiator shop. i shall ask him.
The shop manual says:
1. Start the engine. Set the heater temperature control dial to maximum heat, then turn off the ignition switch. Make sure the engine and radiator are cool to the touch.
2. Make sure you have the anti-theft code for the radio, then write down the frequencies for the radio's preset buttons.
3. Remove the battery.
4. Remove the radiator cap.
5. Loosen the drain plug (A) and drain the coolant. (Drain plug is under the bottom of the radiator...duh)
6. Remove the drain bolt (A) from the rear of the cylinder block. (Pic of bolt, it is right by the oil filter, torque to 58 lb/ft You'll want a new washer, too.)
7. After the coolant has drained, apply liquid gasket to the drain bolt threads, then reinstall the bolt with a new washer and tighten it securely.
8. Tighten the radiator drain plug securely.
9. Remove, drain and reinstall the reservoir. Fill the tank to the MAX mark (A) with genuine Honda All Season Antifreeze/Coolant Type 2.
1. Start the engine. Set the heater temperature control dial to maximum heat, then turn off the ignition switch. Make sure the engine and radiator are cool to the touch.
2. Make sure you have the anti-theft code for the radio, then write down the frequencies for the radio's preset buttons.
3. Remove the battery.
4. Remove the radiator cap.
5. Loosen the drain plug (A) and drain the coolant. (Drain plug is under the bottom of the radiator...duh)
6. Remove the drain bolt (A) from the rear of the cylinder block. (Pic of bolt, it is right by the oil filter, torque to 58 lb/ft You'll want a new washer, too.)
7. After the coolant has drained, apply liquid gasket to the drain bolt threads, then reinstall the bolt with a new washer and tighten it securely.
8. Tighten the radiator drain plug securely.
9. Remove, drain and reinstall the reservoir. Fill the tank to the MAX mark (A) with genuine Honda All Season Antifreeze/Coolant Type 2.
10. Pour genuine Honda All Season Antifreeze/Coolant Type 2 into the radiator up to the base of the filler neck.
NOTE:
* Always use genuine Honda All Season Antifreeze/Coolant Type 2. Using a non-Honda coolant can result in corrosion, causing the cooling system to malfunction or fail.
* Genuine Honda All Season Antifreeze/Coolant Type 2 is a mixture of 50% antifreeze and 50% water. Pre-mixing is not required.
Engine Coolant Refill Capacity [including the reservoir capacity of 0.4 l (0.4 US qt, 0.4 lmp qt)]:
M/T:
4.0 l (4.2 US qt, 3.5 lmp qt)
A/T, HONDA MULTI MATIC:
3.9 l (4.1 US qt, 3.4 lmp qt)
11. Install the radiator cap loosely.
12. Install the battery.
13. Start the engine and let it run until it warms up (the radiator fan comes on at least twice).
14. Turn off the engine. Check the level in the radiator and add genuine Honda All Season Antifreeze/Coolant Type 2 if needed.
15. Put the radiator cap on tightly, then run the engine again and check for leaks.
16. Enter the anti-theft code for the radio, then enter the customer's radio station presets.
NOTE:
* Always use genuine Honda All Season Antifreeze/Coolant Type 2. Using a non-Honda coolant can result in corrosion, causing the cooling system to malfunction or fail.
* Genuine Honda All Season Antifreeze/Coolant Type 2 is a mixture of 50% antifreeze and 50% water. Pre-mixing is not required.
Engine Coolant Refill Capacity [including the reservoir capacity of 0.4 l (0.4 US qt, 0.4 lmp qt)]:
M/T:
4.0 l (4.2 US qt, 3.5 lmp qt)
A/T, HONDA MULTI MATIC:
3.9 l (4.1 US qt, 3.4 lmp qt)
11. Install the radiator cap loosely.
12. Install the battery.
13. Start the engine and let it run until it warms up (the radiator fan comes on at least twice).
14. Turn off the engine. Check the level in the radiator and add genuine Honda All Season Antifreeze/Coolant Type 2 if needed.
15. Put the radiator cap on tightly, then run the engine again and check for leaks.
16. Enter the anti-theft code for the radio, then enter the customer's radio station presets.
06-26-2007
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i personally would not use the flush kits only for the reason you have to run hose water through the system. regular tap water carries lots of minerals and deposits and this will cause corrosion and build-up in the radiator, etc. for this reason, i usually do a drain and refill (of the radiator only) about once a year or so. the mineral build-up may be minimal and occur over time, however, i'm just **** like that.
04-06-2008
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I didn't remove my battery when I changed my coolant and now the car idles very rough and almost stalls when idling. Any ideas why this happens? the car ran fine before the coolant change.
03 civic si
03 civic si
04-06-2008
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More details, please. Did you at least disconnect the battery cables? For the si, do you need to take the battery out to get at the reserve tank? How much coolant did you put in? did you flush with distilled H2O first? Did you drain the block? Did you re-train the ecu? Did you have the front of the car on jacks so you didn't get air in the system? did you open the heater vents up by turing to full hot for a while?
If the only thing you did period was to change the coolant, try re-training the ecu and making sure there are no air bubbles in the block or heater core. Did you wait until the block was cool before draining the coolant?
More detail will get you a better answer.
04-07-2008
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Thx for the reply.
No, battery does not block reserve tank and no, I didn't disconnect the battery cables.
Yes the block was cool before I drained it and all I did was open the valve at the bottom (03 Si) and let it drain out. The car was up a blocks. I then opened the radiator cover to let the rest drain out, put the plug back in at the bottom and then re-filled with new coolant.
Didn't open heater vents either. Didn't drain block or reserve.
Now sometimes it runs fine and other times it won't idle and runs rough. Do you think there is air in the system? If so, how do I bleed it to get the air out?
What is the ecu and what do you mean by re-training it?
thank you.
No, battery does not block reserve tank and no, I didn't disconnect the battery cables.
Yes the block was cool before I drained it and all I did was open the valve at the bottom (03 Si) and let it drain out. The car was up a blocks. I then opened the radiator cover to let the rest drain out, put the plug back in at the bottom and then re-filled with new coolant.
Didn't open heater vents either. Didn't drain block or reserve.
Now sometimes it runs fine and other times it won't idle and runs rough. Do you think there is air in the system? If so, how do I bleed it to get the air out?
What is the ecu and what do you mean by re-training it?
thank you.
04-08-2008
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Bumping threads this quickly will get people mad at you. Just F.Y.I.
The E.C.U. stands for Engine Control Unit, or the car's central computer. These cars aren't as simple as they used to be. With Fuel Injection and Variable Valve Timing, it's almost impossible to do extreme modifications without a major in Computer Science.
I'd go to the local Auto Parts store and buy a Chilton or Haynes service manual, those things are worth their weight in gold for DIY'ers.
If you're driving the USDM '03 Si, then you might wander on over to ephatch.com, they're more model-specific and will have more information on the EP3 than this site.
The E.C.U. stands for Engine Control Unit, or the car's central computer. These cars aren't as simple as they used to be. With Fuel Injection and Variable Valve Timing, it's almost impossible to do extreme modifications without a major in Computer Science.
I'd go to the local Auto Parts store and buy a Chilton or Haynes service manual, those things are worth their weight in gold for DIY'ers.
If you're driving the USDM '03 Si, then you might wander on over to ephatch.com, they're more model-specific and will have more information on the EP3 than this site.
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