Bskicrash1
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I searched the forum and didn’t see a how to. This is a relatively simple task, however, for a first timer, it is always nice seeing a how to.
I have a 2019 NC750x manual transmission. I’m draining the cooling system with just over 5k miles. I’m using Honda hp2 coolant as per the manual.
You will need 2 quarts of coolant (I use 3 quarts and I’ll explain), 1 gallon of distilled water, 5mm hex wrench, 10mm socket, 12 mm socket, JIS #2 screwdriver tip (a #2 Phillips head will work, just apply even pressure as not to strip the screw head), a funnel.
DISCLAIMER: the process described below will not remove the residual coolant that is trapped by the thermostat. There is possibly .25 quarts of coolant that will not drain out using the method below. If completely changing to a new brand and type of coolant, remove the thermostat housing to fully drain and flush the old coolant.
PROCEED AT YOUR OWN RISK. I am no way responsible for your actions.
1. Remove the lower cowl. Use the 5mm hex wrench for this. (I didn’t take a photo of this step as I forgot).
2. Locate the 10mm bolt under the motorcycle just rearward of the header pipe. This bolt has a copper crush washer, so be careful not to lose this when draining. Mine stuck to the engine then dropped into the catch pan and I ended up fishing it out.
3. The cap is held secure by a #2 JIS screw. This is to prevent the cap being spun off. Carefully remove this screw and then remove the cap. The coolant will now flow fast.
4. Locate the bracket that holds the horn assembly and coolant overflow tank. Use a 10 mm wrench to remove the reservoir from the bracket.
5. Use a 12 mm wrench or socket to then loosen the two bolts holding the bracket to the frame. I do not remove the bolts, I just loosen them enough so I can move the reservoir from behind the frame and drain the contents. (Caution, the oxygen sensor wire runs through a tab on the frame and around the reservoir. Use caution separating the wire before moving the reservoir.
6. Carefully tip the reservoir to drain the coolant.
7. Use a funnel and pour distilled water into the coolant reservoir and flush the old coolant residue out. Reinstall the reservoir in reverse order. Pay attention to the two rubber hoses as they are routed through tabs on the tabs on the reservoir.
8. Use a funnel in the radiator and pour approximately 1/2 gallon of distilled water into the system. If you look, the color of the fluid draining from the drain bolt will change to clear.
9. Then reinstall the drain bolt hand tight. I pour approximately 3/4 a quart of the new coolant into the system.
10. Then remove the coolant drain bolt and watch the color of the fluid go from clear to the blue of the Honda coolant. This is to ensure I do not have extra water in the system.
11. Then reinstall the drain bolt.
12. Fill the radiator and the coolant reservoir. This takes about 1.25 quarts of fluid.
13. Reinstall the radiator cap.
14. Start the motorcycle and let it heat up to operating temperature. I wait until the radiator fan turns on to ensure the thermostat opens and lets any air trapped in the system pass to the radiator.
15. Once the motorcycle is completely cooled. Open the radiator cap and top off with coolant. Also, check the reservoir and make sure the coolant level is between the low and high mark. If not, add coolant to the proper level.
16. Reinstall the lower cowl.
When I started this process, it was 20F. The frost on the motorcycle is visible.
Enjoy!
I have a 2019 NC750x manual transmission. I’m draining the cooling system with just over 5k miles. I’m using Honda hp2 coolant as per the manual.
You will need 2 quarts of coolant (I use 3 quarts and I’ll explain), 1 gallon of distilled water, 5mm hex wrench, 10mm socket, 12 mm socket, JIS #2 screwdriver tip (a #2 Phillips head will work, just apply even pressure as not to strip the screw head), a funnel.
DISCLAIMER: the process described below will not remove the residual coolant that is trapped by the thermostat. There is possibly .25 quarts of coolant that will not drain out using the method below. If completely changing to a new brand and type of coolant, remove the thermostat housing to fully drain and flush the old coolant.
PROCEED AT YOUR OWN RISK. I am no way responsible for your actions.
1. Remove the lower cowl. Use the 5mm hex wrench for this. (I didn’t take a photo of this step as I forgot).
2. Locate the 10mm bolt under the motorcycle just rearward of the header pipe. This bolt has a copper crush washer, so be careful not to lose this when draining. Mine stuck to the engine then dropped into the catch pan and I ended up fishing it out.
3. The cap is held secure by a #2 JIS screw. This is to prevent the cap being spun off. Carefully remove this screw and then remove the cap. The coolant will now flow fast.
4. Locate the bracket that holds the horn assembly and coolant overflow tank. Use a 10 mm wrench to remove the reservoir from the bracket.
5. Use a 12 mm wrench or socket to then loosen the two bolts holding the bracket to the frame. I do not remove the bolts, I just loosen them enough so I can move the reservoir from behind the frame and drain the contents. (Caution, the oxygen sensor wire runs through a tab on the frame and around the reservoir. Use caution separating the wire before moving the reservoir.
6. Carefully tip the reservoir to drain the coolant.
7. Use a funnel and pour distilled water into the coolant reservoir and flush the old coolant residue out. Reinstall the reservoir in reverse order. Pay attention to the two rubber hoses as they are routed through tabs on the tabs on the reservoir.
8. Use a funnel in the radiator and pour approximately 1/2 gallon of distilled water into the system. If you look, the color of the fluid draining from the drain bolt will change to clear.
9. Then reinstall the drain bolt hand tight. I pour approximately 3/4 a quart of the new coolant into the system.
10. Then remove the coolant drain bolt and watch the color of the fluid go from clear to the blue of the Honda coolant. This is to ensure I do not have extra water in the system.
11. Then reinstall the drain bolt.
12. Fill the radiator and the coolant reservoir. This takes about 1.25 quarts of fluid.
13. Reinstall the radiator cap.
14. Start the motorcycle and let it heat up to operating temperature. I wait until the radiator fan turns on to ensure the thermostat opens and lets any air trapped in the system pass to the radiator.
15. Once the motorcycle is completely cooled. Open the radiator cap and top off with coolant. Also, check the reservoir and make sure the coolant level is between the low and high mark. If not, add coolant to the proper level.
16. Reinstall the lower cowl.
When I started this process, it was 20F. The frost on the motorcycle is visible.
Enjoy!
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