Is it a good practice to fill the radiator following a complete drain, with distilled water and coolant instead of tap water? My motorcycle calls for distilled water and another factor is the tap water in this area is hard. The cost is minimal.

Congratulations on the 10 year post anniversary......the help given by the members is invaluable.....My thanks to those who keep it going.

 

From the service manual:

If the procedure below is not followed a low or high coolant level condition and/or vehicle damage could result.


Park the vehicle on a level surface.
Remove the surge tank cap:
Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Place a drain pan under the drain ****.
Open the radiator drain ****.
Allow the cooling system to drain completely.
Inspect the engine coolant for the following:
Discolored -- follow the flush procedure below.
Normal in appearance -- continue with the next step.

Notice
When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.



Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.


Close the radiator drain ****. Tighten
Tighten the radiator drain **** to 2 N·m (18 lb in).

Fill the cooling system through the surge tank.
Fill the cooling system with a 50/50 mixture of DEX-COOL® coolant and deionized water.
Start the engine.
Allow the engine to idle for 1 minute.
Install surge tank cap.
Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant temperature reaches 99°C (210°F).
Shut off the engine.
Remove the surge tank cap.
Start the engine.
Allow the engine to Idle for 1 minute. Fill the surge tank to 12.7 mm (0.5 in) above the COLD FULL mark on the surge tank.
Install the surge tank cap.
Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant reaches 99°C (210°F).
Shut off the engine.
Remove the surge tank cap.
Top off the coolant as necessary, 12.7 mm (0.5 in) above FULL COLD mark on the surge tank.
Rinse away any excess coolant from the engine and the engine compartment.
Inspect the concentration of the engine coolant.
Install the surge tank cap.

 

I used distilled water when I did mine yesterday.

One of the primary reasons coolant needs to be changed is that the sacrificial chemicals in new coolant (the ones that inhibit corrosion by offering themselves up instead of the alloys of the engine) are depleted over time. If you use tap water (particularly hard water), the coolant must use some fraction of the sacrificial chemicals to eliminate the tap water's contaminants, hastening the time at which depletion is complete and the coolant should be changed again. I don't have any data as to how much the tap water minerals deplete the coolant (for all I know, it may be trivial), but as cheap and readily available as distilled water is, I saw no reason to have unnecessary depletion by tap water.

 

No need to check the manual on this one. Where the heck are you going to buy deionized water???

Actually, Prestone used to sell deionized water in gallon jugs (at Walmart no less), but it must not have been a great seller, and I am not sure they even make it anymore. You can get deionized water if you buy the pre-mixed versions.
Otherwise, distilled water is probably as close as you will get to pure water without a lot of minerals floating around.
Even the additives in coolant cannot completely get rid of the minerals in a lot of tap water. The minerals may not attack the metal, but they can form solid deposits in the radiator that will eventually block some of the core tubes.
The last time I replaced a water heater in my house, I pulled the relief valve and looked at the wall of the heater. I was amazed at how thick the crust was on the wall just from the dirt and minerals dissolved in the water, not to mention fluoride and other chemicals that are added on purpose.

The only problem with buying the pre-mixed antifreeze is that you will pay as much for the water as the antifreeze. The last time I checked, it cost $1 less, but you are only getting 50% antifreeze, so I still bought 100% antifreeze and got a gallon of distilled water for $.50.

 

Funny right there,

I left my tank cap off cold and when the thermostat opened, I lost my new coolant in a geizer equal to old faithful...

 

50/50 Distilled and Dex-Cool

 

i buy the premixed dexcool - makes its much easier, pour and go

 

I was at Walmart this morning so I read the label on the Prestone pre-mixed coolant, and it said they use de-mineralized water, not de-ionized water.
I would think that distilled water would qualify as de-mineralized, so I will stay with the distilled water.

Based on comments above, I may go back and check for deionized water in the drinking water section of the grocery section.

 

I normally just leave the cap on loosly until I see the coolant level drop in the tank. Then I add coolant to the right level, put the cap on completely, and drive the car until it reaches full operating temperature. The next morning when it cools down, I re-check the level. It usually only takes one cycle.

 

Through the 2001 model year the manual just said to use clean drinking water. After that it said to use de-ionized water. However, you would have to be careful with de-ionized water since it can be quite corrosive depending on how pure it is. In its purest form it isn't recommended for human consumption. Of course once its mixed with the Dex Cool it isn't pure anymore but getting it and handling it before you mix it could be interesting.

This is what I found on the net:
Ultrapure water has a very low conductivity and is a very aggressive solvent which will attack stainless steels and even glass. Really pure water is actually difficult to work with and store--it readily absorbs gasses and requires Teflon coated containers under inert gases.

Bill

 

good info here!!!