Tuesday, March 30, 2010

SV650 Radiator Coolant Flush and Change

Changing the radiator fluid or coolant is part of the regular service every liquid cooled bike needs. The SV650 manual suggests replacing the fluid every two years, but I like to change mine at the beginning of each riding season. Changing the coolant is just as easy as changing the oil. Even taking all the photos for this post, it only took me an hour.

Tools needed:

You shouldn't have to replace any bolts, screws, or washers unless they are damaged.

tools needed

Make sure the coolant you will use is compatible with your bike. For my SV650, I chose a 50/50 premixed solution specifically for a motorcycle with an aluminum engine.

fill with 50/50 aluminum safe coolant

Here are the important locations for changing the coolant on a SV650:

  1. overflow Tank Reservoir
  2. drain bolt
  3. overflow cap
  4. radiator filler neck and pressure cap
  5. safety screw on pressure cap

Location of Radiator Parts

Make sure the bike is cold. Changing the coolant is not something to do on a hot bike. I let mine sit overnight. Set a container to catch the fluid near the drain bolt. I found putting mine on a case of oil was about the right height.

pan to catch fluid

The overflow cap can be removed without lifting the tank, but I found it easier to take it on and off with the tank out of the way. Remove the cover to allow the system to breath and drain more easily.

Overflow Tank Cap

Remove the side panels with the 4mm hex key and the seat with the 6mm hex key. Lift the seat out of the way.

Remove Side Panel and Seat to Lift TankRemove Side Panel and Seat to Lift Tank

With the seat out of the way, remove these two bolts with the 4mm hex key and lift the tank.

Bolts to remove to lift tank

The tank is supported with the included tool underneath the passenger seat.

prop the tank up

Remove the overflow cap to allow the system to drain more effectively.

open the overflow cover to allow system to breath

Using the Philips screwdriver with the PH0 head to remove the safety screw. Be careful to get the right size screwdriver head as the screw is easily stripped.

Radiator Fill Cap

Slowly remove the pressure cap from the filler neck. If you hear hissing, stop and let the bike cool down further.

radiator cap removed slowly

Use the 10mm socket to remove the drain bolt and be ready to catch the stream of coolant in your container. I found rocking the bike back and forth worked well to get all of the coolant out.

Water Pump and Radiator Drain Plug

When the coolant has stopped flowing out, use a garden hose to flush the system by filling it up and letting it drain out. It took at least five times before the water coming out of the drain was clear for me.

flush with garden hose

Check the washer on the drain bolt and replace if necessary. Then replace the drain bolt and torque to 13Nm (13Nm * 0.7376 = 9.58 Ft Lbs)

replace drain bolt

Add coolant to the system slowly until it reaches the base of the filler neck. Start the bike and let it run for two to five minutes to help the air escape from the system. I found gently rocking the bike back and forth helped, especially if you only have side stand. Let the bike cool down and check the fluid level. Add more if necessary and repeat this entire step. It took me three times for this step.

fill to bottom of the filler neck

Replace the pressure cap like this to align the safety screw for easy access. Replace the overflow cap, lower the tank, and put the seat and side panels back on.

put cap on like this to make the safety screw easy to reach

Check the overflow container to make sure the coolant level is up to the full line on top. The level on mine is very difficult to see without shining a very bright light on it.

Overflow Tank



  1. Big thanks Chris -awesome work!, particularly with pics/photos as now looks like I could attempt it myself!