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Keep your cool

Checking the coolant level before each ride

Warning: DO NOT remove the radiator pressure cap to add coolant. Topping up is done via the coolant reservoir tank filler. DO NOT leave open containers of coolant about, as it is poisonous.

1    Check the coolant level when the engine is cold and with the bike upright.
2    Refer to your manual or owner's handbook to locate the coolant reservoir. The level lines, usually an F (full) and L (low) are often difficult to see and you may need to wipe road dirt off the reservoir to see them clearly.
3    Make sure you have a supply of coolant available. Either use a pre-mix coolant purchased from a motorcycle dealer or mix 50% distilled or soft water with 50% corrosion inhibited ethylene glycol antifreeze. It is important that antifreeze is used in the system all year round, and not just in the winter. Do not top the system up using only water, as the system will become too diluted.
4    The coolant level should lie between the
F and L level lines marked on the reservoir
(see illustration 1).
5    If the coolant level is on or below the L line, remove the reservoir filler cap (see illustration 2). Top the reservoir up with the recommended coolant mixture almost to the F level line, using a suitable funnel if required (see illustration 3). Fit the cap securely.
6    The coolant shouldn’t require repeated topping up. If the coolant level falls steadily, check the system for external leaks. If no leaks are found and the level continues to fall, it is recommended that the system is pressure tested.

Periodic checks of the cooling system

Warning: The engine must be cool before beginning this procedure.

1    The coolant hoses will deteriorate with age – examine each hose along its length, looking for cracks, abrasions and other damage. Squeeze each hose at various points. They should feel firm, yet pliable, and return to their original shape when released. If they are cracked or hard, fit new ones. Check that the hose clips are tightened securely (see illustration 4).
2    Check around the bottom of the water pump
(see illustration 5). If the pump cover is leaking, check that the bolts are tight – if they are, remove the cover and replace the seal with a new one. If the pump-to-crankcase joint is leaking, remove the pump and replace the body O-ring and seal with new ones. If coolant is leaking from the drain hole on the underside of the pump, the internal mechanical seal has failed and should be replaced with a new one (see illustration 6).
3    Check the radiator for leaks and other damage
(see illustration 7). Leaks in the radiator leave
tell-tale scale deposits or coolant stains on the outside of the core below the leak. If leaks are noted, remove the radiator and have it repaired by a specialist. Do not use a liquid leak stopping compound to try to repair leaks.
4    Check the radiator fins for mud, dirt and insects, which may impede the flow of air through the radiator. If the fins are dirty, remove the radiator and clean it using water or low pressure compressed air directed through the fins from the back. If the fins are bent or distorted, straighten them carefully with a screwdriver. If airflow is restricted by bent or damaged fins over more than 20% of the radiator's surface area, replace the radiator with a new one.
5    Remove the pressure cap from the radiator filler neck by turning it anti-clockwise until it reaches the stop (see illustration 8). Now press down on the cap and continue turning it until it can be removed.
Warning: Do not remove the pressure cap when the engine is hot. It is good practice to cover the cap with a heavy cloth and turn the cap slowly anti-clockwise. If you hear a hissing sound (indicating that there is still pressure in the system), wait until it stops, then continue turning the cap until it can be removed.
6    Check the condition of the coolant in the system.
If it is rust-coloured or if accumulations of scale are visible, drain, flush and refill the system with new coolant (see below). Check the antifreeze content of the coolant with an antifreeze hydrometer
(see illustration 9). If the system has not been topped up with the correct coolant mixture the coolant will be too weak to offer adequate protection. If the hydrometer indicates a weak mixture, drain, flush and refill the system.
7    Check the cap seal for cracks and other damage.
If in doubt about the pressure cap’s condition, have it tested by a Kawasaki dealer or fit a new one. To fit the cap, align the tabs with the cut-outs in the filler neck (see illustration 10). Press down on the cap and turn it clockwise until it is tight.
8    Start the engine and let it reach normal operating temperature, then check that there are no leaks. As the coolant temperature increases, the electric fan (mounted on the back of the radiator) should come on automatically and the temperature should begin to drop. If it does not check the fan motor and fan circuit carefully. Also, if necessary, check the operation of the thermostat.
9    If the coolant level is consistently low, and no evidence of leaks can be found, have the entire system pressure checked by a Kawasaki dealer.

Changing the coolant

Warning: Allow the engine to cool completely before performing this maintenance operation. Also, don't allow antifreeze to come into contact with your skin or the painted surfaces of the motorcycle. Rinse off spills immediately with plenty of water. Antifreeze is highly toxic if ingested. Never leave antifreeze lying around in an open container or in puddles on the floor; children and pets are attracted by its sweet smell and may drink it. Check with local authorities (councils) about disposing of antifreeze. Many communities have collection centres which will see that antifreeze is disposed of safely. Antifreeze is also combustible, so don't store it near open flames.

1    Make sure the engine is cold. Support the motorcycle so that it is upright. Remove bodywork as necessary to access the water pump, radiator and coolant reservoir.
2    Remove the pressure cap from the radiator.
3    Position a container which will hold around two litres beneath the water pump. Unscrew the drain bolt and allow the coolant to completely drain from the system (see illustrations 11 and 12).
4    Remove the bolts securing the coolant reservoir to the frame, then remove the filler cap and tip the coolant out of the reservoir into the container
(see illustration 13). Alternatively disconnect the overflow hose from the radiator filler neck and allow the coolant to drain from the hose without disturbing the reservoir mountings (see illustration 14). Rinse the inside of the reservoir with clean water.
5    Rinse all old coolant from the system with clean tap water by inserting a hose in the radiator filler neck. Allow the water to run through the system until it is clear and flows out cleanly.
6    Install the drain bolt using a new sealing washer.
7    Prepare enough coolant to refill the system. Either use a pre-mix coolant purchased from a motorcycle dealer or mix 50% distilled or soft water with 50% corrosion inhibited ethylene glycol anti-freeze.
8    Install the reservoir and/or the overflow hose, then fill it up to the F level line with coolant and fit the cap.
9    Fill the radiator to the base of the filler neck with the coolant (see illustration 15), pouring it in slowly to minimise the amount of air entering the system. Squeeze the coolant hoses to expel any trapped air and check that there are no leaks, then fit the pressure cap.
10    Start the engine and allow it to reach normal operating temperature. Let it run until the
cooling fan comes on, then stop the engine and let it cool.
11    Check the coolant level in the reservoir and top up if necessary.

Flushing the cooling system

If when draining the old coolant you notice that the system is contaminated or that the radiator is extremely corroded, the system can be cleaned in situ using a flushing compound.

1    Choose a flushing compound which is compatible with aluminium components, and follow the manufacturer's instructions carefully.
2    Install the drain bolt in the water pump. (It’s OK to use the old sealing washer for this purpose.) Fill the cooling system with clean water mixed with the flushing compound. Fit the pressure cap.
3    Make sure the coolant reservoir is bolted in place and its overflow hose connected at each end. Fill the reservoir to the F level line with clean water and fit the cap.
4    Start the engine and allow it to reach normal operating temperature. Let it run for about 10 minutes, then stop the engine and let it cool.
5    Remove the pressure cap from the radiator filler neck by turning it anti-clockwise until it reaches the stop. Now press down on the cap and continue turning it until it can be removed.

Warning: Do not remove the pressure cap when the engine is hot. It is good practice to cover the cap with a heavy cloth and turn the cap slowly anti-clockwise. If you hear a hissing sound (indicating that there is still pressure in the system), wait until it stops, then continue turning the cap until it can be removed.

6    Unscrew the drain bolt on the water pump and allow the water and flushing compound to completely drain from the system.
7    Drain the water and flushing compound from the reservoir and fill the reservoir with clean water.
8    Fit the drain bolt, then fill the system with clean water only and fit the pressure cap. Run the engine for a few minutes, then allow it to cool, before draining the water from the system and reservoir.
9    Now refill the system and reservoir with fresh coolant as described in the coolant change procedure. Use a new sealing washer on the coolant drain bolt this time.

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