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How To:- Radiator / Coolant replacement

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Tools required (items in bold are only required on a radiator change)

Metric socket set (10mm, 12mm,13mm),
Ring spanner 19mm.
Large water pump pliers.
Large vice grip pliers.
cross point Screwdriver.
flat blade Screwdriver.
Axle Stands.
Trolley Jack.
Spirit level.

Materials required

2 large 5ltr bottles of Toyota Forlife red coolant (or 5 litres of advanced Halfords anti-freeze and 5 litres of top up water)
4x 40mm Jubilee clips.
Small tube of Copper grease.
Rubber gloves (like you doctor wears!) or a big bar of soap!

Optional extra

Fine mesh to act as a radiator guard.

Important safety information

Always ensure your car is supported safely on a pair of axle stands when working underneath your vehicle. Never rely on your jack alone.

Never open your radiator pressure cap when the engine is hot. Always allow time for your engine coolant to fully cool to avoid the risk of being burnt.

1- Arm yourself with your rubber gloves. You'll save yourself a lot of soap later on!

2- Remove the radiator pressure cap and set the interior heater control to HOT.

3- Remove the radiator upper trim panel. This is secured via several easily accessible plastic fasteners that require unscrewing, before they can be popped free. To withdraw the trim you will need to pull the leading edge of the rubber bonnet seal off.

Tip If the plastic fasteners spin without undoing, apply gentle pressure under the screw head with a small flat blade screwdriver, whilst unscrewing. If this does not work, you can pull the clip off with pliers and replace if with a new one from your Toyota parts department.

4- Remove the spare wheel and the large black trim panel the spare rests in. This is held by several trim fasteners. Pressing the centre of the fastener in with a blunt implement will unlock the clip.

5- Jack up the front of the vehicle and support the vehicle on Axle Stands. More information in jacking points can be found here

6- Remove the front plastic under-tray by undoing the bolts with a 10mm socket. The fasteners on the leading edge of the tray are likely to snap due to corrosion. Fear not, as these are designed to be easily replaced if they snap. If you are only performing a coolant change, you will only need to remove the drivers side section.

7-Remove the centre 2 sections of plastic under-tray by unbolting the bolts with a 10mm socket. There are also 2 push fit trim clips holding 1 of the trays in place. These simply pull free.

8- Unscrew and fully remove the radiator drain valve on the lower drivers side of the radiator. Position your bucket ready to collect the coolant as it drains from the radiator.

9- Unscrew the 2 drain plugs from the main coolant pipes underneath the vehicle. A washing up bowl positioned underneath is great for collecting the old coolant.

10- Raise the rear of the vehicle using your trolley jack positioned under the centre of the rear subframe. With the vehicle level, all remaining coolant can be expelled from the radiator and the under-body pipes.

11- The engine block drain plug is located next to the thermostat housing. I decided not to drain this point. The choice is yours!

12- Lower the rear of the vehicle and replace the under-body pipe drain plugs, ensuring they are fully tightened.

If you are not replacing the radiator, proceed to step 25

13- Unbolt the 2 upper radiator support brackets and pull them upwards to free them from the radiator. Be careful with the drivers side bracket as this has a hidden cable clip that holds the cable that releases the bonnet catch.

14- Undo and remove the 2 bolts that hold the bonnet catch and carefully move the catch out of harms way. There is no need to disconnect it?s cable.

15- Carefully disconnect the electrical connectors for the electric cooling fan and the radiator temperature sensor. Be careful not to strain the wiring as the plugs have a locking mechanism that can be released with a small flat blade Screwdriver.

16- Removal of the cooling fan at this stage will make it easier to detach the radiator hoses. The fan is held by 3 bolts. The 2 lower bolts are highly likely to snap due to corrosion, but fear not as the snapped bolts will end up in your old radiator, so who cares! Withdraw the fan from below.

17- The radiator hoses are held in place by nasty spring style clips. Using a pair of vice grips, clamp the clip into the open position and carefully slide the clips on the bulkhead end of the hose off in the direction of the radiator.

18- The hoses can now be detached from the bulkhead ends. As they are very tight fitting and positioned in a tight corner, use a pair of pump pliers to wiggle the hose off its fitting.

Tip If the hoses still cant be loosened, pour boiling water slowly onto the hose. The heat will expand and soften the rubber hose allowing easy removal with the pump pliers.

19- You will now be able to withdraw the radiator. You can remove it from the top or bottom (I found the bottom easier with the 2 hoses still engaged onto the radiator). You need to raise the radiator about 1 inch to detach it from its rubber lower mount before removal from below can occur. This can be done by gently prizing the base of the radiator upwards from below with a flat blade screwdriver.

20- With the radiator free from the vehicle, you can remove the 2 radiator hoses with ease (again using boiling water if required) and remove the fan temperature sensor with a 19mm ring spanner. When fitting the hoses to the new radiator, I decided to bin the nasty spring clips in favour of good old fashioned jubilee clips. Push the hoses into place, but don't fit a jubilee at this point. Install the fan temperature sensor and tighten fully.

21- Position the new radiator into place and twist the 2 hoses so that they are lined up correctly to the bulkhead fittings. Slide 2 jubilee clips over each hose, and then push both hoses onto the bulkhead fitting. Make sure the hoses are correctly positioned, then tighten the jubilee clips.

22- Check that the radiator lower drain plug is fitted and fully tightened. Reconnect the fan temperature sensor plug and push hard to ensure its lock engages.

23- Replace the 2 upper radiator mounts as well as the bonnet catch. Don?t forget the bonnet catch cable clips into the hidden cable clip on the driver side mount.

Tip Apply a small amount of copper grease to all bolts when refitting. This will ease any removal required on a later occasion.

24- Working from underneath, refit the cooling fan and reconnect it?s electrical connection, ensuring the plug lock engages.

25- Using the 2 service hoses supplied with the car (in the tool kit), attach one end of each hose to the heater control unit air bleed valve and radiator upper bleed valve. Suspend the other end of the hoses from the bonnet using string. Ensure the hose ends are at least 30cm higher than the height of the coolant filler neck. If you don?t have the pipes, purchase 1 meter of 8mm diameter clear pipe

26- Raise the rear of the vehicle using your Trolley Jack until the car is level. This is really important to allow air to escape freely. I used a spirit level on the engine side cover to ensure I had the car in the correct position.

27- Open the valve on both the heater unit and upper radiator bleed valves. Both need to be opened by 3 full turns.

28- Pop your Funnel into the coolant filler neck and slowly pour the new coolant into the engine. By gently pouring the coolant in slowly, you are allow air to be expelled with the minimum of fuss.

Tip Measure the amount of coolant drained from the vehicle. By keeping track of the amount of new coolant installed, you will have a good idea how well the bleeding process is working.

29- Keep adding coolant until the level reaches the filler neck. Raise and lower the height of the rear of the vehicle with your Trolley Jack. This helps trapped pockets of air to be expelled from the cooling system. Return the vehicle to dead level and continue adding coolant. I found I could get to within half a litre of the amount of drained coolant using this method. I found that the fluid level visible in the service pipes was higher on the heater than the radiator.

30- Close both bleed valves and replace the radiator cap. Only twist the cap half way i.e. do not tighten it fully.

31- Start the engine and run at a fast idle of around 2500rpm for 2 minutes. Turn off the engine and then remove the pressure cap and reopen both bleed valves 3 full turns.

32- Top up the coolant until it reaches the top of the filler neck. Check the service pipes. Both should have the same fluid level that matches the height of the filler neck. If they do not, air is still present. Repeat steps 30 and 31

Tip I found that tapping the tip of the radiator can bring air from the top of the radiator, as can gently squeezing the radiator hoses. Check that the service hoses are free from obstruction.

32- The bleed valves can now be closed fully and the service hoses removed. Replace the radiator cap fully.

33- Now check all connectors, hose clips and bleed valves to ensure the are secure before replacing the trims.

34- Refit all under-body trims. Make sure any panels that overlap are positioned so that the panel nearest the front of the vehicle is overlapping the panel nearest the rear of the vehicle. This ensures air passing under the vehicle does not crack the panel at speed. Apply a small amount of copper grease to all metal fasteners to aid removal at a later date.

35- Refit the spare wheel trim and radiator upper trim.

36- Run the engine until the electric cooling fan activates and check for signs of leakage.

37- Allow the engine to cool fully, then remove the radiator cap and recheck the coolant level. This should be just below the top of the filler neck. Top up as required. Also top up the expansion bottle it the coolant level is not between the 'min' and 'max' markers

38- Keep a close eye on the coolant level over the next 20-30 miles of driving to make sure there are no leaks or released air pockets.

Peter Jones.

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