1. Torx bits – To remove gravel guard
2. Flat Head bit (widest you can find) – To loosen drain valve/petcock
3. Right-Angled rachet driver.
4. Unlimited water source – garden hose or from tap
5. 4 Gallons Distilled water or more as required (see #15)
6. 2 Gallons Volvo Coolant (9434699-6) – 1 Gallon of the concentrate will make 8 Quarts in a 50/50 ratio.
Cooling system requires 9 quarts = 2 Gallons and 1 Quart. One bottle will not be sufficient – 1 quart short.
7. 2 clean pails
8. 1 hydraulic jack and a jack stand
9. Mechanic’s gloves/Nitrile Gloves/rubber gloves
10. Plastic funnel
11. Flat-bladed screw driver – To remove fog light grill.
Procedure:
1. Lift car on the passenger side and use a jack stand as a safety precaution.
2. Remove the gravel guard underneath the car. 7 torx screws hold it on.
3. Remove the left fog light grill.
4. Remove coolant reservoir cap. Be careful, I’ve cut my pinkie on the sheet metal every time I do this.
5. From under the car, on the passenger side, you should be able to see this. The drain valve or petcock is a red plastic knob with a drain tap protruding underneath it.
Through the fog lamp grill, you will also have access to the petcock. I prefer reaching from the front than from the bottom, because I can avoid the moving parts like the A/C compressor when I need to shut the valve off to empty the pails with the car running.
6. It is very possible the petcock must be loosened with a small right-angled rachet with a flat head bit. Find the widest one. Loosen counter-clockwise.
7. Position two pails underneath to catch the coolant as it drains out.
About 1/2 the coolant will empty out, approximately 4.5 quarts, and it will stop dripping.
If you are doing this alone, you must be sure never to let the reservoir go below the minimum while you are draining with the engine running.
8. Fill the reservoir up and drain it out a few more times. It does not have to run clear at this point. I use a garden hose because my water is filtered and treated (softened). This will only flush out the radiator. As I am also changing coolant types, it is important that I also flush out the heater core as well.
9. Close the petcock. Finger tightened lightly only until it stops dripping. Fill the reservoir up with water again. Fill up to the max level. Watch the level as the system may burp and you will need to add more water.
10. When the cooling system is full, and the petcock isn’t dripping. Start the engine and turn the heater all the way up to MAX HEAT. Turn the blowers to MAX FAN and OPEN ALL THE VENTS (Footwell, Main vents and Defrosters).
11. Go to the front and reach through the fog grill opening and open the petcock so that the coolant starts draining again. Be very careful as the AC compressor will be turning at this point and be careful not to get your fingers caught in any belts. I prefer the fog opening because you can see where your fingers are, you don’t have to crawl under the car and you are sufficiently far away from the AC compressor. You can also get back to the business of filling up the reservoir quicker from a squat than if you are lying on your back – for those of us who aren’t quite as limber anymore.
12. Fill the reservoir as the coolant drains out. NEVER let the coolant tank water level fall below the minimum.
13. As the pail fills up, you can easily reach through the fog opening, close the petcock, top up the water in the reservoir and then walk off to empty the pail as the car keeps running.
14. You can resume the fill and drain when you return without endangering the engine. The oil temperature never went above 1 1/2 units on the gauge. Keep doing this until the coolant runs clear. That means the heater core is now drained of old coolant as well. Water will be hot, but not scalding. Wear gloves to protect your hands.
Left: 100% old coolant Right: 100% water
System is clean.
15. Once the entire system is completely clear of coolant and runs clear, drain and fill with two gallons (or more) of distilled water. This is just a precautionary measure, I call this the rinse cycle. Again, I only used two gallons because the water from my garden hose is filtered and soft. If you want to be safe, use more.
16. When done, close petcock and fill up reservoir. Keep engine running.
17. Pour all of the Volvo coolant concentrate into a clean pail.
18. Pour one gallon of distilled water back into the container and swish around to get every last drop of coolant.
19. Empty contents into pail. And ensure mixture is homogeneous. Now you have 50/50 water coolant mix.
20. Use this mixture to flush the system. Open petcock, and this time pour the new coolant mixture in. Keep doing it until the blue mixture drains out. Mix more if you need to. 2 gallons of the Coolant Concentrate will yield 16 quarts of 50/50 mixture. The car holds only 9 quarts.
21. Close petcock, finger tighten. Shut engine off at this point. Then use right-angled ratchet with a flat bit. Turn petcock 1 degree more. Don’t over tighten or you risk breaking the plug.
22. Reinstall gravel guard and fog grill.
23. Occasionally check for leaks through the drainage hole with finger. Leakage from the petcock can also be detected on the ground.
Keep some coolant in the car for the next few days and check often to see if the system burped. Top up if needed.
Edit – The gravel guard does not interfere with the drainage hole underneath, so one does not need to remove it the next time this service is performed. Access through the fog light grill is sufficient to get to the petcock. This should make this job even less troublesome.