DS800X Rally Coolant Change & Cooling System Bleed

The official manuals differ on several points for this job: coolant capacity, drain bolt torque, thermostat cover bolt torque, the replacement mileage and the bleed method. Every value below carries its document and PDF page. Where the documents differ, all values are listed. We cannot verify which is correct.

The thermostat starts to open at 82 ± 2 deg C and is fully open at 95 deg C, with a valve lift of at least 7 mm Engine manual p. 29.

Specifications at a glance

Where the manuals give different values, each value is listed with its sources and the row is marked Sources differ. We cannot verify which value is correct.

Do not fill with running (tap) water, and do not mix coolants of different brands or specifications.

What you need

• Coolant to the specification above, in the quantity from the capacity row
• New flat washer (gasket) for the coolant drain bolt
• Torque wrench
• Drain pan, funnel and rags

Safety before starting

The engine and radiator must be cold. Remove the radiator cap only when the engine has cooled down, otherwise hot coolant can spray out and cause injury. The engine manual warns that "the coolant may inject or splash out and get you injured" Engine manual p. 25.

Coolant must not touch painted surfaces.

Procedure

1. Park and prepare

Keep the bike upright on its stand. See the centre stand technique guide. Remove the lower fairing cover.

2. Drain

Place the drain pan under the engine. The coolant drain bolt is on the right side of the engine and is fitted with a flat washer. Remove the drain bolt and washer, then remove the radiator cap and let the coolant drain. The owner's manual says all the coolant drains from this port because the system is connected.

3. Refit the drain bolt

Clean the washer seat. Fit a new flat washer and refit the drain bolt.

Tighten it to 11 N·m Engine manual p. 27 or 6 N·m Chassis manual p. 32. We cannot verify which is correct.

Wipe spilled coolant off the muffler and engine with a dry cloth.

4. Fill and bleed the radiator

The manuals describe different fill and bleed methods. We cannot verify which is correct.

• Engine workshop manual Engine manual p. 28: fill through the radiator port. Shift to neutral, start the engine and let it idle for 2-3 minutes. Open and close the throttle 3-4 times to expel air. Stop the engine, top up if necessary, then fit the radiator cap.
• Chassis workshop manual Chassis manual p. 32: fill through the radiator port with a funnel until full. Start the engine and let it idle. The level at the filler may fall, so keep filling until it stops falling, then fit the cap.
• Owner's manuals Owner's manual p. 103 Swedish owner's manual p. 109: fill the radiator until full and close the cap. The English manual says to pinch the water hose while filling to push air out. Run the engine for 30 seconds, then stop it. When the engine has cooled down, open the cap again and top up if the level has dropped. Repeat until the level no longer drops. The English manual says this may take two or more rounds.

5. Fill the expansion tank

The expansion tank sits on the lower left side of the engine. Remove its black rubber cap and fill until the level is between the upper and lower marks. Do not fill above the UPPER mark, because hot coolant expands and can overflow from the tube. Refit the rubber cap.

6. Check for leaks

Start the engine, run it at a suitably high speed and check the coolant lines for leaks. Clean the engine surface and dry it with compressed air.

Refit the lower fairing cover (9 N·m, Chassis manual p. 11).

7. Check the level later

Check the level in the expansion tank with the engine cold and the bike upright. It must be between LOWER and UPPER. If you need to top up often, the owner's manual says the cooling system has a fault and you should contact a VOGE dealer. If the expansion tank is completely empty, do not fill it yourself. Air may already be in the system and the owner's manual sends this to a dealer.

8. Disposal

Dispose of the old coolant in an environmentally responsible way.

Common pitfalls

• Filling with tap water. The owner's manual does not allow running water. The engine manual says running water may damage the engine.
• Mixing coolants. The owner's manual does not allow mixing coolants of different brands or specifications.
• Reusing the drain bolt washer. Each manual that covers this step says to fit a new one.

Other models

The DS900X uses a different engine (KEL895) with its own values. See the DS900X coolant guide and do not use its values on the DS800X Rally.

Sources

• Voge DS800X Rally Engine Service Manual (English)
• Voge DS800X Rally Chassis Service Manual (English)
• Voge DS800X Rally Owner's Manual (English)
• Voge DS800X Rally Owner's Manual (Swedish)
• DS800X Rally torque specifications, engine torque table for cross-reference

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