17 00 009 Checking cooling system for water leaks

Special tools required:

WARNING: Danger of scalding!
Only perform this work after engine has cooled down.

Checking pressure drop in cooling system:

Remove cap on expansion tank. Attach special tool 17 0 002 / 17 0 005.

Build up gauge pressure of 1.5 bar, wait approx. 2 minutes.

Cooling system is impervious to leaks if pressure drop is max. 0.1 bar.

Fig 1: Checking Cooling System For Water Leaks

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Checking pressure relief valve in cap:

Detach rubber (1) from hand pump.

Attach special tool 17 0 007 / 17 0 008.

Fig 2: Attaching Special Tool

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Screw cap (1) onto special tool.

Build up pressure with special tool (hand pump) 17 0 002; observe pressure gauge to ascertain when opening pressure is achieved.

Compare opening pressure of pressure relief valve.

Fig 3: Screwing Cap Onto Special Tool

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Checking vacuum valve in cap

Screw cap (1) onto special tool 17 0 007 and connect to vacuum hose of vacuum pump.

Sourcing reference: BMW Parts Service.

Feed vacuum pump with battery positive voltage.

Slowly apply partial vacuum to cap.

Compare opening pressure of vacuum valve.

Fig 4: Checking Vacuum Valve In Cap

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