Checking Cooling System For Water Leaks

Checking Cooling System For Water Leaks

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.





Checking pressure relief valve in cap:
Detach rubber (1) from hand pump.
Attach special tool 17 0 007/17 0 008.





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.





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.