Volkswagen Workshop Service and Repair Manuals > Golf Mk5 > Power unit | 4-cylinder diesel engine (2.0 l engine, 2-valve, SDI) | Engine cooling | Parts of cooling system

Checking oil cooler for leaks

Special tools and workshop equipment required

t	Refractometer -T10007-

t	Hose clamps up to Ø 25 mm -3094-

t	Cooling system tester -V.A.G 1274-

t	Adapter for cooling system tester -V.A.G 1274/8-

t	Spring-type clip pliers -VAS 5024 A-

t	Drip tray -V.A.G 1306- or drip tray -VAS 6208-

Special tools and workshop equipment required

t	Torque wrench -V.A.G 1331-

Not illustrated

t	Expansion tank -1K0 121 407 A bzw. 6Q0 121 407 A bzw. 1J0 121 407 B-

t	Plug -191 211 343-

t	Cap -1J0 121 324-

t	Coolant hose -251 265 056-

Prerequisites:

l	Engine cold

Test procedure

–	Remove noise insulation tray.

–	Clamp supply and return lines off oil cooler using hose clamps to Ø 25 mm -VAS 3094-.

–	Loosen hose clamps -arrows- using spring type clip pliers -VAS 5024-.

Note

Collect escaping coolant with drip tray -V.A.G 1306- or drip tray -VAS 6208-.

–	Pull coolant hoses off oil cooler.

–	Slide sealing cap-5- to rear connection of oil cooler -4-.

–	Secure sealing plug-2- to breather connection of expansion tank -1-.

–	Secure coolant hose -3- to oil cooler and expansion tank.

–	Fill expansion tank up to “Max” marking.

–	Attach cooling system tester -V.A.G 1274- with cooling system tester adapter -V.A.G 1274/8- to expansion tank.

–	Use hand pump on tester to create a pressure of about 1.6 bar.

–	Watch pressure drop on pressure gauge. A pressure drop within 10 minutes is not permitted.

If pressure drops:

–	Renew oil cooler → Chapter.

Installation is carried out in the reverse order. When installing, note the following:

–	Check coolant level, if necessary replenish coolant → Chapter.

Volkswagen Workshop Service and Repair Manuals