Diesel engine 12V 4000 G73, 16V 4000 G73. Manual - part 30

Filling coolant with pump

1.

Connect a suitable pump with a hose to the

drain valve of the engine coolant pump (ar‐

row).

2.

Release union at distributor (arrow).

3.

Open drain valve and pump coolant into en‐

gine at 0.5 bar minimum.

4.

Close venting point when coolant emerges

from the released union.

5.

Fill expansion tank until overflow edge is

reached.

6.

Close drain valve.

7.

Check proper condition of breather valve,

clean sealing faces if required.

8.

Fit breather valve and close it.

9.

Start engine (→ Page 32).

10.

After the engine has run at unloaded condi‐

tion for10 seconds, stop engine

(→ Page 35).

11.

Turn breather valve of coolant expansion

tank counterclockwise until the first stop

and allow pressure to escape.

12.

Continue to turn breather valve counter‐

clockwise and remove.

13.

Check coolant level (→ Page 116) and top

up engine coolant as required:

a) Fill in coolant via filler neck on expan‐

sion tank until the coolant level at bot‐

tom edge of filler neck remains con‐

stant.

b) Check proper condition of breather

valve, clean sealing faces if required.

c) Fit breather valve and close it.

14.

Repeat the steps from "Start engine"

(→ Step 8) until coolant no longer needs to

be topped up.

15.

Disconnect pump and hose.

Alternatively: Filling coolant

through filler neck

1.

Release union at distributor (arrow).

2.

Fill in coolant via filler neck on expansion

tank until the coolant emerges from the re‐

leased union.

3.

Tighten union (arrow).

4.

Fill expansion tank until overflow edge is

reached.

5.

Check proper condition of breather valve,

clean sealing faces if required.

6.

Fit breather valve and close it.

7.

Start engine (→ Page 32).

8.

After the engine has run at unloaded condi‐

tion for10 seconds, stop engine

(→ Page 35).

9.

Turn breather valve of coolant expansion

tank counterclockwise until the first stop

and allow pressure to escape.

10.

Turn breather valve counterclockwise and

remove.

11.

Check coolant level (→ Page 116) and top

up via filler neck if required:

a) Fill in coolant via filler neck on expan‐

sion tank until the coolant level at bot‐

tom edge of filler neck remains con‐

stant.

b) Check proper condition of breather

valve, clean sealing faces if required.

c) Fit breather valve and close it.

12.

Repeat the steps from "Start engine"

(→ Step 7) until coolant no longer needs to

be topped up.

Final steps

1.

Start the engine and operate it unloaded for some minutes.

2.

Check coolant level (→ Page 116) and top up if required.

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7.15.5 Engine coolant pump – Relief bore check

DANGER

Unguarded rotating and moving engine components.

Risk of serious injury – danger to life!

• Take special care when working on a running engine.

WARNING

Engine noise above 85 dB (A).

Risk of damage to hearing!

• Wear ear protectors.

Engine coolant pump – Relief bore

check

1.

Check relief bore for oil and coolant dis‐

charge.

2.

Shut down engine (→ Page 35) and disable

engine start, observe general safety instruc‐

tions “Maintenance and Repair”.

3.

Clean the relief bore with a wire if it is dirty.

• Permissible coolant discharge: up to 10

drops per hour;

• Permissible oil discharge: up to 5 drops

per hour.

4.

If discharge exceeds the specified limits:

Contact Service.

7.15.6 Engine coolant – Sample extraction and analysis

Preconditions

☑ MTU Fluids and Lubricants Specifications (A001061/..) are available.

Special tools, Material, Spare parts

Designation / Use

Part No.

Qty.

MTU test kit

5605892099/00

1

DANGER

Unguarded rotating and moving engine components.

Risk of serious injury – danger to life!

• Take special care when working on a running engine.

WARNING

Coolant is hot and under pressure.

Risk of injury and scalding!

• Let the engine cool down.

• Wear protective clothing, gloves, and goggles / safety mask.

WARNING

Engine noise above 85 dB (A).

Risk of damage to hearing!

• Wear ear protectors.

Engine coolant – Sample extraction

and analysis

1.

With the engine running, open drain valve

(1).

2.

Flush sample-extraction point by draining

approx. 1 liter coolant.

3.

Drain approx. 1 liter coolant into a clean

container.

4.

Close drain valve (1).

5.

Using the equipment and chemicals of the

MTU test kit, check the coolant for:

• Antifreeze concentration

• Corrosion inhibitor concentration

• pH value.

6.

For engine coolant change intervals, refer

to (→ MTU Fluids and Lubricants Specifica‐

tions).

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