Diesel engine 12V 4000 G73, 16V 4000 G73. Manual - part 32

7.16.4 Charge-air coolant – Filling

Preconditions

☑ Engine is stopped and starting disabled.
☑ MTU Fluids and Lubricants Specifications (A001061/..) are available.

Special tools, Material, Spare parts

Designation / Use

Part No.

Qty.

Charge-air coolant

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.

CAUTION

Cold coolant in hot engine can cause thermal stress.

Formation of cracks in components!

• Fill / top up coolant only into cold engine.

Preparatory steps

1.

Turn breather valve of filler neck on coolant

expansion tank counterclockwise to first

stop and allow pressure to escape.

2.

Continue to turn breather valve counter‐

clockwise and remove.

Filling with charge-air coolant using

pump

1.

Connect a suitable pump with a hose to the

drain valve (arrow).

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.

Set breather valve onto filler neck and close

it.

9.

Start engine (→ Page 32).

10.

After the engine has run at unloaded condi‐

tion for 10 seconds, stop engine

(→ Page 35).

11.

Turn breather valve of filler neck on coolant

expansion tank counterclockwise to first

stop and allow pressure to escape.

12.

Continue to turn breather valve counter‐

clockwise and remove.

13.

Check coolant level (→ Page 126) and top

up 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.

14.

Repeat the steps from "Start engine"

(→ Step 8) until coolant is no longer needed

to be topped up.

15.

Disconnect pump and hose.

TIM-ID: 0000014848 - 002

Alternatively: Filling coolant

through filler neck

1.

Open venting point at distributor (arrow).

2.

Fill in coolant in expansion tank until the

coolant level at top edge of filler neck re‐

mains constant.

3.

Close venting point when coolant emerges.

4.

Check proper condition of breather valve,

clean sealing faces if required.

5.

Set breather valve onto filler neck and close

until first stop is reached.

6.

Start engine (→ Page 32).

7.

After the engine has run at unloaded condi‐

tion for 10 seconds, stop engine

(→ Page 35).

8.

Turn breather valve counterclockwise and

remove.

9.

Check coolant level (→ Page 126) and top

up if required:

a) Repeat the steps from "Start engine"

(→ Step 6) until coolant is no longer

needed to be topped up.

b) Check proper condition of breather

valve, clean sealing faces if required.

c) Set breather valve onto filler neck and

close it.

Final steps

1.

Start the engine and operate it at unloaded condition for some minutes.

2.

Check coolant level (→ Page 126) and top up if required.

7.16.5 Charge-air 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.

Charge-air 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.

TIM-ID: 0000000943 - 002