Coolant Change

My Additional Notes : Yanmar 4JH4-TE Diesel 75 hp Turbo

Change Every 2 years using Long Life Coolant (Pink)

Requirements:

· Large clean bucket for mixing coolant (7.25 litres)

· Coolant Long Life Type A Caltex, 4 litres (Pink) and demineralised/distilled water, 4 litres OR

Nulon Coolant Premix Pink (6yr or 350,000k's) 8 litres

· Measuring jug

· Funnel

· Thin tubing ¼” x 2 metres clear for drain cocks

· Collection bucket with cord attached for coolant

· Spanners small open spanners:

Port mid forward and starboard drain cock 12ml

Port Aft 10ml

· Containers for old coolant

Procedure to Empty:

• Ascertain location of 3 drain cocks, see picture at end. Port mid forward, Port aft, Starboard mid low. Each drain cock has small nipple for attaching tubing with nut head under.

• Attach one end of tubing to Port mid drain cock, other end in bucket. Loosen screw. No coolant will leak from screw. Allow to drain completely. When coolant stops flowing tighten screw. Remove tube and repeat procedure for Port aft, finishing with Starboard mid low.

• Remove coolant recovery tank and empty.

• Measure how much coolant has been removed as this is the amount of new coolant to be returned. In this case approximately 7 litres will be removed.

Procedure to Refill:

• Mix coolant and demineralised water in clean bucket. Use the correct amount of coolant concentrate based on manufacturers recommendation as this will vary depending on ambient temperature. In this case 50% ratio used.

• Fill coolant tank with remainder of coolant. Pour slowly to avoid air lock in tank. It is important to return the same amount of coolant. If this is not the case you may have an airlock.

• Fill recovery tank to mid level with coolant/water mix and reattach.

• Start engine, run for 10 minutes and check coolant level in recovery tank, top up recovery tank if necessary. Repeat procedure. NB Do not remove cap on engine coolant tank as steam may escape causing injury.

Procedure to Remove Airlock:

• Remove filler cap

• Bleed air by attaching tubing to port mid drain cock, other end in bucket. Loosen screw. Let coolant flow for a few seconds. If air is trapped, an obvious flow of air with minimal coolant should be evident. Repeat for remaining drain cocks if necessary. Ensure all screws have been tightened.

• Finish filling tank with the remaining coolant, including that which you drained in the bleeding process.

• Replace filler cap

Above: Coolant Reservoir