Fresh fluids

In my last Our Cars article, you read about me servicing my wife’s 2015 Ford Kuga 1.5 Ecoboost. What I neglected to tell you only struck me about two weeks later after I serviced it. My wife started the engine up one day and was greeted by “Oil Change Required” warning message. It wasn’t present when I carried out the service as I had effectively serviced it early and had completely forgotten that it would need its service warning reset. To do this, get in the car and make sure all doors and windows are shut. Press the stop-start button to switch the ignition on which will then display the service warning. Next, simply press both the brake and throttle pedals and hold them down, the dash should then change the message to read, “Service: Oil reset in prog.” After about 20 seconds, it will read “Service: Oil reset complete” and you are good for another year or 12,500 miles, whichever comes first.

Anyway, I promised regular service would be resumed with more tales about my 2013 BMW 535i. As it’s ten-years-old and I have owned it for the last seven

of those years, I know it’s never had a coolant change nor has the oil in its differential been changed either. I did these fluid changes at the same time as its annual oil service, I’ll not bore you about that again. But I make no apologies for stressing the importance of annual oil changes.

Rear axle

The differential oil change looked quite straight forward despite the cost-saving measure of not installing a drain plug and only having a fill plug, necessitating the purchase of a pump that can both suck the old fluid out and squeeze in the new fluid. To get the correct amount of oil in the diff, the car needs to be level so that the oil flows out of the fill plug when it has reached the correct level. What didn’t help was that I wasn’t 100% sure of the volume of oil I needed as it depends on the specification of the differential which I couldn’t confirm. It’s the difference between 800ml and 900ml so I knew 1 litre of febi SAE 75W-85

GL-5 oil would be sufficient. Once jacked up and level, it’s straightforward to do, crack open the filler plug with a 14mm Allen key bit and be prepared to catch any dribbles. Now to test my home-made adapter for draining the oil, this is a ‘J’ shaped piece of 10mm dia copper pipe. A small adjustment was necessary, and the pipe was now sat on the bottom of the inside of the differential casing to get as much possible of the old oil out. Refilling

The old diff oil was easily sucked out of the diff thanks to the pump and homemade adapter, look at the colour of 60,000-mile diff oil!

was much simpler with a short length of hose on the pump. Once the new oil dribbled out of the fill plug, I quickly installed a new lubricated filler plug and torqued it to 60Nm. All that is left is the biggie, the automatic transmission fluid change along with its filter.

Changing the coolant

There is no drain point on the radiator nor the block, so it’s a case of removing a hose at the lowest point in the system to drain it down. With the system devoid of coolant, I take the opportunity to carry out a few other jobs which needed doing. You can look forward to that in a forthcoming feature. With the cooling system plumbed back together, I test it for integrity by pulling a vacuum from the voids. With the vacuum holding, the system is in good health, and I then use the vacuum to my advantage and use it to fill the system with new fresh febi coolant. The vacuum in the cooling system sucks the coolant out of the container and into the expansion tank without spilling a drop. Once 4.7 litres has made its way into the system the vacuum feed line is changed to a container of water to top up the system to its 9.3 litre capacity. One last party trick is to fire up the electric water pump to bleed the system. If your diagnostic tool can’t operate the pump, BMW have a hidden way to activate the pump. To do this... 1) Switch on the ignition.

2) Switch on low beam headlight.

3) Set heater to max heat and have fan at

lowest speed.

4) On cars with the driving mode switch,

make sure it’s not in ECO mode. 5) Press and hold the throttle to the carpet for 10 seconds without starting the engine.

You should now hear the pump whirr and see a jet of coolant appearing in the top of the open expansion tank.

Fresh febi fluids – 5W-30 Longlife Plus engine oil, SAE 75W-85 GL-5 gear oil, G11 (G48) coolant – all to BMW specs and an oil and air filter.

A 1.5 litre pump with tubing was bought for less than £20 and the copper pipe was lying around my garage, the shape of which allows it to be fed in via the fill plug and touch the bottom of the diff casing.

The vacuum in the cooling system is then used to suck in the new febi coolant straight from the bottle.

A clean of the pump and new febi diff oil was carefully poured into the pump body and slowly squeezed into the diff casing.

After creating the vacuum, the hoses collapse, in what looks an alarming way, but that’s the effect of the air pressure squashing the hoses once voided of air.

The electric water pump is activated to circulate (bleed) the new coolant around the engine, you can see the jet from the small hose at the bottom left of the picture.