Today was the first time I changed the filter on my 2015 1.6 CRDi, as up until now it's been dealer serviced. However, the cost of the 'essentials' service is now excessive for what they do.
There are a few YouTube videos showing how to do it, but here are a few tips based on what I did today. The battery has to be disconnected and removed, the ECU unplugged and removed by undoing the 3 screws which hold the mounting bracket, to gain access to the filter. Unplug the electrical connectors, the fuel lines have a blue clip on either side which have to be pressed in whilst tugging the line off the filter. It's made more difficult because there's very little room to get your finger between the lines to press the clips on the inner side. I removed the line on the rear side by pressing in the clip I could see with a screwdriver, and the other side with my finger tip. With the line out of the way, it's easier to get a finger in behind the front line to press the clip in on the rear ride of it.
After undoing the 3 nuts which hold the filter bracket on, the filter cab be extricated out of the engine bay, unclipping the fuel lines support bracket from the side of the filter. With the filter out of the car, undo the screw which attaches the filter manifold to the outer case, loosen off the clamp screws which clamp the outer case around the filter cartridge, and unclip the cable from the water sensor in the base of the filter, that strap it to the outer case. The filter can then be pulled out of the case. Have a clean jar ready to collect diesel fuel still in the filter.
First loosen off the filter cartridge from the top manifold. The cartridge on my car was really tight, so I took a sheet of coarse sandpaper, folded it in half, wrapped it around the filter and clamped it in my portable workbench. That stopped it slipping round whilst I rotated the manifold around to loosen it off. Once it was loosened off, I took it out of the workbench, and unscrewed the water sensor at the bottom by hand, holding it over the jar to collect the fuel that will drain out of it. Then unscrew the filter from the manifold and tip fuel out of the top into the jar. The filter was a Hyundai/Kia part but also had the Mahle part number exactly as I had bought.
Fitting the new filter is like changing an oil filter. Lubricate the rubber gasket with a smear of oil, screw it in until it makes contact, then tighten it up another half-turn by hand. Screw the water sensor into the bottom, using the new sealing ring supplied with the new filter. Insert the filter cartridge into the outer case, fit the screw which secures the upper manifold to the case, tighten up the clamp screws, and clip the sensor cable back where it was. Before fitting back into the car, I laid the filter on it's side with the fuel line pipes pointing upwards. With a big 300ml syringe I bought, and a short length of PVC tube, I injected fresh diesel into one pipe until it started to ooze out of the other pipe, thereby filling the new filter with fuel. It takes about 500ml of fuel to fill the filter up.
After fitting the filter assembly back into the car, re-connect the fuel lines and wiring plugs, refit the ECU and plug the wiring harnesses back in, refit the battery. As I pre-filled the filter with fuel, I only had to crank the engine for 7 or 8 seconds before the engine fired up. It's worth getting a big syringe so you can pre-fill the filter, I use the same syringe for draining old brake fluid out of the reservoir when changing the brake fluid, cleaning out the syringe between jobs. I'll also try the syringe to squirt fresh oil into the gearbox, as that is due for replacement. Hopefully there are no leaks, but it's not easy to spot if there are any because it's buried away behind the ECU. I have to change the oil so when I'm under the car I'll see if there's any leaks from below.
