@BluFalcon So the idea of installing inline filter by the firewall beside the coolant reservoir is moot, because in my head there is lots of line there and plenty of space. In reality, there is not even enough length of straight line to fit the dang filter by this expansion coolant tank and there is a bracket that further limits the space. I had to install it in similar location as in Whitbread's guide. Even then, it is crucial that you do not cut off too much from original return line, because line starts to bend on both ends and you need to leave enough straight horizontal line to fit onto filter nipple adequately before it starts to bend up. What I did is I disconnected the blue clip itself first, then I pulled return line from the metal tubing. I lowered the line down toward serpentine belt into a cup and drained diesel fuel from there. Makes it cleaner when you make the cut. I removed the blue clip completely off, pulled the rubber counterweight donut (whatever you call it), and spent 15 minutes trying to pull off the dang pipe sock all the way off (I succeded, but will need to go to Church this weekend for my tongue). If you don't pull the sock off, you will have to make a cut where pipe sock sits in the portion of it; and if you just cut the pipe sock, it will unravel like a homemade sweater. Before you start pulling the sock off, mark with a marker where you want it to end so you have enough free line for a clip/hose clamp. When you remove the sock, cut the marked line, BUT KEEP IN TIGHT IN YOUR HAND! Have a friend to keep other side tight. Then use a flame (I used a lighter for grill) to melt the edges you cut. Once you melt the diameter of the cut, it will not unravel anymore. Do it for the other side of the cut. Now you have 2 socks. Now proceed to cut the actual fuel line that is sockless and exposed. I made a cut RIGHT in the middle of that stretch, and then I realized that I could only trim maybe half inch from either side, and actually I may have trimmed too much from one end and it makes it harder to pull the hose over filter nipple since line starts to curve. By the way, here are the PEX cutters I used for fuel lines, very nice and makes clean cuts. And when your plumbing fails, you have a tool to cut pex-B pipe! Can find that in your local Lowes in blue or HD in orange, Sharkbite brand:
Anyways, once you are happy with trimming your line, and I was not, because in perfect world, you need to trim the length of the line that is length of entire in line filter housing. If you did so, you would leave ZERO straight section and have it cut right on bends. To counteract the fitting problem (trying to fit the longer stretch now with filter), I routed the circular section of pipe above the other lines instead of as it was running below before. You will see it on photo below (route it before you attach filter, easier that way). That helps to offset the firewall side of the line a little backwards. Then put the longer part of the sock back on to protect you lines from rubbing against each other. You can put the other smaller side of sock on the other line to protect it where it may rub against intake line. Anywhere lines can rub, that sock will be protective. Even after routing round line above others and adjacent to metal bracket that houses DPF sensor (I think), there is still too much line, but you can route in in such a way that it is almost OEM. Put the donut back, because it helps keep separation from input and return lines. Tighten all clamps, reconnect the line and blue clip, reposition socks where you need them, and you're done. I used the rubber double donut that originally connected two lines where filter is now oriented up and down to hold lines together, I think it looks good. All fits well.
You see on photo above how I routed that circular return line ABOVE coolant line. In original installation, that line runs BELOW the coolant line. It just buys maybe extra half inch, which helps. So, it is important that you put the sock back on since these lines will rub with vibration and vibration rubs holes in lines.
Here is overall overview of entire system installed on CKRA. Orient IN side of filter toward the front of car, OUT side of filter toward the cabin, since the flow goes from engine toward back into tank.
I want to say this was fun, but I would be lying. It was not hard, but it was not that much fun. I find it more exciting when things connect like factory. When I look at this, it looks like a hack job. I know I did my best to make it look nice and be functional, but it ruins otherwise perfect factory look. But for sake of possibly saving $8k in repairs and labor, I can live with a little hack job appearance. And if the car ever needs to go on sale, I have brand new replacement lines that I can just swap over and make it OEM again.
P.S. One last thing, after I took photos, I moved those spring clips that surround the plastic sensor a little toward the front. That way, the sharp edge of it will not rub a hole in return line if they decide to get closer together. Small things to consider to avoid trouble in the long run. Prime with VCDS (though not necessary since this is return to tank line) and start engine. Check for leaks. And I take no liability or responsibility if you choose to follow any of my guides. I do hack jobs and totally not a mechanic. Thanks for listening!
