TLDR: the tractor works again!
Of course, if you got this far then you'd like to find out how. When last I spoke of the tractor, it was parked in the shed in a state of undress while an exit fuel rail made the journey from the UK and a set of reprinted factory manuals made their journey from Missouri, USA. Curiously, both items arrived within a day of each other roughly three and a half weeks after ordering to me in rural Australia. Nice to see Covid hasn't overly impacted the USPS delivery times.
The first trick upon commencing this particular job is to assemble all the other parts required. In this case, copper crush washers, a new banjo bolt and some fuel line. The washers seal up all the connections while the banjo bolt and fittings were to build the connection between the rail and the secondary fuel filter as the original line was a soldered in part of the rail.
Next bit was to pull the old rail...making sure to cover all the diesel-y openings with some bandages.
Dummy fitting the new rail exposed the first wrinkle in this process...
... because the holes didn't line up. This explained why the links in the rail where there - to provide for 'adjustment'. However, since this rail was supposed to be for exactly this engine, I still felt a trifle aggrieved. Some careful-ish bending with plumbing pliers (along with precise application of appropriate swear words) saw four banjo bolts back in their required locations.
Reconnection of the rail to the start reservoir was a doddle while the new section to the secondary fuel filter wasn't. The new banjo fitting was a bit fiddly and I might've cut the first section of fuel line too short but it all buttoned up OK...so it was time to refit the fuel tank.
New bolts and rubber tank pads (actually Ford Falcon shock mount rubbers) and some jiggery pokery saw the tank back in place, still with sufficient clearance for the tractor hood to not bang on the fuel cap. Win! Drop 20 litres of diesel in to establish that the new fuel tap doesn't leak (another win!). Fit the new fancy braided stainless fuel line between the tap and the lifter pump...turn on the tap, fuel bowl fills...and still no leaks! Time to bleed the fuel system.
I gave the lifter pump a few strokes to push any air into either the primary filter on the other side of the engine (to be bleed off) or into the fuel bowl (where it would simply vent into the tank). Next thing I knew... there's diesel dripping on my boots.
It's at this point I should point out I was seated due to the fact that standing for any length of time with a damaged right knee (busted ACL, damaged patellar tendon) is uncomfortable. I was supposed to see an orthopaedic surgeon in the Big Smoke about it tomorrow but a rather large rain event is smashing NSW at the moment and flooding is either everywhere or imminently everywhere that I need to go. So I'm staying home...
Now where were we? Oh yeah. Diesel puddling on footwear. When I get round the tractor I find that my new connection to the secondary filter is the culprit and no amount of tightening is fixing it.
Dismantling it again demonstrates why. I've bought the wrong size crush washers. This was because I focused on the outside diameter of the washer when it is the inside diameter that is the key measurement. I had also noted that my fancy new fitting didn't have much bearing surface to work with to form a seal (because it was designed primarily for hydraulic oil) on a large flat surface.
I would have to improvise. I had some brass fittings for the 3/16" air line I was using as the fuel line (it'll be fine - at least that's what my tractor mechanic told me) and it seemed I could modify one slightly in order to braze it onto the old banjo fitting on the original rail. So I did. The banjo came off the old rail with unspeakable ease (the MAP torch nearly blew it off on its lonesome). I then had to clean the back end up with a file and drill out the last of the old solder. Next step was to drill out the new fitting where it would normally thread onto something. After that, bash the two together and then braze them to each other (protip: don't forget the flux paste like I did at first!) so they don't come apart and better still don't leak. Final job was to go back to town for the right size copper washers and some more
fuel air line.
Ugly but effective...
Bleeding was easy because all the air had already dribbled out through the leak!
The moment of truth though was hobbling up onto the tractor, pushing in the fuel control rod (opens the fuel supply to the injector pump), tweaking the throttle lever, saying a little prayer and turning the key. Damn thing fired up first go on the third turnover. No miss, no stutter. Wow.
It has moved off under its own steam leaving almost no trace of its presence for weeks in the shed. It has since been tested just yesterday by slashing the paddock and it did so with flying colours (and some smoke). And now it has returned to its usual position... plotting shenanigans with its friends in the sunshine. While I plan further work for them all...