I haven't even started the engine in a few months due to a leak I found on one of the fuel injector return lines. It was just a slow drip, but I don't need a puddle of diesel oil on the driveway. Yesterday I decided to fix this issue.
I opened the engine cover inside the bus so I could work on the hoses from injectors 4, 5, and 6. The tube labeled "Pipe B" connects all six return hoses to a common hose that goes back to the fuel tank.
"Hose A" shows the part I replaced on all six injectors. The old hoses were brittle and cracked and even though only one was actively leaking, I figured they all should be replaced at once.
"Hose C" is the same type of hose and so I replaced it as well. The trick was getting everything reconnected once the new hose was attached to each injector. Since the common pipe is non-flexible, I had to carefully feed the barbed ends into each little hose all at the same time. I started with the No. 1 fitting and then guided each subsequent fitting into the hoses until they were all inserted and lined up. Then I used a prybar to carefully push the pipe into each hose a little at a time. I had pre-positioned all the hose clamps so all I had to do was squeeze them and slide them into place over the hose barbs.
This job took about three hours over two days (I got rained out midway through the first day). I wasn't especially difficult, although I'm a little sore from bending over to work on the front half of the engine. The rear half was simple as I sat on the floor of the interior and worked in relative comfort. It was also really nice having the quick-detach driver's seat so I didn't have to crawl around a chair fixed to the floor next to the engine cover.
After I finished I tried the engine and it started right up. I think I last ran the engine about three months ago, maybe less. I can't believe how reliably it starts every time I've tried (with the exception of the times I've forgotten to disable the fuel cutoff ... oops).
I also cleaned the engine cover while it was out of the bus (please ignore the rusty bolt heads):