300SDL Misses After FI Pump Work

[Spook74]

I continue to have an issue on my SDL after trying to fix delivery valve leakage. (I had inadvertently pulled the lower valve sleeves and know that I had installed them misaligned.)

I have since received a used FI pump, and may need to swap it in, but before I did, I started the car, (after installing a new battery, which helped tremendously!) The car would run, but it blew black smoke and missed. Loosening the injector lines one at a time indicated that #3 did not affect rpm, so I focused on that one.

I pulled its delivery valve, and also the lower pump sleeve under the top metering piston/sleeve, the one with the alignment slot in it, and put a dab of grease on one edge of it and reinstalled it. Then I took a magnet and tried to turn it, and sure enough, I could walk it around with the magnet when it was seated all the way down. (The dab of grease was on top, opposite the slot, so I could know when it was aligned properly and see if it moved when I tried to turn it with the magnet.)

Next, I unscrewed the pump side plate. With a mirror, I could see the alignment pins in their bores, each with a peen mark to keep it in place. The #3 (and #4) pins were pushed right up to the peening, while the others were recessed about 1/8". Aha! These two pins had been pushed back into their bores when I had reinstalled the sleeves earlier with the slots not aligned with their pins! (#4 sleeve may have happened to have been aligned properly, even without pin engagement?)

I ensured that the sleeve slots were aligned with the pins and then tapped the pins deeper back into their bores with a small pin punch. I again tried to turn the sleeves with the magnet, and they would not turn. Sounded like I had it, so I reassembled everything and restarted the engine. It still misses! Dang.

Back to loosening the injector lines, and checking which cylinder was acting up. This time, it was #6! Hmmm... Time to pull it too. I gave it the same exercise as the others, and rebuilt and restarted. Still no joy. And now, I cannot find one injector line that does not cause rpm drop when I loosen it! Time for a break.

Anybody have any other ideas to try before I jump into pulling the injection pump and swapping in the used one? Looking over that manual section, it does not look like an easy job, and lots of special tools are called out. Maybe time to farm out the job? :-(

Tomorrow, I intend to stick each injector line into a jar for a measured time to see if one is still weak. I'm also checking for any air leaks into the fuel lines. Any other ideas?

Thanks, Guys!
Gerry
87 300SDL, feeling poorly...