Cast that can far away into the farthest corner of your garage!
PLEASE PLEASE stay away from starter fluids!!
745 TurboGreasel says it should be `installed in my trash can`.
I say `being with a nice lady of your choice, Vi@gra is not needed AND it should never* be used at all` .
Replace the fuel filter immediately (dont forget to FIND&remove that old O-ring!), try running the car from a jar (CLEAN diesel) to see if it can handle it. Check for air in fuel and bleed system *completely if necessary, check your glow plugs! Many other things to blame but these came into my mind first. Deal with 1 issue at a time/first; I wouldn`t touch the valves yet!
About the motor oil consumption: ``1 qt in 500 miles (or less)`` is a LOT i think! Check for oil in your coolant (at expansion tank).
Lucky find, a nice Volvo, hopefully a survivor. You were constantly flushing your cylinder walls with that cr@p.
(((Just to make thinking about solving your hard-start/no-start problem much easier, let`s assume for now that 1, your injection pump does work perfectly and 2, there IS compression in your engine (although low compr itself shouldn`t cause you hard starting) AND 3, your glow plugs (or at least 4 of them) work correctly +the relay (doublecheck YOUR manual-toggle-glow setup)...
then...
-especially IF you have/had *any diesel fuel leak/leaks anywhere-, I`d say
you have air introduced into the fuel system... so now you have to get clean fuel into the system, a brand new (good quality) filter, maybe a hand-pump (or electric fuel pump) prior* the filter and
bleed the whole thing as a start. Get a strong battery too. While bleeding and cranking a lot, you can/should disconnect the glow plugs just to be on the safe side. You`ll only need them later when clean fuel does get everywhere where it needs to get. You can use diesel purge Lubro Molly instead of diesel fuel just to boost things up a bit. Watch out with dirty fuel, also, do not let anything get into the fuel supply. )))
You are very lucky, many Volvo Dieselers live around you!! Professional help is coming very soon! I hope you don`t mind that I just shared my `first opinion` on your problem.
PS. Check again those home-made Mercedes-to-Volvo injector lines.
PS2. Did you ever take out injectors? (sensitive parts, proper installation needed there; that can be another source of your dieseling troubles)
PS3. If someone PRO from here the d24t forum could check the timing...
PS4. It`s scary (even to talk about it) but you can check your belts. The timing belt in the front is under a cover. Inspect it. It should not be off or extremely loose. The rear belt at the firewall should NOT be too tight and should have no teeth missing. Confirm that.