Well,after putting two new batteries in my '82 K2500 (6.2 ),I had a bitch of a time getting it to start ..it's been doing this for awhile now.. What it's been doing lately is after I turn on the glow plugs for about 10 seconds ,and crank it,it'll fire right up...but immediately stall unless I keep it floored,and let it rev way up (something I hate doing to any engine after a cold start)..it will usually keep running ,like its "flooded",and after 5-10 seconds or so,it'll clear itself out after belching a big cloud out of the exhaust--then I can let off the throttle gradually and it'll idle ,and everything is ok.. BUT--if it stalls after that first start,it will just crank & crank over even if I re-activate the glow pugs each time,and if I'm lucky,after a LONG cranking,it will start firing like only one or two cylinders are firing,and eventually more & more of them start firing,and it'll finally run,belch out the cloud,and clear itself out--IF the batteries aren't dying by then..(new batteries haven't yet,but I've been careful not to overheat the starter,or let the batteries get weak enough not to crank fast enough lest I kill them dead or wound them permanently).. I even resorted to taking off the air cleaner,tried spraying diesel in the intake with a pump sprayer while I cranked it remotely from under the hood,after activating the glow plugs..NADA..thing just cranked and cranked..(This has worked before for me when I ran out of fuel,to get it running long enough to self bleed). THEN I took a few pages of newspaper,crumpled it up,LIT IT ON FIRE,and put it in the intake..let the flames get going really good,then cranked it over a good 15 seconds..NOTHING..not even a fart..this tells me the glow plugs must be working,as it would most likely fire right up with a flame being sucked into the intake.. I then took off the return line hose at the injector pump,after reading the fitting in the pump has a glass check ball in it that can stick,and block the fuel flow,which will stall the engine...took out the fitting,sprayed it with carb cleaner,the glass ball is intact,clean,and the spring was free,so I dount that was causing any trouble.. Put it back together,got in the truck,activated the glow plugs,and it wanted to fire up right away,and I had to hold it floored,until the thing "cleared out" and revved up,and belched the usual cloud out of both exhaust pipes..(unburned diesel I assume,its not coolant or oil smoke)... So I have no clue WTF is wrong with this P-O-S,the electric fuel pump I put near the tank works OK,I open the bleeder on the firewall fuel filter and fuel gushes out when it is on,so I know its not too low on fuel or starving...lift pump is still in the fuel system too,its not leaking either,so I assume its OK...(and it should run on the electric pump even if it was junk).. The pink wire on the injector pump makes the solenoid inside click on and off when I pulled it off and put it back on with the key on too,so I assume that is working OK.. Once (IF) I get the truck started,it'll run all day,and fire up on one turn as long as its still "warm"--it was near 60 degrees out yesterday,so it's not like it was below freezing... I'd buy 8 new glow plugs if I thought it would cure this--but I have my doubts seeing open flames wouldn't light it off!.. After I finally got it to start I left it running about 15 minutes--now I see the oil leak has returned,it looks to be coming off the drivers side head in the rear,possibly between the head & block,or it may just be the valve cover gasket..guess I'll be dumping a quart in (at least) every time I drive it again.. SIGH....I wish I had the ability to rip this six point turd out and put a gas engine in this pig...after 17 years of it I'm about "done"...I fully expect the starter to crap out next,from all the excess cranking lately too,that'll be the third one .. The oil pan should be replaced too,but I am betting if I took it off,I'd find cracks in the block webs--or have the crank snap a week later if none are apparent,with my luck.. Anyone have any ideas WTF is wrong with it ?...could a slow drippy leak at the bottom of the fuel take let air get sucked in the fuel lines overnight ?--if so,then why does it fire right up,THEN stall,instead of having to be cranked excessively to bleed the air out?...I'm pretty much stumped.. Like I said...READY TO BURN IT!..