It was obvious the main starter battery had "had it" a few months back, exaserbated through lack of daily use of the vehicle (thanks to mikexgough for sourcing me a new battery
)Any road up.... New battery was fitted, engine oil and coolant was checked (levels fine) I added a cup full of fresh oil anyway just so the top end of the engine had something in there to help things along for it's first engine crank in many months
I let the glowplug relay do a full two cycles before i turned her over, accelerator fully depressed to assist pulling enough fuel through, after adding a half tank of neat diesel via jerry cans.... She fired straight up, accompanied by some diesel knock, and a few whisps of blue/grey smoke... She ran a solid 15 seconds or so before the engine died, me trying to hold her at a fast idle of 1800RPM.
Would she re-start? Did she fluff! All i got was a fast crank, so either there was no fuel getting through, or the cambelt had snapped
I attemped a few more starts giving the new battery breathers to recover on each attempt... (the new battery is a belter, it showed a constant 15-16 volts on each cold crank)
I eventually gave up, and popped over to Wheelquick for a new fuel filter, some Forte diesel additive, and a catch tank attached to a pipe so i could inject a diesel/additive concoction directly into the diesel pump to at least rule out an airlock/blockage elsewhere in the fuel system.
Upon returning we debated on how best to change the filter, attach the catch tank, add the fuel concoction etc whilst the bongo was parked a foot from my garden fence giving me almost NO access under the drivers seat.... DBO suggested attempting just one more start "just in case"
I thought it a waste of time,but tried it anyway just to shut him up Bugger me she fired straight up! I held her on a faster 2500RPM idle, whilst dave added the diesel treatment... There was a definite veg oil odour emitting from the exhaust, i reckon that was the problem after the fuel had been sat in there for many months without the bongo being started up 
I'll fill the tank up and start her up and get her up to temp every few days now till i've gotten all of the veg oil out of the tank, plus the diesel treatment should have helped clear things out by then As an added bonus, my leisure battery has now taken a charge too, but we'll just have to wait and see if it actually holds on to that charge 
My bongo lives! 
* Due to a change in my personal circumstances some months ago, the bongo went into a early winter hibernation SORNED etc
But she'll be back come spring of 2012! 
I'll dilute out the veggy with neat diesel, then more than likely use the neat diesel that's in to start the bongo up over the coming months here and there...Whatever i put in till spring next year won't get that old really, Thanks.