2.25 Diesel Starts then Stops within seconds

Hi all , Hope someone can help throw some light on my problem .
1975 diesel 88'' 2.25.
The problem is that when I try to start the engine it fires and starts on the first turn but dies within seconds ,( as if it has fired on a tiny bit of fuel left ) BUT then it will not start again or even attempt to fire .( until I have primed the whole system )
There is fuel at the filter and the injectors although I have noticed a bubble in the clear pipe ( spill pipe , I think it is ) running between the injectors .
I have noticed a small leak of diesel from the ? accelerator spindle, on the injector pump , would this cause enough air to get in to cause this ?
Also when I use the primer on the fuel pump after 5 or 6 pumps there is no pressure , ? Is this right ? I thought it would build up pressure not lose it .

I hope someone can help and look forward to all the replies
Thankyou

i think you have the answer to your problem when you say it needs priming.
clear tube on spill rail is non standard and most likely cause of air getting in, i would replace with new one, plus new copper/aluminium washers 2 per injector.
have you checked the injectors with them out of cylinder head but still connected to pipes, you can then check the spray pattern.

The lift pump should keep on working pumping diesel to fill the filter from empty, however i think it can feel different depending on how it sits on the cam.
not sure how the leak from spindle may affect things, but you could clag it in grease during testing, there is also an adjustment screw for idle speed or pump timing which could cause it to stall

Thanks Steve , will give the grease around the spindle a try and change the clear pipe to a new standard one .
copper/aluminium washer is that at the end of the injector when I take it out ? or do they go on the banjo from the spill rail .
Will also check the spray pattern .

sorry for delaybeen away a few days,

the washers go either side of banjos on the spill rail, if having problems here with sealing against leaks, some PTFE tape helps

and yes if you take the injectors out you should replace both steel and copper washers

cheers steve , I will get some new washers for the banjos , looking at the old ones I think some are missing so could be a problem will get a new pipe at the same time .

I had my wife tow me across the field to try and bump start it but didnt work although it must of bleed the system as it fire first turn of the key and started on the second Only problem is 24hrs later back to none starting .... But I love my landy keeps me busy

Just an update :
Took the lift pump out today ,with a friend, and it doesn't 'quack' so I guess the diaphram is knackered , so will sort it or get a new one . Also found that a banjo bolt on the lift pump was loose .
Have taken the injector pump off to replace the spindle and O rings so we shall see how it goes when its all back together.
I hope this may also clear some of the Black smoke , fingers crossed .

UPDATE:
Well the injector pump had water in the bottom of it so things didnt look to good in there , so took it to a diesel engineer @ Minster Diesel. and he replaced the lot including the spindle . Now looks and works like new . No more body shake either or black smoke and more power , so a big bonus