hi
aint old engines cool

it aint electrical
if u spin the engine over on the starter , does white smoke come out of the exhaust , ? which would show fuel is getting thru , full throttle
i'd loosen all three injector pipes ,( 2 full turns no need to remove) at the top , injector end , spin it over, if it squirts out of them all , pulsing diesel then fuel is there
b t w if its bubbling then air still in system , keep cranking
then poss injectors are at foult ( but all three failing at the same time ?un lightly ) dirty fuel shouldn't (shouldn't lol ) ever be able to reach injectors but i guess it would soon block them if it did .
easy to test a injector ( a very crude methed i know ) once removed just re fit it to the high pressure pipe , tighten it pionting some were safe ,(not youre face and wear goggles) spin engine , watch the spray . be very careful tho the very high pressure jet will punture skin ect. -- stand clear . no spray - its blocked send it away to be serviced ( send all three )
the fuel should be a very fine mist , leaving the injector tip dry , if it dribbling or a jet of fuel then its worn out
might have to crank the engine a while to purge the air .
prob £20 + a injector for a re build , if they are old ,prob are, then money well spent , if only to rule that out .
u can buy nozzles to fit ur self but i wouldn't .
even if only 1 injector working i think it would fire and try to run ?
gd luck m8
keep us posted
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