I just traded for a ford 2000 diesel tractor, has the 3 cylinder diesel. It didn"t run when I got it, had to replace fuel tank valve, couple new fuel lines including filter, fresh oil. After bleeding injectors and spraying wd40 in intake, it started for the first time in years. It runs excellent, I let it run for hour and half, shut it off, tried to restart it, but no luck unless I sprayed wd40. What would be the cause of it needing an additive to start? Has a good battery, spins quickly over. Per previous owner, he said in the past it never needed anything to help it start. It doesnt have glow plugs and there"s no fuel leaks. Thanks for any and all help.