Welcome to the forum.

He has done quite a bit, good.

It does seem as if fuel is leaking back somewhere. Replace all the fuel lines and install a new primer pump.

I don't understand the "tapped it in more" statement, the injectors are threaded.

White smoke may be an indication of oil or water in the combustion chamber. Does the white smoke smell of antifreeze? What color is the oil on the bottom of the oil cap?

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83 SD

84 CD