Yes, there were Fords diesels made before the Powerstroke 7.3. They are the 6.9 and 7.3 IDI(indirect injection) engines. The 6.9 was made from 1982-1988. The first 7.3L was produced from 1988-1994. The original 7.3L diesel was a non-turbo charged indirect injection (IDI) engine, followed shortly after by a turbo charged version. It was very similar to the previous 6.9l IDI diesel engine, which was simply bored out for more torque. These trucks have proven well running on WVO. The weak link has been the lift pump,which regulates at 4-7psi. These pumps are not robust enough to push hot, high viscosity vegetable oil so they must be upgraded. The issue is that most robust pumps aren't regulated down to the 7PSI that the IP requires. The solution is adding an external regulator after the pump. Customers have success with Aeromotive part#13301, made form SS, aluminum and viton.
