Financial manager is interfering your work regarding to engineering management such spare parts purchasing, stock , outsourcing jobs what best action?

Involvement of Finance should not be looked as a hurdle.

It is obligatory for finance to best assure the project remains cost effective and cost efficient.

The best way to cope with the requirements of finance is that for purchasing spare parts and stock keep record of implementation of three quotation rule, for outsourcing jobs you should be having proper justificaiton of the concept of buy and sell decisions, why you outsourced and how it is cost effective for the organization.

For any organisation operating in commercial environment, Finance management is a common element of all the functional area, whehter it be operation or maintaenance or capital work. For any activity in the above areas, the respective managers are to justify with the cost benifit analysis for the necessity to carry out the work or activity. Normally every activity should be within the budgetory allocations. The finance manager will have to accord priority as per the cashflow depending on the urgency and necessity of each activity. In the present instance, for maintaining the inventory of spares, the pereto rule of significant few and trivial many has to be resorted to. For example, regarding the spare part equirement of a Diesel Engine, your choice to keep a crank shaft should be accorded last priority because the possibility of failure of the sameis very remote, but at the same time, the bearing for the shaft should be sufficienty stocked for time bound routine maintenance. A good finance manager should see that every $ he spends should bring immediate return, and we technical managers should have domain knowlege to justify our  requrement for the benifit of the organisation.