Section 236(5) in The Navy (Pay And Allowances) Regulations, 1966
(5)Before sanctioning an advance, the sanctioning authority shall satisfy itself that the conveyance has not already been purchased and paid for and if the conveyance has been paid for in part, the sanctioning authority shall restrict the advance to the minimum amount required to meet the balance of the price of the conveyance:Provided that where an officer purchases a conveyance after applying for the advance and arranges to pay for it by raising a temporary loan, he may be permitted to draw the advance, subject to other conditions being satisfied if the conveyance was purchased within 3 months of applying for an advance.