Washington area lenders again are raising the interest rates they charge on home mortgages and other loans and in some cases are turning away borrowers they would have accepted before.</br></br>In the past week mortgage interest rates have jumped as much as 7sths of a point. Mortgages are virtually impossible to find for less than 13 percent and many lenders are charging 14 percent or more.</br></br>Interest charges for overdraft checking and other consumer loans also are going up, although most Maryland and Virginia banks already are charging the maximum permitted by state law.</br></br>So far. bankers report, the staggering increases in the cost of borrowing show no sign of reducing consumersÛª reliance on credit.</br></br>Borrowers who qualify lor loans appear willing to pay the rates, the bankers say; only by refusing loan applications are the lenders able to cut down on borrowing.