IAM TRYING TO FIND AN IMPELLER FOR THIS MOTOR,THE MODEL# GG18736 SER# 16X819460 ANY INFORMATION WOULD BE TRULY APRECEATED ,DOES ANY BODY KNOW IF OLDER JOHNSON PART'S FIT,OR EVEN THE YEAR OF THIS MOTOR ,I HAVE HAD IT FOR OVER 25 YEARS AND I BOUGHT IT SECOND HAND BUT THIS IS THE FIST BIG PROBLEM...