I have a 1990 Colombia Parcar I got from a friend. Got it running but the Walbro carb leaks gas terribly and throttle spring is Mia on top of the carbs throttle plate, so can only operate throttle by hand. The only number on the side carb doesnt come up anywhere on the net. I would like to order a replacement carburator but can only find LMB230 replacement carbs that only work upto 1986 in the description. They look very similar including the throttle and oil pump linkage plate, except that in the intake side my carburetor is round and not flanged. On the engine side of the carb the flange bolts are 44mm apart. Any ideas? TIA