My fiance just bought this trolling motor at a yard sale. It is model #217-590240 and serial #28-244259. It works and goes forward and reverse but there is no speed control. Does anyone out there know anything about these and if there is a way to repair this? Maybe a manual or electrical diagram. I've been doing a little searching and I think it was made by ESKA or possibly Force if it is 1987 or after. Any help would be greatly appreciated. Thank you in advance