Hello . I have a 1985 35 mercury outboard. on a 14 ft bass boat. My question is about the poles on this engine are? Serial number A153538 . My tach at WOT only goes to 3200 rpm. So I am trying to purchase a tachometer . I think the tach is my problem not engine performance since at WOT I get around 26 mph so I believe I am running more than 3200 rpm. The tach that came with the boat has no pulse switch in the back.