rpm tach jumps up and down at wot

[vicdur93]

my tach at wot will jump up and down from 4000 rpm to 6500 rpm . what could be the problem?<br />5.0 l u17 four winns boat

 

[Bondo]

Re: rpm tach jumps up and down at wot

Bad Connection....<br />Or,<br />Bad Tach.......

 

[steve n carol]

Re: rpm tach jumps up and down at wot

loosing speed? propshaft/prop splines? bad engine/outdrive coupler?/?<br />I know a guy who bought a rebuilt Aluminum prop.<br />Ran this for a year! The boat would plane out then down to 10 knotts @ 4000 RPM, the splines in the prop were toast. He's a funny guy! AND when he re upolstered this pontoon, (same boat), he hooked the steering up backwards, left was right, right was left ha ha. he did that for a year too!