rectifier / tacho jhonston 135hp 1975

[flips]

wired up tacho that came with this motor will not rev past 1300rpm, Old two wire job red to sender/ black to ground. Put new telflix tacho in wired to instrutions send to grey wire /ground to earth in control box ign to power source to bat, will power back to zero but will not pick up revs, have switch set to 6p <br />all i can see in telflex trouble shooting is rectifier could be bad. tested wires at tacho end and have 3-5 volts at 1500 rpm where do we go from here as this is driving me crazy<br /><br />F lips

 

[redmopar]

Re: rectifier / tacho jhonston 135hp 1975

My 1979 johnson 115 was originally set to 6p and works fine now. Grey wire to tach. Had a problem before. The tach would come on when ignition was turned on, fall to zero and never move. The accesory plug behing the control box was all corroded. Cleaned it and a lil corrosion-x and it works like a champ. Also added a zip-tie around the connector boot to prevent any further moisture infultration. Try the 4p setting if this dosen't work, it won't hurt the tach.

 

[flips]

Re: rectifier / tacho jhonston 135hp 1975

Thanks for the reply redmopar<br />fixed it ,IT WAS RECTIFIER<br />dealer here wanted $150.00 got one for $90.00<br />thanks Flips