tach fails on 120 HP Rude

[jjboor]

I installed a teleflex tachometer on my boat to start propping my rig right. As I was running 5000 Rpms wot I installed an other prop.<br /><br />But now as I go to WOT the tach dies as soon as I go over 5000 rpms the needle just drops to zero. And as soon as I ease of the trottle and reach the 5000 rpm mark the tach starts working again.<br /><br />Can anyone please tell me what to do, where to start trouble shooting?<br />It's a 120HP V4 'Rude BE 120TLCCA connected trough the remote by an OMC cable to a new teleflex tach set to 6p (last setting on the tach)<br />thanks in advance!

 

[mannyq]

Re: tach fails on 120 HP Rude

You may need a 2K resistor between sensor and ground on tach. Check teleflex web site and they show you what to do. I had similar problem with one of my 2000 J115 dropping to 0 when it hit 3000, ended up being voltage regulator/rectifier. Check all of your electrical connection or if you have a voltmeter check the voltage when it hits 5000 to see if it gets erratic which I noticed following the motor service manual which helped to find the problem. Good luck.<br /><br /> http://www.tflx.com/obtachtrad.html