Author Topic: Irratic tach using F.I.E pulse generator and coil wire sending unit  (Read 3768 times)

Offline Pat Johnson

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Good afternoon Spud, Ray and i are having issues with our Autometer Sport Comp Tach, It works when you wing the motor , tach will tach up when reving the motor, it does not want to hola an idle, when motor is at idle the needle just sits around 500rpm only until you hit the throttle , hard to say where the motor is really at rpm wise, we checked all the wires and wired it to the diagram that came with our pulse generator , it seems to be all ok , wired to diagram, any sugestions that may help us, we have our last race this weekend at woodburn, weather permitting, Thanks Spud, Pat Johnson ,Tillamook.

Offline Spud Miller

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Re: Irratic tach using F.I.E pulse generator and coil wire sending unit
« Reply #1 on: September 20, 2016, 08:06:51 AM »

 If it works fine everywhere but idle, then the signal it's getting isn't quite strong enough when RPM is low. To change the signal, move the pickup to a different place.

 If it's on the coil wire, move it to the other end. Try putting on top of the magneto cap. Put it against the coil. Place it against the side of the magneto. Moving the pickup will change the signal going into the unit.

 Spud


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Offline Pat Johnson

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  • Your Track: Portland Int Rcwy, / Woodburn Raceway Ore
  • Your Vehicle: None right now< Honorary Crew Member Bay's & Rupert F/C
Re: Irratic tach using F.I.E pulse generator and coil wire sending unit
« Reply #2 on: September 20, 2016, 10:09:10 AM »
Thanks Spud we will try that, have a great day,Pat.

Offline Rusty Kramer

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Re: Irratic tach using F.I.E pulse generator and coil wire sending unit
« Reply #3 on: September 21, 2016, 03:53:14 PM »
Pat, if you have an SM5 and get that to work let us know what you did.    Since We put the SM5 on my car we lost  the tach and have not been able to get it back, and believe me I have tried.   talked to one racer with an SM5 and is using a Stack tachometer and that works for him. I will be checking into those at PRI.  My set up worked great with the an SM4 but went to heck after I had Spud hop up the Mag to a 5.