3GM Tachometer sending unit

[Richard Bryer]

Has anyone found a substitute for the Yanmar tachometer sending unit on the 3GM? A new one is $200 here in Canada. I am sure the Yannie is usedin some Kubota and John Deere equipment- anyone ever used a unit from one of these or any other ideas?

Thanks

 

[Marc14857]

Is it a sending unit issue or is it the tach. Most of the newer (Approx 2002) tachs get their signal off of the alternator. I replaced my Yanmar alternator with a VDO alternator at about half the cost. Turns out that VDO makes the Yanmar tachometer for my boat which has the 4AE engine. Everything fit perfectly including the wiring harness.

 

[Richard Bryer]

The 3GMs use an induction sender that senses a ferro magnet insert on the flywheel. Apparently unusual for them to break down (good thing given the price)

 

[Dan Johnson]

Richard...

I had trouble with my tach reading right a couple of seasons ago. Cleaned all the connections and tightened down the crimps on the female connectors and the problem went away.

 

[Richard Bryer]

Re: Richard...

Well. There are some things that just seem to need a good taking apart. I have always believed that even as a child- I just wasnt so good at getting them back together!
I pulled the sending unit, tried the John Deere and Kubota dealers, only found parts guys too lazy to dig up a part without a part number, so went back and put the sender back in planning to do more searching before I parted with $200 plus our exorbitant taxes. Put it back, thought I would just start the engine just on the off chance....- sure enough it now works. Go figure. I am happy with the 200+ still in my jeans. Thanks all for your help- Dan you were probably right on- the removal probably cleaned the contacts

 

[Dan Johnson]

Richard...

before I tighten down the flanges on a female connector, I give it a good soaking of alcohol and slide the male part in and out several times to clean the connection (Phil: don't move this to the "Off-topic, Adult forum--it's legitimate!).