Tachometer problem on 3YM30
- Thread starter rajhnsn
- Start date
I mentioned this in a previous thread. Have the 3YM20. Hobbes meter comes on intermittently and, then, only for a few seconds. The hours are recorded, however. Whenever I do see the hours displayed, I immediately write it down. Seems to be a recurring problem with this unit.
Some previous posts may have some suggestions:
http://forums.sailboatowners.com/index.php?threads/engine-hour-lcd-meter-repair.148593/
http://forums.sailboatowners.com/index.php?threads/engine-hour-lcd-meter-repair.148593/
Thanks for posting that thread. I've been dealing with this for several years, now. I may have to look into NorthStar's fix at a later date.
Since the tachometer is working I would continue to use it and install a separate external hour meter. You can wire a new hour meter to the key switch circuit.
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Just seen the Northstar solution but also the comment that the procedure did not fully correct his problem. I'm not keen to be opening up the tachometer housing unnecessarily. The suggested procedure is rather delicate and there are no guarantees that it will solve the problem. Still believe the most sensible solution is to install and external hour meter. Years ago I installed an electro-mechanical hour meter and to this day is working like a charm. The unit I believe was under $20 and got it online.
Yeah, I'm not too keen on tearing the tach apart and making the situation worse. I'm going to need advice on how to mount one in the engine room or just outside of it, however.
Installing an hour meter by the engine compartment is a good idea as it would be protected from the elements. In the wire harness from the engine to control panel run the wires that power the key switch circuit. Identify the (+) wire carrying power to the panel and insert the hour meter connectors into the circuit. When the key switch is turned on and closes the circuit the hour meter will be powered.
This is the standard Yanmar instrument panel... The hour display goes blank. I did the repair above only to see the unit go blank again. A new unit is around 600$CDN. As above mentioned I bought an external hour meter and connected it to a 12V source for about a month (in winter) to run up the hours to what was on the engine. I installed it in a protected area close to the ignition. Flawless for the last three years.