Tach Repair YM276D

[richriddle]

The tach on the YM276D (it might be mechanical) needs repair because the indicator fell off and is laying inside. Is there either a replacement tach that one may order or do any of you know of a place where you can send the tachometer in for repair? Can one order the parts and simply repair a tachometer? Thanks.

 

[Menagerie-Manor]

If the needle just separated from the post then it can be pressed back on as it should be a friction fit.

 

[richriddle]

I see the shaft and needle as one piece under the glass.

 

[California]

You need to find an automotive speedometer shop or precision instrument repair/calibration shop, that can provide and install the band around the face that you need to pry off to get into the tach. Without that new band installed using specialized equipment, you wouldn't be able to make it watertight.

 

[winston1]

Don't know they have one, but they do have a price fixed to it. HOUR METER ASSEMBLY - No Longer Sold New

 

[bmaverick]

The tach on the YM276D (it might be mechanical) needs repair because the indicator fell off and is laying inside. Is there either a replacement tach that one may order or do any of you know of a place where you can send the tachometer in for repair? Can one order the parts and simply repair a tachometer? Thanks.

I would assume the hour meter gauge is clearly marked Nippon-Seki.

You can do a search on the web for YT video,

nippon seiki tachometer repair

Nippon-Seki made motor scooter and motorcycle gauges from the late 60s till now. Those old 70s versions are like our Yanmar versions. Honda and Suzuki 70s gauges come apart the same way. So, learn the EZ skills from these people to take apart, fix and reassemble. Simple garage and kitchen tool needed.

 

[California]

.. Honda and Suzuki 70s gauges come apart the same way. ... Simple garage and kitchen tool needed.

Interesting! I took apart and cleaned/repaired the tach on a 50's BSA motorcycle long ago, same as you described.

Then my first YM186D had a screechy, jumpy tach so I attempted a similar repair. I concluded it could only be opened by destroying the ring that holds the face glass on. So I turned it face down and 'oiled' it with a couple of drops of lock fluid (graphite in solvent) around the input shaft. Let it sit face down overnight for the graphite to run in. That fixed it, good for another 20 years.

But that wouldn't help if the needle fell off.

 

[richriddle]

Here is a picture of the tachometer we are discussing.

 

[bmaverick]

Here is a picture of the tachometer we are discussing.

WOW, at 24KPH, the machine is cruising at high speed of 15MPH.

It would be really nice to have the needle pointing correctly. Your benefit is the Engine RPMs with a 0 (zero) location. Thus, with the tachometer taken apart, note where that sits to align it.

It's worth the try opening it up, taking your time, getting the shaft re-bonded and the needle pointed correctly. Not only engine RPMs, the PTO is important. then the hours on the meter too.

Like 'California' mentioned, once it's all done, seal it back up on the chrome ring with something that is like the plumbers putty or something should anyone need to get in there again. Just good enough to keep wetness out.

Watching those vids, I would have a better grasp on how to repair these now. Event a new needle 3D printed in polycarbonate would last decades. Just in case the needle is beyond repair and a new one needs to fit and work.

FreeCAD v19 is now out. And it's FREE.

https://www.freecadweb.org

Once 3D modeled, you can export to an STL file for 3D printing. Ensure the tight tolerance is retained for the STL. And thicken up the needle a shade for durability. 3D printing needs at least 5 good layers to be useable (2mm)