Tachometer not working

[TimP]

Hi All.

I have a B3000HSDCC.

I went to try out my snowblower this morning, and I noticed that my Tachometer was not working.

Not moving at all.

It was working a few days ago.

Is the Tach on this tractor a mechanical Tach or electrical?

Any suggestion on what and where to look/check to identify a problem with the Tach?

Thank You for any assistance.

 

[number two]

Bummer!
I think your tach is mechanical.
If it is like my B3030,it's a white faced gauge with a red needle.

If it's a digital tach like a B2650,then it is electronic.

Assuming it's mechanical like mine,it's cable driven.
Cable runs from the back of the gauge to the engine(fuel pump?)
Access the back of the tach and disconnect the cable.
Start the engine and observe the cable turning or not.
Cable not turning is almost always a broken cable.

Good Luck!

 

[OzKioti]

If it's a cable type, it does need to be serviced periodically. Take it out, clean it, soak it in oil, and reinstall it. Easy to overlook in the bigger scheme of things - engine oil, transmission/hydraulic, front axle etc.

A sure sign it's in need of TLC is wild fluctuations in indicated engine RPM.

 

[Bird]

This reminds me of the first vehicle of any kind that I owned with a tachometer; a new 1962 Austin Healy Sprite. And, while it was still in warranty, the tachometer would work a little bit, slow to increase when I increased speed, etc. So the dealer's mechanics decided they'd just have to replace the tach display in the dash. Now the dealer was in Dallas, but they had to send someone to Ft. Worth to get a tachometer. Once they got it all changed out . . . . same as the original one. Now the tach was driven by cable off the back of the alternator. They finally figured out that the only problem was a fan belt slipping. Tightening the fan belt fixed the problem.:laughing:

 

[denchen]

Many years ago, I used to have a car that when going up the road you knew you was doing between 25 and 85 mph. As there was only about 35 horses in the front, and some of those were dead, it was anyone's guess. Usually a drop of oil in the cable would settle things down. Taco`s can be the same.

 

[TimP]

Thanks to everyone who responded.

I did finally find what appears to be the cable on the parts diagram, (Part #35300-99343).

The cable isn't too expensive ($28). But if the Tachometer itself is bad..... WHOAH ! That's $700 from what I see on the parts diagram.

The next order of business will be to remove the dash to gain access to the back of the Tach to disconnect the cable.

If the cable isn't spinning (hopefully that's the case) then just replace the cable. If cable "IS" spinning, it's a problem with the Tach itself. (BAD)

I have read some posts that claim their Tach was "frozen" and they were able to free it up with a little "force". Nothing to lose in that case.

Now..... anyone here ever removed their Dash for any reason? How difficult is it? Any tips for removing the Dash?

Thanks again!

 

[OzKioti]

On my older tractor (LG N47) I undid the cable at the engine end, and simply extracted the inner part. It resembles a tightly wound spring, flattened each end into a square shape. When replacing it, push it up inside the outer and rotate it slightly to slot into the square "socket" in the tacho display unit.

So maybe I was lucky, but I didn't ever have to do surgery on the dash. Hope yours is similar.

 

[California]

I had a jumpy tachometer on my 40 year old Yanmar. After diagnostics and cable maintenance as described above, it was clearly internal to the tach.

I took the tach out, turned it face down, and dribbled a little lock fluid (graphite in solvent) around the shaft into the tach.

Problem solved. It worked same as new for the several years I had that tractor.

That risked visibly staining the face of the tach but that didn't happen.

I would try this, or even dis-assembly, before spending $700 on a new one. There are instrument repair shops in major cities who can replace the sealing band that holds the face on the shell.

 

[TimP]

On my older tractor (LG N47) I undid the cable at the engine end, and simply extracted the inner part. It resembles a tightly wound spring, flattened each end into a square shape. When replacing it, push it up inside the outer and rotate it slightly to slot into the square "socket" in the tacho display unit.

So maybe I was lucky, but I didn't ever have to do surgery on the dash. Hope yours is similar.

Thanks for the info.

I am hoping that it's the cable as that sound like an easier fix.

But your info will help a lot if it's NOT the cable.

 

[TimP]

I had a jumpy tachometer on my 40 year old Yanmar. After diagnostics and cable maintenance as described above, it was clearly internal to the tach.

I took the tach out, turned it face down, and dribbled a little lock fluid (graphite in solvent) around the shaft into the tach.

Problem solved. It worked same as new for the several years I had that tractor.

That risked visibly staining the face of the tach but that didn't happen.

I would try this, or even dis-assembly, before spending $700 on a new one. There are instrument repair shops in major cities who can replace the sealing band that holds the face on the shell.

Thanks for the insight.

Even if the cable is the fix, I may as well see if I can get some lube into the Tach since I would have the dash off anyway.

Thanks again !