Mitchell Tachometer

[flyboy0681]

The hours meter on the original tach stopped cold dead a few weeks ago. I'd like to order a new Mitchell tach from Aircraft Spruce but the site doesn't make it easy because too little information is given on which one to order. Adding to the confusion is the average RPM's listed on the unit that I think I need (model # D1-112-5023) as being 2,300.  I do like that idea that silk screening and the hours can be preset, but I can't determine which item to order.

Has anyone here replaced theirs recently, and if so, what is the actual part number to order. This is for a 1983 J.

BTW, my partners and I want a simple replacement and not go through the expense of an electronic tach. This is due to last months $12k expense of having the tanks resealed.

[Pinecone]

According to Frank Crawford at Mooney, the tachs are 2500 for 1 to 1.

[N201MKTurbo]

Buy a UMA electronic tach and you will never have a tach issue again. Easy install and costs little more than the Mitchell. I must have bought 3 Mitchell tachs before I finally gave up on them.

[Fly Boomer]

2 hours ago, N201MKTurbo said:

Buy a UMA electronic tach and you will never have a tach issue again. Easy install and costs little more than the Mitchell. I must have bought 3 Mitchell tachs before I finally gave up on them.

Any experience or thoughts on the UMA vs EI R-1 tach?

[Andy95W]

2 hours ago, Fly Boomer said:

Any experience or thoughts on the UMA vs EI R-1 tach?

My Mitchell tach went out a few years ago so I installed an UMA. I ordered it through Aircraft Spruce but then communicated with the company (UMA) to “personalize” my new tach with the correct hours and red/green arcs.

That process was kind of a pain, but it went off smoothly and I couldn’t be happier with the result.  I had a digital tach in my last airplane and really wasn’t a fan of watching the rpm dance around. I really love the UMA. Installation was pretty easy and straightforward. I installed the sensor in my right magneto in case I ever change to a Surefly. Works great. 

[201Mooniac]

@flyboy0681 I have a fairly new Mitchell tach from a 1980 M20J available if that would help.  I replaced the tach about 1.5 years before installing a GI275 EIS.  It currently shows 211 hours.  The part number is D1-112-5026.  If you are interested, feel free to make an offer, it is just sitting on my shelf.

[flyboy0681]

10 hours ago, 201Mooniac said:

@flyboy0681 I have a fairly new Mitchell tach from a 1980 M20J available if that would help.  I replaced the tach about 1.5 years before installing a GI275 EIS.  It currently shows 211 hours.  The part number is D1-112-5026.  If you are interested, feel free to make an offer, it is just sitting on my shelf.

Thanks for the offer, but unless the clock could be set to our current value, we'll have to pass.

[N201MKTurbo]

Not that I'm advocating illegal instrument repair, or using a Mitchell tach, which I'm not, but changing the time on a Mitchell tach isn't hard.

[Bolter]

7 minutes ago, flyboy0681 said:

Thanks for the offer, but unless the clock could be set to our current value, we'll have to pass.

While it is obviously convenient to have the tach values match your actual, you can note in the logbook a new tach installed, and then TTAF and Tach for future entries will just be different from each other by a constant amount.  

[flyboy0681]

2 minutes ago, Bolter said:

While it is obviously convenient to have the tach values match your actual, you can note in the logbook a new tach installed, and then TTAF and Tach for future entries will just be different from each other by a constant amount.  

True, but the partners decided that we want the actual numbers displayed.

[201Mooniac]

1 hour ago, flyboy0681 said:

Thanks for the offer, but unless the clock could be set to our current value, we'll have to pass.

No problem, just so you know, any instrument shop will set the time for you. 

[jetdriven]

We installed an SLI tach and they shipped it with the hours requested. It’s got another 800 hours on it since then and it’s deadass.