Tachometer

[pimpo 6]

So what Tachometer are you using to set rpm on your engines? 

Advice 

[Marv 914]

I am still using a hand held vibrating tach. have had the thing 48 years.

Marv

[ebinmaine 67,013]

I have a cheapo modern light reader type. 

It reads by having a piece of silver or white tape or paint on the rotating part.  

 

 

[Handy Don 12,040]

I use this app on my iPhone--the free version. Same principle as the one @ebinmaine uses.

 

[Steve Janninck 170]

I finally found a digital dash mounted tachometer that works with a single cylinder engine. Very accurate when compared with an optical tach. I figured that digital might be better to handle the tractor vibrations than a needle style. It marries up nicely to the digital volt meter I installed a few years ago.

[Handy Don 12,040]

This is a nice add.

I’ve been sporadically looking for a digital ammeter that can display current in both directions (i.e. “+” and “-“). Everything I’m finding is one-way only.

[Bill D 1,888]

3 hours ago, Steve Janninck said:

I finally found a digital dash mounted tachometer that works with a single cylinder engine. Very accurate when compared with an optical tach. I figured that digital might be better to handle the tractor vibrations than a needle style. It marries up nicely to the digital volt meter I installed a few years ago.

Could you please tell us where you bought it, and maybe share a link.  Thanks.  

 

I have a timing light with a built-in tachometer.  I like the idea of adding one on the tractor, especially with the Onan's and their governor issues.

Edited July 25 by Bill D

[Steve Janninck 170]

3 hours ago, Handy Don said:

This is a nice add.

I’ve been sporadically looking for a digital ammeter that can display current in both directions (i.e. “+” and “-“). Everything I’m finding is one-way only.

Don,

I have installed a 2 inch round Volt / Amp gauge in an RV that was pretty nice. It had a remote shunt that I mounted out at the battery, and there was a harness that went from the shunt to the gauge. I probably should have bought one of those because it displayed Voltage, + and - Amps, and Battery percentage. Would work great if you were wanting a combined indicator. I think it was like 30 bucks.

Steve

Digital AMP / Volt 2 Inch with Remote Shunt

Link added.

Edited July 25 by Steve Janninck
adding Link

[Steve Janninck 170]

45 minutes ago, Bill D said:

Could you please tell us where you bought it, and maybe share a link.  Thanks.  

 

I have a timing light with a built-in tachometer.  I like the idea of adding one on the tractor, especially with the Onan's and their governor issues.

Bill,

I purchased though Amazon, it was the cheapest there.

Single Cylinder 2 Inch Tach

The Tach can be set from 1 to 8 cylinders, so should work on twin cylinders also.

Three connections.

1. for the Positive (Red)

1. for the Negative (Black)

1. for the Points Side of the Coil (Green)

Unit programs with a push button on the back, once it set, it retains its setting.

If you go to the customer reviews on this tach, you will see my video of the Tach in operation. 

Hope this helps!

Steve

[Handy Don 12,040]

36 minutes ago, Steve Janninck said:

Don,

 it displayed Voltage, + and - Amps,

Thanks for the link.

 

Have you actually seen this behavior?

This is from the spec: " voltage range 8V-80V and current range 0-100A"

If it were capable of displaying amperage in both directions, I’d expect it to properly list this as “0 - ±100A” or some equivalent notation -- but it doesn’t.

 

In the later details on the listing, it does have this:

Which implies that it shows positive and negative current flows as charge and discharge.

So this is an intriguing item and for someone relying on batteries (like the RV you mention) I can see the value. I am skeptical of both the capacity display and the suggestion in the details that one fully discharge a battery to then “zero” the monitor. The former is going to be an approximation and would be heavily affected by the type of battery involved--lead-acid, gel, lithium, marine deep cycle, etc.. The latter is a just plain bad idea for lead-acid batteries.

 

 

 

[Steve Janninck 170]

5 minutes ago, Handy Don said:

Thanks for the link.

 

Have you actually seen this behavior?

This is from the spec: " voltage range 8V-80V and current range 0-100A"

If it were capable of displaying amperage in both directions, I’d expect it to properly list this as “0 - ±100A” or some equivalent notation -- but it doesn’t.

 

In the later details on the listing, it does have this:

Which implies that it shows positive and negative current flows as charge and discharge.

So this is an intriguing item and for someone relying on batteries (like the RV you mention) I can see the value. I am skeptical of both the capacity display and the suggestion in the details that one fully discharge a battery to then “zero” the monitor. The former is going to be an approximation and would be heavily affected by the type of battery involved--lead-acid, gel, lithium, marine deep cycle, etc.. The latter is a just plain bad idea for lead-acid batteries.

 

 

 

Don,

I helped a guy install this in a Sprinter RV which was all 12V Lead Acid. he has 2 batteries One for the engine and the other for the camper side. He could charge the camper side with his generator, or when he ran the engine. The Shunt was mounted on the Negative side of the Camper battery. It worked great, but I don't think I ever saw a discharge or charge of more than 10 AMPs when we were testing it. This guy did a great video of the gauge installed on a golf cart. He shows the discharge, then the recharging AMPS. You can then understand how this would work on a simple tractor Lead Acid 12-volt system. I really don't understand battery voltage vs percentage, not really need in this application.

Video - Battery Monitor Voltmeter Ammeter Kit with Shunt

Interesting stuff!

Steve

 

[Bill D 1,888]

1 hour ago, Steve Janninck said:

Bill,

I purchased though Amazon, it was the cheapest there.

Single Cylinder 2 Inch Tach

The Tach can be set from 1 to 8 cylinders, so should work on twin cylinders also.

Three connections.

1. for the Positive (Red)

1. for the Negative (Black)

1. for the Points Side of the Coil (Green)

Unit programs with a push button on the back, once it set, it retains its setting.

If you go to the customer reviews on this tach, you will see my video of the Tach in operation. 

Hope this helps!

Steve

Very nice.  Thanks for the info.  

[Handy Don 12,040]

4 minutes ago, Steve Janninck said:

Don,

I helped a guy install this in a Sprinter RV which was all 12V Lead Acid. he has 2 batteries One for the engine and the other for the camper side. He could charge the camper side with his generator, or when he ran the engine. The Shunt was mounted on the Negative side of the Camper battery. It worked great, but I don't think I ever saw a discharge or charge of more than 10 AMPs when we were testing it. This guy did a great video of the gauge installed on a golf cart. He shows the discharge, then the recharging AMPS. You can then understand how this would work on a simple tractor Lead Acid 12-volt system. I really don't understand battery voltage vs percentage, not really need in this application.

Video - Battery Monitor Voltmeter Ammeter Kit with Shunt

Interesting stuff!

Steve

Your comments and the video are really helpful, thanks.

He showed the shunt in-line with everything on the cart. In the RV camper battery this would also work as nothing is likely to draw anything near 100 amps. 

 

In a tractor setting, though, this would include the starter motor which (from my quick internet search) could easily draw 100+ amps on a cold start and possibly overload the shunt.

On Wheel Horses with ammeters, the only juice passing through the ammeter is the draw needed for the ignition coil plus accessories and the charge from the stator/generator so the hookup would be different. 

 

Still, I’m tempted to replace the analog voltmeter on the 312 with one of these as an experiment (my 854 has both ammeter and voltmeters and I can live without a tach!)

[ebinmaine 67,013]

3 hours ago, Steve Janninck said:

Bill,

I purchased though Amazon, it was the cheapest there.

Single Cylinder 2 Inch Tach

The Tach can be set from 1 to 8 cylinders, so should work on twin cylinders also.

Three connections.

1. for the Positive (Red)

1. for the Negative (Black)

1. for the Points Side of the Coil (Green)

Unit programs with a push button on the back, once it set, it retains its setting.

If you go to the customer reviews on this tach, you will see my video of the Tach in operation. 

Hope this helps!

Steve

 

 

I've ordered one of these tachometers as well. I've held off putting one on a tractor for several years for a few different reasons but I've recently discovered that the RPM on one of mine has slowly decreased over the 5 years it's been in service. Might be nice to know what it really is most of the time. For 17 bucks I'll give it a shot.

[Steve Janninck 170]

3 hours ago, Handy Don said:

Your comments and the video are really helpful, thanks.

He showed the shunt in-line with everything on the cart. In the RV camper battery this would also work as nothing is likely to draw anything near 100 amps. 

 

In a tractor setting, though, this would include the starter motor which (from my quick internet search) could easily draw 100+ amps on a cold start and possibly overload the shunt.

On Wheel Horses with ammeters, the only juice passing through the ammeter is the draw needed for the ignition coil plus accessories and the charge from the stator/generator so the hookup would be different. 

 

Still, I’m tempted to replace the analog voltmeter on the 312 with one of these as an experiment (my 854 has both ammeter and voltmeters and I can live without a tach!)

Don,

It would be really interesting to get a test done. They do sell one for a couple bucks more that goes up to 350 Amp capability. Thinking just an upsized shunt. I think tractor batteries have about a 300 CCA rating.

Keep the thread posted if you try a test!

Steve

[Steve Janninck 170]

On 7/25/2024 at 3:21 PM, ebinmaine said:

 

 

I've ordered one of these tachometers as well. I've held off putting one on a tractor for several years for a few different reasons but I've recently discovered that the RPM on one of mine has slowly decreased over the 5 years it's been in service. Might be nice to know what it really is most of the time. For 17 bucks I'll give it a shot.

The tach is definitely more purposeful on the high end. I really like to know the high end RPM, because when operating it lives there. I have to say I have made a governor adjustment since installing. I found as the K321 14HP warms up, the rpm increases about a 150 rpm. I would have never caught this. Easy to dial it back so when she if full bore warmed up she is right at max designed RPM. As far as using for idle, might be useful at a carb replacement but they all idle somewhere around a 1000 rpm give or take.

Steve 

[ebinmaine 67,013]

5 minutes ago, Steve Janninck said:

As far as using for idle, might be useful at a carb replacement but they all idle somewhere around a 1000 rpm give or take.

Steve 

 

I'm definitely more interested in the RPM range of around 2800 to 3600.  

 

The idle is a bit of a moot point anyway because these engines shouldn't even be at idle unless just before shutdown. 

 

I tend to set our machine's idles by ear more than tach. 

Trina's smaller 8 HP engines are happier lower RPM than my K341s. 

My Cinnamon Horse C160-8 likes to idle more around 1300. 

 

 

[Handy Don 12,040]

On 7/25/2024 at 4:21 PM, ebinmaine said:

've ordered one of these tachometers as well.

Remembered that I wanted to add that if you have the 100 amp max version of the gadget, you’ll want to put the shunt, in its correct polarity, between the battery plus terminal and the ignition switch B terminal. This will catch current for ignition (non-magneto),  accessories, and charging only. In a tractor that had an ammeter, put the shunt in place of (or in series with) the meter.

Putting it inline with the battery negative to frame/block connection will expose it to starter motor amperage and likely blow the shunt.

Tach connection is as instructed!

Edited July 31 by Handy Don

[Steve Janninck 170]

1 hour ago, Handy Don said:

Remembered that I wanted to add that if you have the 100 amp max version of the gadget, you’ll want to put the shunt, in its correct polarity, between the battery plus terminal and the ignition switch B terminal. This will catch current for ignition (non-magneto),  accessories, and charging only. In a tractor that had an ammeter, put the shunt in place of (or in series with) the meter.

Putting it inline with the battery negative to frame/block connection will expose it to starter motor amperage and likely blow the shunt.

Tach connection is as instructed!

Don,

Great point.

I really use the voltage meter as my poor man's Amp Meter. If I see 13 + volts I know I am charging. If I see anything south of 12 volts, I know I am discharging.

Good to hear the Tach is working!

Steve

[ebinmaine 67,013]

On 7/25/2024 at 12:58 PM, Steve Janninck said:

Bill,

I purchased though Amazon, it was the cheapest there.

Single Cylinder 2 Inch Tach

The Tach can be set from 1 to 8 cylinders, so should work on twin cylinders also.

Three connections.

1. for the Positive (Red)

1. for the Negative (Black)

1. for the Points Side of the Coil (Green)

Unit programs with a push button on the back, once it set, it retains its setting.

If you go to the customer reviews on this tach, you will see my video of the Tach in operation. 

Hope this helps!

Steve

 

Steve  do you recall what the setting is to get a single cylinder reading? 

 

Just  keep pushing the button on the back until it reads right?

 

 

 

[Steve Janninck 170]

9 minutes ago, ebinmaine said:

 

Steve  do you recall what the setting is to get a single cylinder reading? 

 

Just  keep pushing the button on the back until it reads right?

 

 

 

Eric,

If you have a single cylinder, let the engine idle and press the button until you see the highest reading. Depending on your idle setting it’s going to be north or south of at a 1000 RPM. The smallest number would be for 8 cylinders. The largest number for 1 cylinder. Once set take the engine to full throttle and if set correctly should be north of 3000, my governor is set at 3350 RPM as an example.

Hope this helps!

Steve