Adding a Tach to Ford 5000

Hi guys,

Has anybody tried to add an external tachometer to a diesel tractor? Since I'm new to this tractor thing, I'd like to have some sort of indication of what my RPMs actually are. There is no hour meter as well.

The guy who sold me my Ford 5000 tractor said that the tachometer cable (of the instrument cluster) is not connected to anything because, it used to be - supposedly - connected to the generator, which he replaced with a modern alternator, because he didn't want to pay the extra money for an original part; the AC/DC converter box is also missing, so the charging fire goes to the battery directly from the alternator.

On the other hand, I see that my parts catalogue refers to some "Pump to Tachometer Adapter" (items 124, 125, 126 on page 09E02 inlet), so maybe the guy was wrong, and the tach cable is connected to something else? I can't really get a clear view of the front of the engine.

I see that there are tachometers / hour meters on the internet that have an external weatherproof display, but most of them are for gas engines, i.e. work off the ignition impulse. There are some devices that feature a magnet sensor, but those that I've found are not weatherproof.

Suppose I find a tach with a magnet sensor. Where would I install it though? On the alternator / power steering pump wheel? Then how would I calibrate it then? I thought I could buy a laser RPM meter, attach the light reflecting sticker to the PTO use it as a reference (knowing the known crankshaft-to-PTO ratio).

Any ideas?

Thanks,
Jaroslav


[img:15b87c2579][/img:15b87c2579]

Tach is connected to generator on all 5000's unless it changed at the very end. Your retrofit with a single wire alternator is very common. There is a kit available to hook the tach to the rear of the alternator, I ordered one; but lost confidence in it working after opening the package. Never tried it. If I have a working tach, I keep it working. If I buy it broke, it gets a single wire alternator, push button start, wiring and voltage regulator removed and temp and oil pressure gauge mounted on plate in the place of the broken tach/gauge assembly. If you need/want a tach, I would take it back to original. If it hasn't been working for a while, it will probably require a new tach/gauge panel, cable, voltage regulator, generator, possibly generator mount- if the original was modified and a new wiring harness and key switch. I have them both ways...

If made after 3-68 should have cup style freeze plug below oil filter. Take it out replace oil pump drive gear, get adapter and new style cluster.

(quoted from post at 22:48:06 10/12/21) If made after 3-68 should have cup style freeze plug below oil filter. Take it out replace oil pump drive gear, get adapter and new style cluster.

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Well, my tractor is from 1965. Do you see the "cup style freeze plug below oil filter" in the picture below?

Looks like you have the threaded in plug, not the freeze plug style. The threaded type has a large 1 inch hex in it, immediately underneath
the oil filter.

As for the adapter that you're looking at, that was meant for 7000 tractors when they originally came out with an alternator. Even if you
could find such an adapter, I don't think you could easily retrofit it to the back of the injection pump. Your best bet if you want a working
tach would be to convert it back to the original generator setup, because the aftermarket Delco kits with the tach drive are notoriously
inaccurate.

(quoted from post at 22:13:06 10/12/21) There is a kit available to hook the tach to the rear of the alternator, I ordered one; but lost confidence in it working after opening the package. Never tried it.... If you need/want a tach, I would take it back to original...

Click to expand...

I'm not religious about making it all original. I just wanna know what RPM it spins the PTO.

So, what kind of kit was that? I saw a Tach product on https://www.youtube.com/watch?v=HhLPAPZxNsM that works off the alternator, but I didn't like the gauge.

Don't know what the setup you're thinking about will cost, but did some quick google searching and came up with:

Alternator kit with tach drive $140
Instrument cluster ... gauges, tach, hour meter $90
Tach drive cable $15

Don't know how much of the original wiring is still there, but something to think about.

Done a few of the thousand series alternator conversions, and am about to do another. Of course, my tractors still have the tach cable and cluster, so I don't need to spring for those.

Have noticed I need to have the tach read about 2100 rpm instead of 1900 rpm to get my 540 rpm pto speed with these conversions.

Fred

If it mattered... a guy could probably asjust the tach to pto ratio with a different size pulley on the alternator.

(quoted from post at 00:13:14 10/14/21) Don't know what the setup you're thinking about will cost ... Don't know how much of the original wiring is still there...
Fred

Click to expand...

I've replaced the entire harness. The original instrument panel is there and I am keeping it: oil and battery indicators work and it's all that matters for me.

The fuel tank level goes up to the middle even when full, but I'm not too concerned (I've noticed that the tractor starts stalling at the idle when the tanke becomes half empty, which is odd, given that I've replaced the fuel filters recently).

The temperature sensor's niddle also hardly moves, and this does concern me, as I want to know if the engine is overheated or the thermostat is not working. I'm gonna install this TrailTech temperature sensor: https://www.trailtech.net/en-us/sho...mperature-black-probe-sensor-1-8th-x-28-bspp/

For the tachometer, I found a convenient, but pricey option: it's a pair of Auto Meter RPM Signal adapters, [b:55ef433d36]9112[/b:55ef433d36] (https://www.amazon.com/Auto-Meter-5...+signal+adapter&qid=1634219732&sr=8-1) and [b:55ef433d36]5315[/b:55ef433d36] (https://www.amazon.com/Auto-Meter-9...+signal+adapter&qid=1634219754&sr=8-1). This should work with any standard tachometer, which is extra. However, all the tachs I could find are made fancy for motorcycles, and where would I even install it. I'd rather have a plactic box with an LCD display.

I also found a whole bunch of hour battery meters, which work by detecting vibrations. You just stick it on the tractor - no wiring required (https://fortnine.ca/en/moose-wireless-hour-meter-2212-0426).

I even came across a wireless tachometer / hour meter that claimed that it detects the RPM by sensing engine harmonics, but I can't find it for some reason.

Has anybody tried these wireless sensors?

I have one 4000 and a 5000 with Delco 10SI tach drive alternators, the original generator pulleys were larger diameter so we bored them to fit the Delco shaft, this slowed the tach speed by a hundred rpm but the tachs are still off a couple hundred rpm
I adjusted engine speed to get 540 pto rpm on my digital tach and then put a small mark on the tractor tachs glass were the needle was pointing, now when using pto equipment I set engine speed to the mark on the dash
It doesnt mater what the tach is showing or what the actual engine speed is as long as the pto is turning the recommended 540 rpm

The 5600 shows 540 pto at 1900 engine rpm my disc mower sounded like it was running slow, checked the pto speed with my digital tach to find the pto was only turning 460 rpm
To get 540 pto the tractors tach needs to show 2100, dont know if the original tach is off or if its mechanical but it doesnt really matter, I now just pull the throttle back to 2100 and the mower sounds good and cuts better

(quoted from post at 10:29:12 10/14/21)
I have one 4000 and a 5000 with Delco 10SI tach drive alternators, the original generator pulleys were larger diameter so we bored them to fit the Delco shaft, this slowed the tach speed by a hundred rpm but the tachs are still off a couple hundred rpm
I adjusted engine speed to get 540 pto rpm on my digital tach and then put a small mark on the tractor tachs glass were the needle was pointing, now when using pto equipment I set engine speed to the mark on the dash
It doesnt mater what the tach is showing or what the actual engine speed is as long as the pto is turning the recommended 540 rpm

The 5600 shows 540 pto at 1900 engine rpm my disc mower sounded like it was running slow, checked the pto speed with my digital tach to find the pto was only turning 460 rpm
To get 540 pto the tractors tach needs to show 2100, dont know if the original tach is off or if its mechanical but it doesnt really matter, I now just pull the throttle back to 2100 and the mower sounds good and cuts better

Click to expand...

.....and with no tractor tach, why not use pto tach and put that "small mark" on the throttle for 540 position?

(quoted from post at 11:57:11 10/14/21)

(quoted from post at 10:29:12 10/14/21)
... I adjusted engine speed to get 540 pto rpm on my digital tach and then put a small mark on the tractor tachs glass were the needle was pointing, now when using pto equipment I set engine speed to the mark on the dash...

Click to expand...

.....and with no tractor tach, why not use pto tach and put that "small mark" on the throttle for 540 position?

Click to expand...

There is a significant gap between the throttle handle and the body panel, so the question is how accurate it's gonna be. Also, can we assume that RPM are controlled solely by the position of the throttle and are not affected by the load.

(quoted from post at 12:43:53 10/14/21)

(quoted from post at 11:57:11 10/14/21)

(quoted from post at 10:29:12 10/14/21)
... I adjusted engine speed to get 540 pto rpm on my digital tach and then put a small mark on the tractor tachs glass were the needle was pointing, now when using pto equipment I set engine speed to the mark on the dash...

Click to expand...

.....and with no tractor tach, why not use pto tach and put that "small mark" on the throttle for 540 position?

Click to expand...

There is a significant gap between the throttle handle and the body panel, so the question is how accurate it's gonna be. Also, can we assume that RPM are controlled solely by the position of the throttle and are not affected by the load.

Click to expand...

orks for me, but maybe not for all? What do you need? 1%, 1/2 %, 10%???

(quoted from post at 12:54:19 10/14/21) Works for me, but maybe not for all? What do you need? 1%, 1/2 %, 10%???

Click to expand...

I like the idea very much!

I might stick some sort of vertical indicator (on a magnet) on top of the "small mark" to make it more user friendly.

Could...but that souunds like more work .

Every one I've converted has been off that much, so I just run 2100 rpm indicated when 540 pto rpm is required.

Fred

There is a significant gap between the throttle handle and the body panel, so the question is how accurate it's gonna be. Also, can we assume that RPM are controlled solely by the position of the throttle and are not affected by the load.

Click to expand...

There should be a rubber grommet taking up that space
The engines governor will add or take away fuel according to load in order to maintain the rpm set by the throttle lever
One could mark the throttle levers position but for a taller or shorter person setting in a different position will cause the mark to be off for them.

I was able to measure my engine's RPMs with an iPhone App called the [b:3151e11fd7]Engine RPM[/b:3151e11fd7] (https://apps.apple.com/us/app/engine-rpm/id340401811). It measures RPM by listening to the sounds produced by the engine. You have to tell the app whether you have a two-cycle or 4 cycle engine and the number of cylinders. It essentially detects the dominant frequencies produced by the engine.

It wasn't without a problem though. When I started upping the rev from 640 to 1900 (to get the 540 at the PTO) the app got confused and started giving me values 4 times lower the actual ones. So, the proper 1900 RPMs were acheved at 475 RPM shown by the app. But to be fair, I used only the simple "Auto-ranging Mode", which the manual does say could produce double or half readings. Next time I'll try turn off the Auto-ranging Mode and give the app a hint of what RPMs it is to expect.

How do I know that it was the correct RPM? Well, I confirmed it using another iPhone app: [b:3151e11fd7]Video Tachometer[/b:3151e11fd7] (https://apps.apple.com/us/app/video-tachometer/id1492583587)[/url]. You have to pay a couple bucks to unlock some features.

I painted a white dot on the side of the PTO shaft, then pointed the camera at the shaft and set the frequency at 540 RPM, at which point the picture became static, as if the shaft wasn't rotating at all.

The amazing part is that the values obtained with two methods agreeded between themselves within 1-2 RPMs.

In practicality, all I need to do now is just make an "indicator" out of piece of wire, attach it to the throttle handle and do the "small mark" on the steering column at the 540 PTO RPM. And Bob's your uncle!

This post was edited by jrslv on 10/19/2021 at 03:40 pm.