Clusters, Gauges, Speedo & Odo meters (1 Viewer)

[amaurer]

Rudi/Tom - its now many pages back, but I have remembered our ammeter playtime over these year... since I now have a battery that dies mysteriously, I was finally galvanized (ha, electrical pun!) to action.

I thought of all kinds of fancy methods for making shunts and eventually ignored them all and just went with 18" of coiled 14ga wire. I should have used fusible link wire, but I didn't... famous last words, perhaps.

Anyway, ammeter works great now, perhaps one of the first 1980+ cruiser ammeters in history to do so.

 

[bj40green]

Drew, that is f****ing great!
So you did follow up on your testing in posting #78 on page 4 earlier in this thread were you mentioned:

14 gauge wire gives you ~.004ohms per foot, so to get the 0.1ohms you need to produce proper needle deflection the link MUST be a full 1.5 feet (45cm) long.

Well, 18" is 1½ foot is 46 cm!
Finally a solution for those non working 50-0-50 Ammeters. I agree with you that it's better to use Fusible Link wire or use a bare copper wire and put shrinkable tube on it. In the end..... it's still a Fusible Link.

Great job Drew.

Rudi

 

[Biscuit]

I thought of all kinds of fancy methods for making shunts and eventually ignored them all and just went with 18" of coiled 14ga wire. I should have used fusible link wire, but I didn't... famous last words, perhaps.

I'm going to have to remember this. When I require my truck (one of these years), I want to go to an external shunt style ammeter to reduce the current flowing through the cluster.

I may need to mod Drew's kit for aftermarket gauges to take a +/-50A gauge.

 

[amaurer]

EDIT: Nevermind, my problem appear unrelated.

[STRIKE]QUOTE Rudi/Tom - its now many pages back, but I have remembered our ammeter playtime over these year... since I now have a battery that dies mysteriously, I was finally galvanized (ha, electrical pun!) to action.

I thought of all kinds of fancy methods for making shunts and eventually ignored them all and just went with 18" of coiled 14ga wire. I should have used fusible link wire, but I didn't... famous last words, perhaps.

Anyway, ammeter works great now, perhaps one of the first 1980+ cruiser ammeters in history to do so.

/QUOTE

DON'T DO THIS!! OH FOR THE LOVE OF GOD DON'T DO THIS!!

Let me paint you a picture...

So there you are, enjoying your functional ammeter. Birds are singing, the sun is shining, the needle is deflecting - all is well and good in the world. You've enjoyed nearly 500 miles of current-measuring bliss.

Then one day, your wife borrows your 40-series. Mind you, this is already a point of contention because its hard for her to drive without power steering and you've forced her to use it while you're repairing her truck. You charge the battery beforehand (since you suspect a voltage regulator problem has prevented it from charging properly) so she doesn't run into any problems.

Storm clouds begin to gather.

She drives around all day without troubles and you begin to think that maybe she has made peace with your truck after all these years and is beginning to appreciate it in all its road-tractory glory.

::Lightning flashes in the background::

Its evening now and your beautiful wife comes to pick you up from work. She idles in front of the building with her lights on waiting for you to come out.

The voltage regulator fails.

The ammeter dutifully reads -10A due to the headlights. You wife doesn't notice, or appreciate, what a glorious event this is.

One minute of waiting turns into five...

Hm.

Whats that smell, she wonders?

Suddenly, smoke begins to pour from the instrument cluster.

She frantically calls you, saying to get your ass outside immediately because "the steering wheel is on fire." You laugh, but this is exactly the wrong thing to do.

You reach the car and turn the lights off until you have high RPMs so that the ammeter will not read so low.

You drive home in silence. You are so very in trouble.

I'm not entirely sure I understand this yet. But that was my experience. Those 5A fuses are apparently not sufficient to prevent some dramatic overheating.[/STRIKE]

 

[John McVicker]

I have no tech to add, and I am truly sorry this happened...BUT... that is one funny post.

Thanks, John

 

[bj40green]

Hi Drew,

Sorry to hear that. Did you investigate what/where smoked/burned up?
So you're saying that the current was less than 5 Amp because the fuse(s) didn't blow but at the same time that current was too much for the wiring or the 3 pin connector on the back of the cluster. Right?

Hmmmmm,

Rudi

 

[amaurer]

Hi Drew,

Sorry to hear that. Did you investigate what/where smoked/burned up?
So you're saying that the current was less than 5 Amp because the fuse(s) didn't blow but at the same time that current was too much for the wiring or the 3 pin connector on the back of the cluster. Right?

Hmmmmm,

Rudi

I really don't know. I removed my shunt but something is still wrong under there... I tried out out again and the harness is a bit melted and the fuse panel started to melt.

I'll dig into it tomorrow. However I haven't done any electrical work in the last year apart from the shunt change, so this is highly suspicious.

 

[amaurer]

I've striked my post... my problem appears coincidental. The ammeter was in perfect shape, it was the wire between the headlamp switch and the tail lights that burned up??

I'll make a new post for that mess. As far as I know the shunt idea is still sound.

 

[Ming89FJ62]

don't forget the "golden rule" - never, never ever let your drive the 40

 

[bj40green]

Found the missing gauge cluster 9/72 - 9/73

I was always wondering why I couldn't find pictures of a '72 - '73 cluster.
Thanks to Mud member Sproggy we found it.
The front looks like a 3rd gen. cluster but the back looks like a 2nd gen. cluster.
Clearly this was the change over model from Sept. 1972 till Sept. 1973.
The cluster is technically a 3rd gen. cluster. Front and internals are identical to the 3rd gen. cluster.
The back side is a metal housing (2nd gen. style) but without the PCB (Printed Circuit Board) from the 3rd gen. clusters.

Have a look......

Note: the red arrow points to the ground terminal for the VR inside the Fuel gauge.

Rudi

 

[DTSkyCop]

Excellent info... Love this thread...

 

[sproggy]

'60s metal speedometer not dropping to zero

Rudi et al,

I've broken down a speedo/odo from an old cluster, cleaned it up, and put it back together. It's a second generation but the whole speedo/odo mechanism is metal, not plastic. I've seen two like this, now, and think they must be from the late 60s. Anybody have experience with these, know where/when they're from? Anyhow, all seems to be in order except the speedo doesn't reside at zero but at the 12 mph mark. It does bottom out correctly at zero when I move it with my finger so the needle is on in the right place, so it would appear. ...seems to be something to do with the weighted metal wheel inside the mechanism. Or perhaps once the speedo cable is hooked up this will bring it to zero (I kind of doubt that).
Any input?

Cheers, Sproggy

 

[bj40green]

Pull the needle and replace it at the 0 mark.
It won't go to the 0 mark when the cable is on.

Rudi

 

[sproggy]

...I could do that, but usually I put the needle at the zero mark when the speedo "bottoms out". It comes to rest at the "bottoming out" point, where it doesn't turn any more to the left.
Let me rephrase that: on this speedo, the "at rest" point and the "bottoming out" point (where the speedo won't turn any more to the left) are not the same point. I can put the needle on so it is pointing at zero when at rest but the speedo will at times go under zero, such as when going over bumps. This doesn't seem correct. It seems like the counter weight on the back end or spring or whatever cause the speedo to return to zero has lost its strength. Maybe I should open it up and take a look...

 

[bj40green]

Maybe I should open it up and take a look...

Be very, very, very careful when you open it up.
I keep my fingers crossed.....

Rudi

 

[watrob]

Could you point me in the right direction to trouble shoot the problem I am having with my amp meter in the standard fj40 cluster.


The cluster I have has a 3 pin plug connection for the amp meter (50 amp version). My 40 is a diesel with a external standard FJ regulator. The amp meter has never worked, it does not move to the negative or positive during motor start or general running of the motor. The alternator is fine and charges battery.


I have tried another cluster, same thing no amp meter readings, all other gauges in clusters work fine.


So where do the wires from the amp meter trace back to? all fuses in fuse holder are fine also. Volts come up on battery when engine is rev'd (checked with multimeter at battery)


All other electrical systems work fine, glow plugs, filter light, glow plug light, brake warning light etc, in other words there is no major wire loom problem such as fried wires.

Is my problem that the fusible link has blown and or one or two of the fuses in the little black plastic holder at the battery have blown? if these were blown then most things electrical would not work I thought, so I have dismissed this..... am I wrong in this because one of the fusible links goes directly to the amp meter?

Does the amp meter also connect thru its own fuse in the main fuse holder inside the cabin, some mention the engine fuse?

Or does my amp meter only move such a small amount I cannot see it move, would your fix the thread #301 above fix (wire coil connection) the problem? also I am having trouble working out where your connecting this wire coil too and what were the wires you cut?

Thanks

 

[Alstruck]

What I would do first is remove the cluster. But leave it hooked up. After making sure nothing is shorting turn on the key and see if you are getting voltage to the amp meter. Do not read across the gauge, but rather each post to ground.
I have an older 30 amp is mine us different. Unless you have big fat wires going to your amp meter you probably have a shunt between your amp meter and regulator. It sounds like a bad connection. You say you have 3 wires to the amp gauge. That's strange. Most amp gauges only have two wires. It shouldn't be that hard to fix if you have a schematic of your FJ.


1971 FJ40
1952 VW Split Bug
1997 Jaguar XK8

 

[watrob]

What I would do first is remove the cluster. But leave it hooked up. After making sure nothing is shorting turn on the key and see if you are getting voltage to the amp meter. Do not read across the gauge, but rather each post to ground.
I have an older 30 amp is mine us different. Unless you have big fat wires going to your amp meter you probably have a shunt between your amp meter and regulator. It sounds like a bad connection. You say you have 3 wires to the amp gauge. That's strange. Most amp gauges only have two wires. It shouldn't be that hard to fix if you have a schematic of your FJ.


1971 FJ40
1952 VW Split Bug
1997 Jaguar XK8

On the back of the cluster there is a 3 pin connector plug right behind the amp meter section, I would say 2 of these wires are for the amp meter.


I would have thought that there would be a normal fuse somewhere in the circuit but as I have read this circuit also goes thru the ignition switch, so does the engine fuse control the amp meter on a diesel?

One would assume that one wire comes from the regulator box (I have an external regulator) to the amp meter, then the second wire leaves the amp meter thru the ignition switch, thru a fuse in the cabin fuse holder (maybe), then onto the battery. By your method, by measuring these two wires if there is power with the ignition switch on then the connection to the battery is fine, no blown fuse, so that means the wire to alternator is broken.

If there is no power then the wire which goes thru the ignition switch to the battery is faulty?

 

[bj40green]

Could you point me in the right direction to trouble shoot the problem I am having with my amp meter in the standard fj40 cluster.


The cluster I have has a 3 pin plug connection for the amp meter (50 amp version). My 40 is a diesel with a external standard FJ regulator. The amp meter has never worked, it does not move to the negative or positive during motor start or general running of the motor. The alternator is fine and charges battery.


I have tried another cluster, same thing no amp meter readings, all other gauges in clusters work fine.


So where do the wires from the amp meter trace back to? all fuses in fuse holder are fine also. Volts come up on battery when engine is rev'd (checked with multimeter at battery)


All other electrical systems work fine, glow plugs, filter light, glow plug light, brake warning light etc, in other words there is no major wire loom problem such as fried wires.

Is my problem that the fusible link has blown and or one or two of the fuses in the little black plastic holder at the battery have blown? if these were blown then most things electrical would not work I thought, so I have dismissed this..... am I wrong in this because one of the fusible links goes directly to the amp meter?

Does the amp meter also connect thru its own fuse in the main fuse holder inside the cabin, some mention the engine fuse?

Or does my amp meter only move such a small amount I cannot see it move, would your fix the thread #301 above fix (wire coil connection) the problem? also I am having trouble working out where your connecting this wire coil too and what were the wires you cut?

Thanks

So you have a cluster with a 50-0-50 Ammeter, with a 3 prong connector on the back side, right?
That makes it a 4th generation ('79 and later) cluster.
As you can read earlier in this thread..... it didn't work from factory
See page #4 post #75 where it all started. There is a design error in this circuit.
But............... there is a solution
If you go to the top of this page post #301 you'll find that "Amaurer" found the solution to fix this problem.

Rudi

 

[Alstruck]

I'm guessing that if you changed the cluster and still no amp reading then you have a stunt. A stunt is a resister in your amp meter that only take a portion of your amps from the main cable from the battery. This allows a smaller wire to go to the amp meter and it allows your car to function if the amp meter burns out.
The 2 wires on the amp meter should voltage all the time. I don't have your schematic but most cars are wired the same. I'll bet neither leg has voltage. That means the wire from the main 12v wire from the battery to the amp meter is disconnected or broken. Now where that wire is, I haven't a clue.
But my first check would be to check the voltage on the amp meter. It should be 12v.


1971 FJ40
1952 VW Split Bug
1997 Jaguar XK8