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1976 416.141
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350 Posts
Discussion Starter #1
Folks, what's the easiest way (is there an easy way) to get to the combined instrument gauge on a 406/416? Through the doghouse? From the hood? Do I need to remove the fuse block? I've got a intermittant Ladikontr light and I need to get up in there.
Thanks
Rick
 

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78 406
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251 Posts
OK you got me, what is a Ladikontr? Just reach around from the dog house. The biggest pain is the air line hookup for the air pressure gauge. Might as well put all the bulbs in, especially the alternator one, if that one doesn't work you get no charging.I clean all the contacts and put silicone dielectric grease on them to stop future corrosion. If you want to open up the gauge to clean it inside you need to pry the lip from the backside of the bezel all the way around carefully and the bezel will come off the front with the glass. Anybody found LED crossovers for the dash illumination. I don't think it would work on the charging lamp, but the rest would benefit I think. Don't forget to put the brown ground wire back on the gauge mounting stud when reinstalling. Also bleed the air tank down before removing the air line.
 

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1976 416.141
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350 Posts
Discussion Starter #4
G-66 and Tructor, Thanks, What actualy holds the cluster to the dash? nuts, bolts, screws? Did I see thumbscrews on the backside PDF? Do I have to disconnect the wires and air line before pulling the cluster or can I unscrew the nut/bolts/screw/thumbscrews and pull the cluster out into the cab a few inches and then remove wires and hose?
Thanks
rick
 

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68 Posts
There's a U shaped bracket (bridge clamp) behind the meter assembly that pulls the meter down into its hole in the dash. There are indeed 2 thumb nuts threaded onto studs protruding from the meter housing that are used to put clamping effort onto the U clamp.

As described earlier, loosening the air lines is the worst of it. The wires are on a multi-pin connector and once the connector, air lines and thumb nuts are off, the meter comes up out of its hole.

You will access the meter removal from ALL directions, but mostly after clearing the hand space under the hood.

By all means follow the advise and make the meter lighting functions perfect before reassembly. Clean the glass face and put it together like you mean it.

Best regards,

Rick
 

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U-406/416
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687 Posts
Hi Im working on my gages today, putting in a new speedo, and also new LED lights all over.

The Two main dash lights use Ba9s bulbs x2 and x5, and the middle tacho uses only one ba7s, in case anyone wants to get bulbs from a auto parts store.

The main muti gage and tacho, is working great and lights up bright with the LED's.

As far as the outer 4 bulbs, do they only turn on for example when that function is be operated? example the Hi-beam...?

Its says something above on here that if the charge light is swiched out for LED or not working the truck wont charge, Is that true?

Last qestion the new Speedo gage is not lighting up even with new factory bulbs. When I check the four prong plug with a muti meter, only one wire the "red" on is providing 12V, what do the other three do, I see two are connected together?

How is the Speedo gage grounded
 

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U1000Ag
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2,296 Posts
Indeed - the charge light actually provides the start-up current for the field coil. So, installing a LED may well result in the alternator not charging. You need to install a suitable resistor in parallel with the LED - I would stick with the regular bulb as it only draws current when not charging. Keep it simple.
 

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U-406/416
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687 Posts
Ok thanks,

Anyone know? where do the other three wires on the speedo go, Im only getting power on one "red" and the gage is new and none of the bulb I tryed seem to work?
 

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406 1973 & 2010 1952
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87 Posts
On mine the original black wire from fuse 12 ( permanent 12v) has been extended with red.
The striped wire is from fuse 10 which is powered from the ignition switch.
The other two are ground.
The red light comes on when power is applied and there is no tachograph disk inserted.
Hope my home made diagram helps.

Mike
 

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U-406/416
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687 Posts
Thanks very much, that helps allot!

I have to switch out some fuses tommrow and I will keep, updateing things till I can post a few pics of the dash all lite up at night.
 

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'78 Mog 416.141 DoKa
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3,406 Posts
FYI - if your alternator charge light burns out, possibly the first indication is no tachometer reading (since the excitation for the tach comes from the alternator). You CAN start the alternator charging if you give it higher revs. I guess the increase in speed will generate a little self-excitation and get current flowing.
 

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Hmm, I replaceds some fuses, and now my my red wire has 12v again, but the with with red strip dose not.

When I try to jump power from the two togther, my plug socket fuse blows. Then I tryed something elseand my right tail fuse poped?

It's kinda frustrating, I might just have to get a electrition to check it out, New gage new lights and she dont go damb. All the other gages and small lights are working, Maybe its just the NOS 419see gage is ment for 24V
 

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U-406/416
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687 Posts
Getting close, I just poped out the other big speedo because it is still not working, best to bench test it and go on from there.

I still find it strange that it has two grounds that are looped together, and two seperate powers even though the gage really only has on function being the lights.
 

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1985 416 DOKA mid-mounted Rotzler winch, 1984 U1200AG
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443 Posts
Snow mogg,

Did you ever get your speedo working? (I have a SEE Speedo that I am planning on installing in my truck)

And for the BA9 and BA7 lights did you go with all white LEDs?

Assume for the charging bulb you left it incandesant?

I can not see my turn signal light at all....except after dark was thinking the LEDs would help me out.

Thanks ahead!
 

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1985 416 DOKA mid-mounted Rotzler winch, 1984 U1200AG
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443 Posts
Update to dash LED lighting..

On my truck there are (12V system with fairly new instrument cluster):

2 X BA9s in the MPH speedo that I got NOS to replace my tachograph. I used red LEDs they work great and look good.

1 X BA7 in Tachometer I do not have a red one for that yet but the white one is working fine.

The instrument cluster uses: (I do not have any LEDs for this yet)

2 X 168 bulbs for background illumination

4 X 168 bulbs to operate the indicator lights blinker, trailer blinker, high beam and charging.

I am going to leave the charging bulb and high beam bulbs alone since I can see those fine.

I am going to switch the blinker indicator over to the brightest LED I can find and see how that works.
 

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'78 Mog 416.141 DoKa
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3,406 Posts
The charging light needs to remain incandescent. The charging circuit depends on the current flow through the bulb to operate properly. Converting that light to LED would require a much more complex circuit then just a LED and resistor.
 

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1985 416 DOKA mid-mounted Rotzler winch, 1984 U1200AG
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443 Posts
I am going to leave the charging light alone and in it's incandescent glory. :)
 

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1985 416 DOKA mid-mounted Rotzler winch, 1984 U1200AG
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443 Posts
I suppose this is the best place to post this question…

I have problems with my temperature gauge here are the symptoms:

-Cold engine turn key on temp pegs beyond to 110C
-After running for a while up to operating temperature the gauge will come down to 70C (I can sometime accelerate getting a good reading by rapping sharply on the gauge) Then as long as the truck does not completely cool off the gauge seems to work correctly.

Has anyone else had this problem? I have had the instrument gauge out and have not seen any damage. Any advice short of buying a new instrument gauge?

Thanks ahead
 
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