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Discussion Starter · #1 ·
After totally rewiring this ford 3000 everything worked great ! Both the Fuel and Temp gages, and the oil pressure light. Well,,,,not for long! Both of the gages appear to be dead! I ran out of time and didn't get to check much but I've wondered for a while how the gage voltage stabilzer works. I have a white hot wire coming from the start switch and it has power when the switch is on. The wire goes to one side of the stabalizer and branches off to one side of the gen and oil pressure lights. The gen wire is disconnected as I now have alternator but the oil light functions perfectly. The other side of the stabilizer jumps to a post terminal on each gage with a grn wire. Finally, the other side of the gages run out to the temp & fuel tank gages. Whew!

So, if I'm getting 12V from the white wire, what would one expect to see on the gage side of the stabilizer? Can I check the stabilizer with a volt/ohm meter? Can I jump a hot to the gages to see if the prob is the stabilizer or will I fry my sensors? Thanks for any help :)
 

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You'll save yourself untold grief if you'll pick up a multi-meter for testing. If you think you might want to work on electronics (like auto computers & such), go ahead & pick up one with 10 mega-ohm impedance. Hop-Sing is cranking them out way cheap anymore. I have been told that the voltage stabilizer is only a rudimentary voltage regulator set at 10v. I can't verify that, never had call to measure one. Jump leads have their place, put then so do fire axes. Voltmeter would be my way to check. Most texts strongly caution against measuring resistance across solid-state circuitry. You're doin' good!
 

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1981 Ford 1100 4WD
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My only experience with Ford voltage stabilizers is with early Ford Mustang. The purpose was to get the gauges not to fluctuate as the voltage changed from 12 to maybe 14.5 (idle to highway speed). In later models they changed the gauge design so that a stabilizer was not necessary.

I don't know the stabilized voltage for the 3000, but 10volts sounds about right. Use a small test lamp or a multimeter on the gauge side of the stabilizer to make sure it still works.
 

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Discussion Starter · #4 · (Edited)
Thanks for the replies!

I did a quick check this morning and I am getting 12V to the input terminal of the voltage stabilizer (VS.) I also lifted the wire on the Fuel gage and it read the same voltage as the input to the VS.

I read 00.1 Ohms across the VS with both the wires lifted from both sides.

Seems like a the VS doesn't really have any resistance and I'm unsure of whats really inside that little box :) Could be a capacitor and an inductor??

Since I'm getting 12V to the Fuel gage terminal, I'm afraid the gages are fryed. They are both sitting on "zero." I don't remember but I think the voltage at the Fuel Gage fluctuated as I rev'd the engine. I wonder how much current I might expect to see going through those gages?

Any ideas?
 

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1981 Ford 1100 4WD
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The typical gauge was a bimetal design with a heater coil wrapped around the bimatal element. Sending a current thru the coil would heat the bimetal assembly. One metal would expand much more than the other, thus moving the needle. Sounds like the heater elements maybe fried. Was this a 6 volt to 12 volt conversion? Our was it at one time started with 24 volts?
 

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Discussion Starter · #6 ·
It's been a 12V with alternator for years. I just rewired the trtactor and hooked it all back the other day. The gages worked fine until last eve but not anymore. I too think they're bad now but would like to be reasonably certain before I spend whatever I have to for them to work. I also want to correct any problem so that I won't ruin the replacements.

I know I hooked them back up exactly as before but a new wire was ran to the Temp sensor. The fuel gage is the original wire.

Can I do a continuity test with a meter to see if they are opened or shorted?
or maybe take an inline current reading to see if they're opened?
 

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Discussion Starter · #7 ·
Well, for what ever its worth I read across the gages and read 60-70 ohms which should give a current of only 17 MA @ 12V. Now although I'm not sure if that's indicative of too much resistance and/or not enough current, but the things are getting 12V to the sending units. I now strongly suspect the gages are burnt up.

I'm gonna take the cluster apart just to see what's in there. Might be a bad move but what else to do?

Any more ideas are very welcomed !!!
 

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The vintage of your gauges makes it plenty safe to read their resistance, unlike the digital & other high-tech stuff common today. Your reported resistance sounds reasonable to me, especially for a bi-metal with heater type. If the heaters were crispy critters you'd see infinity for resistance. I suppose there could be a mechanical problem with the bi-metal units causing them to be inactive, but the electrical sounds reasonable.
 

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Discussion Starter · #9 · (Edited)
Thank you H-D :)

I thought it would be OK but it's always nice to have some comfirmation. And the resistance....I really didn't have a clue what was resonable.

:banghead3

Well I took the cluster apart and looked at the gages. neither the wire nor the element "looked" burnt and they certainly weren't fried. I did fiddle with the coil wires some with tweezers , reassembled them & hooked them up with a straight 12V's. The Fuel gage did slowly move over to full. The temp is still dead though.

I'm going to do an inline ampmeter test this eve and see if there's any ampereage going through in the temp circuit. One thing I did notice is that the coil wire on the temp gage is laying against the metal so I wonder if maybe it's shorting to ground some (leaking maybe.)

There's also quite alot of corrosion on the terminals going into the gages. But I was nervous about taking the gages completely out.

I have looked at buying a new cluster but the best price I've found is close to $200. I think I can install some sort of cheaper gages which I will have to mount externally. I really don't want to do that though.

Thanks for yall's help !
 

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Discussion Starter · #10 ·
Fixed 'em :) Nothin a little cleanin' didn't help :p
 
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