The CV regulator on my '67 F250 has this little gadget piggybacked onto it and looks factory. I can make out FOMOCO on the broken insulation around the copper wiring wrapped around a tiny piece of what looks like an old amplifier turret board and it plugs onto the right side of the regulator. I cannot find what looks like a complete part number.

This item's turret board piece was broken when I got the truck last month but the gauges (with the exception of the fuel gauge) worked fine so I assumed the thin copper wiring was intact. I had the cluster out yesterday and must have bumped this piece when I reached in to d/c the speedo cable and it has now completely broken free of the regulator. None of my gauges work now which comes as no surprise.....

Question is, what is this item? Does it further drop voltage (looks like a hand wound resistor or voltage drop device to me) prior to the regulator? Is it necessary or can I bypass it and attach the lead directly to the regulator?

 

There is lower voltage going to the gauges. Not sure of the name but I do believe that is the inst cluster voltage regulator.

I think they are available in some of the catalogs and probably from some of the FTE sponsors as well.

 

They are available. I'm talking about the extra little thing attached to the back that I don't see on replacement units. I can take it off but should I....?

Where is NumbersDummy.....

 

C6DZ-10804-A .. ICVR ~ Instrument Cluster Voltage Regulator (Motorcraft GR-510) / Available from autoparts stores-take the original with you to match it up.

Applications: 1967/69 F100/750 / 1969 Econoline / 1970/72 F500/750 // 1966/68 Falcon/Fairlane/Torino/Comet / 1967/68 Galaxie/LTD/Mustang/Cougar.
-------------------------------------------------------------------------------------------------------------------------------------------------
C3MY-18A952-A .. Radio Suppression Choke Resistor-Attaches to ICVR / Obsolete

Applications: 1963/66 F100/1100 / 1967/69 F100/750 // 1963/66 Thunderbird / 1963/69 Galaxie/LTD / 1971/77 Bronco.

JST AUTOMOTIVE in Lebanon TN has 2 = 615-443-3086.

HASELDEN BROTHERS in Hemingway SC has 3 = 843-558-2134.

KLIMESH MOTOR SALES in Calmar IA has 3 = 563-562=3241.

CARPENTER NOS OBSOLETE PARTS in Concord NC has 14 = 800-476-9653.

Battleship USS IOWA now located in the Port of Los Angeles (San Pedro-berth 87), opens to the public 7/7/2012 as an interactive museum.

 

That's what i was looking for Sir. Thank you...!

It doesn't sound essential. Can I do without it? Whether it is essential or not is this part still available....?

 

See post 4, located 22 of the little charmers.

 

Oh I see.... Didn't read carefully enough....

ND, do you know if this part is essential for proper gauge function or is it an add-on to supress possible radio interference?

Thanks.

 

1 edited in the sources while you were reading it carefully.

 

Well thank you Sir. I have a call in to Klimesh and they are checking inventory.

Thanks again.

I am also wondering if some of the modern clip on ones will work in this application. They are about dirt cheap. Will try it without as well and see what happens. I expect interference will make the gauges act up. Will know before long....

 

your gonna fry your sensors

 

From the electronics perspective, yes, it or something like it is going to be needed. There are some other options, and can enhance things.

This item is just a simple winding of wire, sometimes on a 9v Battery terminal connection. It serves as a resistor since it is fine wire, but it is a "Choke". That means it is a coil of wire, which blocks a sudden inrush of current, and it smooths the current through it. Without it, the mechanical voltage regulator (ICVR) gets "shocked" with surges.

The windings in the instruments are designed to work at lower volts (5v) so that when the system voltage is low (11-12v) your instruments still work. So, that is why this circuit is at a lower voltage than everything else.

I said there were options. One is to wind your own replacement with transformer or magnet wire. But test the one you have now and see if the resistance (ohms) are correct. (value?) If you just need to replace the insulation, use cheap shrink-tube.

Another is to use a homemade voltage regulator, if you are handy with a soldering gun.

Here's a part of the previous thread:

.. home-made voltage regulator still works years later. This does an inexpensive job of replacing the CVR on the back of the dash cluster.

See https://www.ford-trucks.com/user_gall...&albumid=23629
gallery for pictures and the schematic. I made mine with a 9v battery terminal, so I could remove it if needed.

EXTRA: I agree with ... adding a Transorb or TVS (P6KE18A) to protect the circuit, and a diode is always good. This is a common circuit on the internet with schematics available. (Look up 5 volt voltage regulator LM...) There are only a few parts,....

Reading up on Transorb(s) (TVS, TransZorb, snubbers, etc.) might be good for anyone interested in zap-proofing their vehicle. Especially if you want to plug in fancy new devices. This is a great place to put one.

Hope that helps more than confuses!

 

Thanks for the encouragement 1972.... I had actually already begun a repair on this piece yesterday.... Figured I'd chronicle here later but why wait?

I have already epoxied the turret board piece as can be seen. I checked resistance prior which measured about 2 ohms and was constant so I figured the winding was intact. I need to unwind one wrap to lend enough wire to re solder to the one terminal and then, as you mentioned, slide a piece of heat shrink over it all. The 3/8" I have doesn't fit and I have to drive by a Fry's electronic store in the am so it was on my shopping list. Will let you know how it turns out.

Now, if I could only figure out why the fuel gauge doesn't work I'd be set.....

 

Your truck has two fuel tanks, in-cab & factory installed optional auxillary tank.

When you switch the tanks using the selector valve on the floor, then flip the underdash toggle switch that only changes the gauge from one tank to another, what happens?

It could be a defective dash gauge, but the following is the usual reason, and this is "an old old story."

The sending unit float is made from two pieces of copper soldered together. Solder breaks down, gas seeps in, float settles to the bottom of the tank.

Flip the seat forward, remove the sender from the in-cab tank, unhook the float from its crooked arm, and shake it. Hear any gas sloshing around?

COAZ-9202-B .. Fuel Sending Unit Float / Available from Ford.

Applications ALL: 1957/79 Passenger Cars/Trucks, 1961/79 Econolines & 1966/79 Bronco's.

 

I'll check that out ND. I did try the toggle with no result. the aux tank had been removed by the original owner and I wonder if I need to check anything in that wiring.... Doubtful, but I still wonder.

I did check impedance at the sender. Full tank showed about 18 ohms resistance. A couple of days later I found an article discussing fuel tank sender impedance. What I read suggested 18 ohms would be about normal for a full tank, and the resistance should rise as the tank empties. I figured I'd just drive it a bit and check it after about 150 miles to see if I got a reading higher than 18 ohms. If so I was going to assume the sender was working correctly. I'll look for that information....

edit: It was here at Fordification....

Fuel Tank Sending Unit Tech - FORDification.com

 

I just went out and checked it now. After about 150 miles (approx) resistance is 46 ohms. I think the sender is okay.