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Discussion Starter · #1 ·
Before I remove the instrument panel and check bulbs, just realised that the fuel gauge and clock are not working.
Hence, would this be an electrical issue? How many bulbs illuminate the instrument panel, does anyone know?
Thanks
Larry M
 

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The fuel gauge and clock are not on the same circuit,
The fuel gauge is on the same circuit as any other gauge. Most of the time fuel gauge issues are because the sender or sender float is bad.

Most of the time the clock does not work is because the re-wind points have burned. They have burned because the car battery was low a number of times.

I do not know exactly how many bulbs the instrument panel uses. As a guess it would be 4 to 6.

Action
 

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The fuel gauge and clock are not on the same circuit,
The fuel gauge is on the same circuit as any other gauge. Most of the time fuel gauge issues are because the sender or sender float is bad.

Most of the time the clock does not work is because the re-wind points have burned. They have burned because the car battery was low a number of times.

I do not know exactly how many bulbs the instrument panel uses. As a guess it would be 4 to 6.

Action
Thanks Action :), So I guess I would need a new clock then I supose? Sorry to show my ignorance Action but what is the "sender or sender float is bad"? How would I check that? Is that an electical voltage that's not being recevied?
Thanks Larry M
 

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The sender is in the tank.
An electrical signal comes from the gauge back to the sender. The sender has a variable resistance and back out to a ground. I did not view the vid. There are two wire lugs shown. One is in and the other is out to a ground.
Make sure there is a connection to the ground on one side.
Make sure there is power to the other lug. (From the gauge) The power may be less than 12 volts. Just don't remember.

Many times the float in the sender no longer floats. (It sinks) And when the float is at the bottom of the tank the gauge will read empty.

Action
 
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The sender is in the tank.
An electrical signal comes from the gauge back to the sender. The sender has a variable resistance and back out to a ground. I did not view the vid. There are two wire lugs shown. One is in and the other is out to a ground.
Make sure there is a connection to the ground on one side.
Make sure there is power to the other lug. (From the gauge) The power may be less than 12 volts. Just don't remember.

Many times the float in the sender no longer floats. (It sinks) And when the float is at the bottom of the tank the gauge will read empty.

Action
Thanks Action, as always :) much appreciated
 

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The fuel gauge and clock are not on the same circuit,
The fuel gauge is on the same circuit as any other gauge. Most of the time fuel gauge issues are because the sender or sender float is bad.

Most of the time the clock does not work is because the re-wind points have burned. They have burned because the car battery was low a number of times.

I do not know exactly how many bulbs the instrument panel uses. As a guess it would be 4 to 6.

Action
+1,

I would first check to make sure the voltage regulator for the fuel gauge is working first before messing with the sender as it's under the dash. The voltage regulator crudely regulates by switching B+ on and off rather quickly giving a rough 5 volts if you integrate the area of the voltage of time spent on with respect to total time of one cycle or the period. In other words it's just a really fast flashing thermal turn signal flasher type device. This rough 5 volt output is what powers the fuel gauge. So the fuel gauge gets this "regulated" +5V on one terminal and the other terminal goes to a variable resistor in the fuel tank that's connect to a float that rides on the level of fuel. The other end of the variable resistor or in this case a rheostat is grounded (behind the back seat) to complete the fuel gauge circuit. Measuring resistance of the sender should yield, If I remember right, 10 ohms is full, 73 ohms is empty and 23 ohms is half full or half empty depending on your point of view of the world.

A couple quick checks for the fuel level gauge is check for the +5 volts on one terminal of the fuel gauge, if you have that, then unplug the electrical connector at the fuel tank and ground the wire going to the sender in the plug, that should cause the fuel gauge to read past "F"ull. If that happens it's a pretty good guess the gauge and the wiring is good up to that point and the problem lies within the sender inside the fuel tank. However it doesn't mean the fuel gauge is accurate.

The best way to test for true accuracy of the gauge is buy the 3 resistors I noted (a 10, 23, and 73 ohm 5 watt) and sub each one in at the connector normally on the tank and see what the fuel gauge reads. If you look really closely at the fuel gauge above the letters F and E there are two tiny dots. When substituting the fixed resistor(s) in place for Empty and Full the needle should be within the two dots or resting on one of them depending on which resistor is substituted. And of course the meter should read half for the 23 ohm and there are no calibration marks for that, but is rather a gross calibration check.

Just a note on the sender (variable resistor/rheostat) inside the tank. If it's found to be at fault, you may wish to look for a good used one or an NOS one. The reproductions are terrible as I bought one a couple years back.

On the topic of the dash lights. Have you tried to turn the headlamp switch with the parking/running lamps on or headlamps on? That dims the dash lights and also turns on the dome lamp if rotated all the way to the left. That also is a rheostat and the contacts get dirty to dim the dash lamps. There is a 3 amp stubby fuse in the fuse block that feeds the dash lamps, check that to make sure it's not blown or has dirty contacts. Again that fuse only gets power if the headlamp switch is pulled out 1 or 2 notches (parking/running lamps or headlamps position) and with the knob turned all the way to the left just before the detent that turns on the interior lamps.

The clock is most likely exactly what Action pointed out. It could also be on rare occasion that it has truly blown off the contacts off the rewind coil by normal long running. Every 20-40 seconds the rewind mechanism activates on these old clocks and it's a high current short duration pulse that slaps the mainspring to wind a little. Since it's just a big solenoid on a set of points and Ford chose not to use a capacitor or diode across the points they arc rather severely every time (20-40 seconds) the rewind is called for use. This blows minute chunks of points away every time and eventually there's nothing left.

You have a couple of choices when it comes to the clock. You can try to find an NOS one and just see if it works, but an NOS one will probably be 100-300 dollars and is still a gamble as it's NOS and all the lube is dried out in it. Even if it does work it will erode the points unless a diode is placed across the points in reverse bias to act a free wheeling diode and alleviate the arcing. This takes a little skill with soldering to achieve (been there done that). Or your last choice is to send your clock out for a quartz conversion. This is also pretty pricey but if done right will last a lifetime. I did a unique quartz conversion on my 1973 Chevrolet full size cars' clock over 20 years ago and it's still working to this day keeping perfect time. I cannot vouch for others work so do your research before you commit to a particular service.

Hope that helps a little.

Cheers
 

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^^ All the best detail.

Does that model year only have a fuel gauge?
If there are other gauges (coolant) and that other gauge works, the IVR and instrument panel gauges should be good.

Action
 

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^^ All the best detail.

Does that model year only have a fuel gauge?
If there are other gauges (coolant) and that other gauge works, the IVR and instrument panel gauges should be good.

Action
HI Action,

65-68 full size Fords only use the fuel gauge and is the only the load on the regulator. I believe the Mercury's have a coolant gauge.

Cheers
 

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Not sure about 67 Merc as the instrument panel was redesigned in 67 to be smaller.
My 66 Park Lane has fuel, coolant, oil and amp gauges.

Action
 

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Discussion Starter · #11 ·
+1,

I would first check to make sure the voltage regulator for the fuel gauge is working first before messing with the sender as it's under the dash. The voltage regulator crudely regulates by switching B+ on and off rather quickly giving a rough 5 volts if you integrate the area of the voltage of time spent on with respect to total time of one cycle or the period. In other words it's just a really fast flashing thermal turn signal flasher type device. This rough 5 volt output is what powers the fuel gauge. So the fuel gauge gets this "regulated" +5V on one terminal and the other terminal goes to a variable resistor in the fuel tank that's connect to a float that rides on the level of fuel. The other end of the variable resistor or in this case a rheostat is grounded (behind the back seat) to complete the fuel gauge circuit. Measuring resistance of the sender should yield, If I remember right, 10 ohms is full, 73 ohms is empty and 23 ohms is half full or half empty depending on your point of view of the world.

A couple quick checks for the fuel level gauge is check for the +5 volts on one terminal of the fuel gauge, if you have that, then unplug the electrical connector at the fuel tank and ground the wire going to the sender in the plug, that should cause the fuel gauge to read past "F"ull. If that happens it's a pretty good guess the gauge and the wiring is good up to that point and the problem lies within the sender inside the fuel tank. However it doesn't mean the fuel gauge is accurate.

The best way to test for true accuracy of the gauge is buy the 3 resistors I noted (a 10, 23, and 73 ohm 5 watt) and sub each one in at the connector normally on the tank and see what the fuel gauge reads. If you look really closely at the fuel gauge above the letters F and E there are two tiny dots. When substituting the fixed resistor(s) in place for Empty and Full the needle should be within the two dots or resting on one of them depending on which resistor is substituted. And of course the meter should read half for the 23 ohm and there are no calibration marks for that, but is rather a gross calibration check.

Just a note on the sender (variable resistor/rheostat) inside the tank. If it's found to be at fault, you may wish to look for a good used one or an NOS one. The reproductions are terrible as I bought one a couple years back.

On the topic of the dash lights. Have you tried to turn the headlamp switch with the parking/running lamps on or headlamps on? That dims the dash lights and also turns on the dome lamp if rotated all the way to the left. That also is a rheostat and the contacts get dirty to dim the dash lamps. There is a 3 amp stubby fuse in the fuse block that feeds the dash lamps, check that to make sure it's not blown or has dirty contacts. Again that fuse only gets power if the headlamp switch is pulled out 1 or 2 notches (parking/running lamps or headlamps position) and with the knob turned all the way to the left just before the detent that turns on the interior lamps.

The clock is most likely exactly what Action pointed out. It could also be on rare occasion that it has truly blown off the contacts off the rewind coil by normal long running. Every 20-40 seconds the rewind mechanism activates on these old clocks and it's a high current short duration pulse that slaps the mainspring to wind a little. Since it's just a big solenoid on a set of points and Ford chose not to use a capacitor or diode across the points they arc rather severely every time (20-40 seconds) the rewind is called for use. This blows minute chunks of points away every time and eventually there's nothing left.

You have a couple of choices when it comes to the clock. You can try to find an NOS one and just see if it works, but an NOS one will probably be 100-300 dollars and is still a gamble as it's NOS and all the lube is dried out in it. Even if it does work it will erode the points unless a diode is placed across the points in reverse bias to act a free wheeling diode and alleviate the arcing. This takes a little skill with soldering to achieve (been there done that). Or your last choice is to send your clock out for a quartz conversion. This is also pretty pricey but if done right will last a lifetime. I did a unique quartz conversion on my 1973 Chevrolet full size cars' clock over 20 years ago and it's still working to this day keeping perfect time. I cannot vouch for others work so do your research before you commit to a particular service.

Hope that helps a little.

Cheers
WOW thanks so much For the information. I've tried the fuse for dash lamps and no good. Also headlights are on and turned but still no instruments lights. I'll have to take it to a car mechanic though, I don't have any expertise to troubleshoot the electrical problems.
However very useful, thanks again 🙂
 

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Many mechanic are not familiar with that vintage of a ride will burn up a lot of your cash learning the repair first.

It maybe that all of the light bulbs are burned out. The worst case would be a bad printed circuit.

Action
 

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Many mechanic are not familiar with that vintage of a ride will burn up a lot of your cash learning the repair first.

It maybe that all of the light bulbs are burned out. The worst case would be a bad printed circuit.

Action
Hi Action,

There's no printed circuit boards on the full size Ford 1965-68 in the dash. It's all socketed bulbs with wires. The 65/66/68 are bayonet bulbs. I would imagine the 67 is also. It's really simple with a wad of wiring.

+1 to the modern mechanics trying to figure out your old car now-a-days. Most shops will not even touch a car more than 20 years old. There are specialty shops that deal with just old cars however most have a different business model. It's pay up front first for an estimated amount of time. If they finish before that time your remainder is refunded. If they burn through that time, works stops until another infusion of cash is received. This may sound unfair to the uninitiated, but with an old car, anything and everything can go wrong, then add in sorting out 50 years of modifications and previous bad repairs plus countless hours of research on parts and believe me it's more than fair. It would not be uncommon for a brake job to reach a grand because of well, someone put a different braking system on it from X car and it might take 3-5 hours just to figure what brakes are on the car. You can see how this avenue will consume more cash than the car will ever possibly be worth.

Unless your extremely well off, never take an old car in for repair, learn to do it yourself or get rid of the car. It's a harsh reality most people end up learning the hard way.

I would strongly suggest if you have not done so to buy the 1967 Ford Service Manual and I don't mean Haynes or Chiltons, god those are such crap. Then study that Ford Service Manual as if you were to be tested on it, because in a way you will be when you work on your car.

Rant to ensue:

In general it befuddles me on why so many people do not want to buy the service manual for their vehicle. It hurts my brain to an Nth degree on why so many people make a repair sooooo much more incredibly harder than it has to be. I consider my time valuable and so I want the information to make the repair as quickly as possible and move on with other projects.

Rant over :)

The dash lighting is pretty easy to figure out. All you need is some initiative, the manual, a test light and time to devote to it.

Cheers
 

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In general it befuddles me on why so many people do not want to buy the service manual for their vehicle. It hurts my brain to an Nth degree on why so many people make a repair sooooo much more incredibly harder than it has to be. I consider my time valuable and so I want the information to make the repair as quickly as possible and move on with other projects.

Cheers
I have the same befuddlement. (if that is a word) Some years the shop manual is so low cost.
Yet they go to a youtube vid where the out of focus camera is showing a tutorial on a related car (not actual model) with a dog backing in the back ground so loud it is difficult to understand what the guy from the Eastern Bloc country is saying.

With a shop manual it is in writing by comapny that designed and built the vehicle. Is it perfect. Nope. But it is pretty damn good.

Action
 

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Discussion Starter · #17 ·
I have the same befuddlement. (if that is a word) Some years the shop manual is so low cost.
Yet they go to a youtube vid where the out of focus camera is showing a tutorial on a related car (not actual model) with a dog backing in the back ground so loud it is difficult to understand what the guy from the Eastern Bloc country is saying.

With a shop manual it is in writing by comapny that designed and built the vehicle. Is it perfect. Nope. But it is pretty damn good.

Action
Thanks Action and Desert XL, will do for sure, I will buy a manual today
Thanks
Larry M
 

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There are some shops that can still fix older vehicles. I found a shop where the owner used to build and race cars and he has a good basic knowledge of the older vehicles. There are also younger mechanics who like classic cars and can fix them. Check around before you give up.
 

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Thank all of you for the great input. I, too, have dash light problems with 65 Gal convertible. After checking the fuse, then replacing one of the four dash bulbs (bought a bulb pack of varying sizes) I also still do not have any dash illumination despite having interior lights. Oddly, the high beam indicator and turn signal lights in dash do work, so safe to assume on a different circuit. I think my problem lies in the harness itself. Why? - idiot mechanic at a formerly reliable old car specialist caused a near fire in the dash when he routed the hot for choke on new intake manifold, through the accelerator cable hole on the firewall (guessing it was "easier" because lower on the firewall than the accessories through-hole about 6" higher - damn fool). I did not notice because I didn't inspect the work before leaving shop (my mistake) as these guys had done stellar work before. But this guy was new to the outfit. I digress: Didn't take long for the wire to ground in non-grommeted hole. Dash smoking 'n all that. No dash lights since. So, after I repaired most of the damage, fitted a new wire through the correct, grommeted loom hole, all was well with MOST of it .... I am going to have to source NOS harness and re-wire to correct. Idiot no longer working at that garage - he has cost me thousands and they ripped up about $500 labor bill. So far, idiot did the above, destroyed a steering rag joint (cranking on power steering while engine not running), then broke the horn ring trying to prove he installed new contact spring after turn signal cam replacement (had the NOS plastic bag with contact spring he had left on floorboard), and .... drum role .... spun a main bearing due to oil loss when he replaced the oil breather caps with solid, unvented ones causing crankcase pressure to skyrocket and spit the dipstick as well as 2 qts of oil in less than 5 miles. Unfortunately, or fortunately, oil did not hit headers but gushed all over fender wall and down, so no smoking. I had top down so oil smell didn't catch up with my nose till I slowed down. Too late ... I couldn't get her stopped fast enough. I pulled over quickly but damage already done. I was going to get a rebuild anyway but not that day. So this guy, pretending to be a mechanic, took every shortcut he could. Owner of shop whom I consider a friend, ripped up bill and moaned about all the experienced guys aging out with lunkheads like this trying to fill that void. Then, he said he wouldn't blame me if I didn't come back. I took heed of his wisdom. His business is buying, restoring and selling classics. Maybe not for long. Sorry for the tome. Action and DesertXL are correct: Get the shop manual (I have) - you will make mistakes, but not like I did. Each mistake is a learning opportunity - I got mine in spades.
 
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