1966 Custom Cab Gauges

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Sep 20, 2018 | 12:06 PM

#16

TA455HO

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From: Seattle

Here's a picture of my old MR-1 viewer. I put in a fiche card for my 1985 Toyota Celica and I can see if well enough, but it is only 16 frames wide by 13 high - maximum of 208 images - whereas these Ford ones are - best as I can count so far - 70 frames wide by 27 high - maximum of 1,890 images! Mine has no zoom beyond the default so I went with a more modern approach. I hope it works!

Chad

Sep 20, 2018 | 12:22 PM

#17

RattyFord

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From: Northern Colorado

NumberDummy,
Thanks for the info. I'll try to pull a few from some yard cars. Any way to test these without running volts through? I won't be able to power them at the yard, and the old man might not let them go for pennies on the dollar.

Sep 20, 2018 | 12:28 PM

#18

TA455HO

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From: Seattle

Quote:

Originally Posted by RattyFord

Need volts to test as far as I know. There is a bi-metal spring inside that heats up as current passes through it, but this deflects the spring and causes it to break connection so current stops and the spring begins to cool back down and then makes connection again, lather, rinse, repeat. It happens fairly quickly so when you put 12 volts to it you get a bit of a wobbly but much lower voltage that averages out to around 5 volts. The gauges, in turn, are slow reacting gauges so they see a fairly constant supply voltage coming from the ICVR and their display is fairly steady.

Chad

Sep 20, 2018 | 01:13 PM

#19

TA455HO

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From: Seattle

CONSTANT VOLTAGE REGULATOR TEST

Turn the ignition switch on. Check for voltage at the gauge feed wire (black with green stripe) at one of the gauges. The voltage should oscillate between zero and 10 volts. If it does not, the constant voltage regulator is defective, or there is a short to ground between the voltage regulator and the gauges.

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Simple way to eliminate shorts being a possible issue is to remove the ICVR and bench test it using a DC regulated power supply or a 12V battery.

Chad

Sep 20, 2018 | 01:56 PM

#20

RattyFord

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From: Northern Colorado

Yeah that's where I'm headed with the one I have. I suppose the old man at the yard might let me try them out on my truck's battery with some little jumper wires.

Sep 24, 2018 | 12:50 PM

#21

RattyFord

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From: Northern Colorado

So I got out to the yard and pulled a few constant voltage units that appeared serviceable. Turns out they weren't lol. I installed each one to give it a try and each one let out a bit of smoke... seemed like a good indicator of bad function, along with the fact that the gauges didn't power up. I pulled a few open and found some interesting results. All in all it was an interesting experiment, but I ended up ordering a new unit from Mac's.

I also had time to play with the odometer/speedometer and was able to roll back to match miles on my rebuilt engine. Much more useful than the "Beyond mechanical limits" that I was previously displaying. I plan to have the whole unit fully working this week... we'll see.

After all that, I got all my lights inside and out working properly and got the right oil pressure sender installed. Lastly, I'm repainting the gauge bezel and repaired some cracks with 2 part epoxy on the back side. All in all it should be drastically better than before.

Thanks for all the help!
Mike