1978 F 100 instrument cluster help

[JBMCQ]

OK so my instrument cluster backing turned to dust like a vampire stuck with a wooden stake. What they didn't make plastic in 1978.
Pulled the Inst Cluster. The gauges were not working after intermittent -on again off again. So I want to test the components.
I have both an old school good quality analog Tandy meter and a newer digital one I'll be using for tests.

1- Where best to get a replacement backing.
I noticed whole clusters on e-bay ,how risky is it that one of the used ones will turn to dust in transit or shortly after I install it. I live in the desert southwest/ Tucson.
My trucks been here since 79. so mine lasted all that time.
A California used parts place has several + 1 in the mid west ,
would those tend to be in better or worse condition than being in our dry heat ?
Or what other options would be best ?

2- How to test the plastic circuit board / Check for continuity from point a to b ?
Does anyone have a picture of how it mounts in the backing ? as I said mine came out as dust.
How does the multiple power connector plug into the board? Are there locking clips in the backing that it attaches to ?
See the picture of mine - 1 of the copper contacts where the connector plus in is just starting to get loose,
it's the one on the bottom right end. Is this a problem or potential one ?




3- Testing the ICVR ,my understanding is 12v in 5v or is it 5.5 v out.
On the (it looks like the plug on a 9V radio 1 small contact 1- large one ) which is input / output.
If replacement needed what are my options ?

4- While I have it out should I just replace all the bulbs? Are they reasonable $$ ? No I'm not wealthy ,thanks for asking.

Anyway thanks much for any help , I have already drank a toast for your assistance.
No I don't have a drinking problem. Only problem is being able to afford my Scotch habit !
I have to leave enough for the damn light bulbs.

Regards,
Jim M

 

[fatherdoug]

As far as the backing plate goes, replacements can be ordered that are a different style plastic. They can be had at several websites(broncograveyard, etc) for about $70. Another member on this site (BKW) has stated that different plastic was used on some of the later E-series vans that are interchangeable. Using the same plate from older trucks will only provide some short-term relief, if you can find one in decent shape.

 

[thadleybaxter]

dash cluster

OK so my instrument cluster backing turned to dust like a vampire stuck with a wooden stake. What they didn't make plastic in 1978.
Pulled the Inst Cluster. The gauges were not working after intermittent -on again off again. So I want to test the components.
I have both an old school good quality analog Tandy meter and a newer digital one I'll be using for tests.

1- Where best to get a replacement backing.
I noticed whole clusters on e-bay ,how risky is it that one of the used ones will turn to dust in transit or shortly after I install it. I live in the desert southwest/ Tucson.
My trucks been here since 79. so mine lasted all that time.
A California used parts place has several + 1 in the mid west ,
would those tend to be in better or worse condition than being in our dry heat ?
Or what other options would be best ?

2- How to test the plastic circuit board / Check for continuity from point a to b ?
Does anyone have a picture of how it mounts in the backing ? as I said mine came out as dust.
How does the multiple power connector plug into the board? Are there locking clips in the backing that it attaches to ?
See the picture of mine - 1 of the copper contacts where the connector plus in is just starting to get loose,
it's the one on the bottom right end. Is this a problem or potential one ?




3- Testing the ICVR ,my understanding is 12v in 5v or is it 5.5 v out.
On the (it looks like the plug on a 9V radio 1 small contact 1- large one ) which is input / output.
If replacement needed what are my options ?

4- While I have it out should I just replace all the bulbs? Are they reasonable $$ ? No I'm not wealthy ,thanks for asking.

Anyway thanks much for any help , I have already drank a toast for your assistance.
No I don't have a drinking problem. Only problem is being able to afford my Scotch habit !
I have to leave enough for the damn light bulbs.

Regards,
Jim M

Jim, I live near Prescott, and I've been searching the local boneyard for parts...I ran across more than a few good clusters up here, FYI...

 

[73f250]

Got a another question to this one regarding gages for 73-79. where can I get new replacement gages. My wiring burnt from volt. reg. to the amp gage

 

[sgarver]

When I had mine out I decided to change all the bulbs. When I got to the counter at Advance Auto with a pile of blister packs, the counter guy said they had bulk packs that they keep for the local shops. I think it was less than 2 bucks for a pack of 10 or 12.
Today I pulled 2 78-79 gauge instrument panels at my local yard to see if I could swap out my idiot light panel. Both had great backs (North Ga) but the plug is different from mine. I had heard that they were different but had to see for myself. Anyway, I believe that good used original instrument panels can be had outside of the desert south west. Having said that, I wouldn't hesitate to buy one and expect it to last for many, many years here. Where your at, an old original may not last nearly as long.
As far as testing your gauges, no help here. Still learning these trucks as I go.

 

[BuzzGun79]

73,it might have shorted out the circuit board on the rear of the cluster & the actual guage may still be good.i dont see any guages available in my N.P.D.,LMC OR Bronco graveyard catalogs for the 73-79 i only see cluster backings,speedometers & circuit board replacements.you might try a salvage yard.or do like i did & install mechanical aftermarket guages which are much more reliable & accurate than the electric dash units.my truck has the idiot lights tho.which i never trust..i understand tho if your after originallity.

 

[FORDification]

It would probably be cheapest to just buy another instrument panel from a junkyard or E-bay to salvage the gauges from. However, if you're willing to pay for new NOS, there's listings for the following for $35-$45 each:

• NOS Oil pressure gauge
• NOS Ammeter
• NOS Temperature gauge

 

[Mil1ion]

To the OP, The fact that you have a 78 is great news for you.

You can pull a cluster out of a 80's E-series van to get the complete cluster.

I have an NOS Gauge if you are interested. it won't be cheap.

I have several experienced ones for less.

Want to piece it together?

You can get the cluster backs at several places but are not necessarily needed.
It is the heat that destroys them.

For the best used one > You want one from a cooler climate.

Gauge clusters (18 pin) are completely different than warning light clusters (14 pin).

ICVR's are 5 volts PULSING output and can be tested at the sending unit wiring or at the back of the cluster

 

[BuzzGun79]

i dont mean to but in but i have a question on my cluster.for one reason or another the cluster plug was cut off the harness. i do have the plug but all leads have been removed.i went & got another at the scrap yard & just cut back a length so i have the color coded wires on the plug.my question is can i either solder the wires back together or use crimp on connectors.im not to worried about the idiot lights,i have aftermarket gauges for the volts,water temp & oil pressure.but i will need the clusters fuel gauge,dash lights,t/s indicators.a new harness is out of the question right now its just to costly & the rest of the wiring is in decent shape,.any suggestions ? thanks Bob

 

[Mil1ion]

You can do anything but it has to be done correctly

For splicing into a harness no less than solder and heat shrink tubing to protect the circuits is the only way.

 

[BuzzGun79]

thanks for the info Mil1ion i thought i could solder them but wasnt definitly sure & i know all wires have to be exactually put back where they belong.that will be the challenging part for some of the wires have discolored over time.i dont know why people have to hack things up of this nature,it really pisses me off...lol.but in time i will figure it out. Bob