1979 Ford F150 4X4 dash cluster problem

Discussion in '4x4 trucks / off road' started by ErwinRommel, Aug 1, 2009.

  1. ErwinRommel

    ErwinRommel Banned

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    Well, my gauges seem like their not working like they should.

    -My speedometer doesn't work.
    -My alternator gauge works I guess because it moves and stuff.
    -My oil pressure gauge works I reckon. It stays in the normal area but more toward the Low way but over the OR in Normal
    -My gas needle moves very very slowly but only moves up to the E and no farther.
    -My temp gauge works a little and moves up over time once the engine warms up but it take it a bit due to the engine is cool at first.

    I need my speedometer working and my gas needle.

    I wonder if the speedometer sensor is messed up.

    I don't know what could be the gas needle problem...

    What could be the problem?
     
  2. 75K30

    75K30 Senior Member

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    Your speedo works off a gear and not a sensor. The cable goes to the transfer case and is held in with one 3/8" bolt. Remove this bolt and retainer and pull the cable out to inspect the gear. If the gear is bad then you must replace it. Chose the one with the same color as these are specific to vehicles. Different colors are available to compensate for different gear ratios or tire diameters.
    If the gear looks fine then you must inspect the cable itself. If the cable has broken within the housing then you will have to replace the entire cable. Pulling on the speedo cable itself (the inner portion) can help determine whether or not its busted.
    You must also make sure that the cable is plugged into the dash cluster itself. Be careful if you handle these old clusters. The white part is fragile and may break easily. Do some verificatoions of this before we discuss the replacement of the cluster. If you have to replace it, you will be looking for one out of an 80's van. More on that later should we find the need.

    OK, the other gauges. Your gas gauge recieves small voltage through the sending unit, and you have to make sure that the wires are clean and not shorted anywhere.
    You issue can be a couple of things, either a bad sending unit, or even a bad circuit board in the dash cluster. Since all of the gauges appear to have a problem then I may lean towards the fact that the printed curcuits in the cluster are going bad.
     
  3. ErwinRommel

    ErwinRommel Banned

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    What gear?
    I know my tranny seems to not change like it should sometimes. I think. I think it may be slipping. But after it warms up....it changes good.
    So I have to buy a new cluster eh?
     
  4. ErwinRommel

    ErwinRommel Banned

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    Well my temperature needle wire that goes to the water pump or whatever is messed up.

    I just might not buy a cluster and just buy regular manual guages. Just keep the speedo though on the dash.


    What do you think?
     
  5. ErwinRommel

    ErwinRommel Banned

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    Well finally pulled the cluster apart and the speedo cable is hooked up to the speedometer and I checked the gears in the transfer case for the speedo and it looked fine.


    My guess is, is that the speedo part doesn't work no more.


    I had to use an angle grinder to try to get the cluster off though because of a stupid rusted screw wouldn't come out!


    HOW DO YOU TAKE THE CABLE AND STUFF OFF THE CLUSTER?!!!?!

    My cluser is just hanging by wires now. Lol.
     
  6. ErwinRommel

    ErwinRommel Banned

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    Well I decided to buy me some manual gauges from Advance. Got the Temp, Oil and Volt meter.

    My plans are to take out the original dash cover piece and make a custom dash cluster.
    I want to put diamond plate across it and then install all my gauges. I think it would look bad ***. I think 75 has one in his yeller truck like that.
     
  7. rickahyatt

    rickahyatt New Member

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    I, too, have that problem on my 81 F250 Ford Gas guage works but nothing else (To include reverse lights) Someone's rewired the **** out of it. But, mainly, I'd like to get the temp guage & speedo working. Have tried checking plastic gear, it's OK. New cable that will run the speedo with a drill attached. Can it possibly be wrong gear from dealer? If I put my finger in trans can turn metal gear. I also have a spark plug that apparently has a worn valve guide & always has to be replaced. Told to put in plug with wider gap, or just run hotter plugs. Good idea? (I never know how hot the engine is.)
     
  8. rickahyatt

    rickahyatt New Member

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    Oh, fixing truck because my Mazda 626 blew a head (Gasket?)
    Do you have any faith in that new expensive sealant I've seen at the auto parts stores? Have to drain all coolant, etc.., put in & it gets hard as rock?
     
  9. jgreen77

    jgreen77 New Member

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    75K30,
    I have a 79 F250 and I need to replace the printed circuits on the back of the cluster as the dash lights won't work. I intend to leave this truck to someone who will appreciate it in my will. What is the best way to replace the circuits? I would like to replace the entire cluster due to the clear plastic is cracked, can I replace the entire cluster and keep the same speedo and odometer? Your help would be appreciated.
     
  10. chevychase

    chevychase Senior Moderator Staff Member

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    Gosh been so long since i messed with type cluster. Pretty sure you can change all keep your instruments.
    Seems all put together with screws... take circuit board off.
     

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