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Volvo A25C Tacho

Discussion in 'Other Earthmoving Equipment' started by Hoganter, Aug 20, 2021.

  1. Hoganter

    Hoganter Member

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    Hi
    I have a A25C water cart in NSW.
    Serial 5350V12593. The original tacho was not working and I thought I detected a signal, so bought another from volvo penta for $900 as CJD are not supplying parts for these like temp gauges and brake boosters so far. Anyway new one plugged straight in and no joy, however the rpm read out on the overhead ecu screen works, so I figure I am getting a signal from the engine. Am going through wiring diagram in manual but if anyone knows anything it would be appreciated. thanks terry
     
  2. sfrs4

    sfrs4 Senior Member

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    Firstly so there is no confusion, do you mean revcounter or speedo?
    I am assuming you mean the rev counter top right of your center instrument panel, this is controlled by a relay in the left hand distribution box, the left of the two big relays at the top of the box. no longer sold by Volvo as far as I know and neither do any of the aftermarket people I deal with. good luck with your hunt for one.
     
    Last edited: Aug 20, 2021
  3. gggraham

    gggraham Senior Member

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  4. gggraham

    gggraham Senior Member

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    Sorry wiring is in 3 pieces but old prosis doesn't allow the same functions as newer versions. Hope this helps
    a25c wiring 3.jpg
     
  5. gggraham

    gggraham Senior Member

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  6. Hoganter

    Hoganter Member

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    Yes

    Yes Rev counter, the speedometer works. thanks for this
     
  7. Hoganter

    Hoganter Member

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    Thanks Graham much appreciated. feeling much more confident now. I feed on hope. Cheers
     
  8. Hoganter

    Hoganter Member

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    These machines are hard to source parts for if the dealer stops supplying, but there are work arounds. I put a new brake booster from an A25D on the A25C. I just had to keep guessing serial numbers in the D series until the computer said yes.
     
  9. gggraham

    gggraham Senior Member

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    As an after market parts supply company in Canada we deal with Blumac, American Crane & Tractor and National Tractor Parts. They have the SLP after market parts for Volvo if you need parts for your Volvo might be worth looking into. Like I said we are a dealer so we deal direct not sure how a consumer would deal with these companies, possibly through a local dealer.
     
  10. sfrs4

    sfrs4 Senior Member

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    The Master Cylinder and Air Chamber are still readily available in the aftermarket for the C series, I have 2 on the shelf, most things are easy enough to get hold of for the C series, with the exception of a few specialist parts like the speed rotation relay. Main Dealers have stopped stocking parts for C's as they don't have the demand, but us alternative suppliers have a wealth of companies still supplying parts.
     
  11. Hoganter

    Hoganter Member

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    It works
    I spent two hours getting out what I thought was the engine speed sensor as its output wasnt changing when revs changed, but it was a transmission temperature sensor.
    Then found engine speed sensor on timing gear.
    Then found it hard to read output, but got 8v AC on multi.
    Then it went to a overspeed relay which turns a light on dash if it over revs.
    Had trouble reading output to tacho so thought it was the relay.
    Then retrieved the old tacho from the car where it did 600 miles on the floor, plugged in and worked.
    Machine had been sitting for years so maybe it was just stuck.
    Removed new tacho and saw it was 12V so probably cooked $900

    Remaining issue is that the machine articulates or turns right when parked after starting it.
    The steering wheel turns by itself.
    Seems to be ok when warmed up.
    Any clues appreciated.

    thanks terry