Ruston Hornsby 2YBA / Swan 3-Phase Generator

Discussion in 'Help Wanted' started by Rangie, Nov 1, 2021.

  1. Rangie

    Rangie New Member

    Hello Folks,

    I have a Ruston Hornsby 2YBA powered "Swan" generator. I know the engines well enough but haven't come across this small a 3 phase generator before.

    Its a "Swan" by "Engine Applications Ltd" gen set, type RA6000 of 9.4kVA and 415/240v output.

    The generator head is a Stamford / Arthur Lyon type when they were part of the Newage Group.
    Type AB13 (I think, it may be AY13, the data plate is a little corroded), 9.4kVA, 1500rpm 415/240v etc.
    It's currently gently drying out before I attempt to megger/do any electrical work on it.

    "Engine Applications Ltd" dates it between '59 and '73, but beyond that I'm not sure.

    Can anyone date Rustons? Engine No. 486170

    Does anyone have a copy of the diagrams/service manual for the small Stamford/Lyon generator?

    Any assistance gratefully appreciated,
  2. Rangie

    Rangie New Member

    After a couple of months air-drying it was decided to see if the Ruston was alive or dead.

    The Generator outputs were Meggered and found that there was “some” insulation there, to the tune of about 10-20k. It was taken inside, access panels opened-up and a bulb left in it overnight for warmth. It came up to about 1M so it was decided to get it running to see.

    Engine Side:
    • Fuel Pump housing removed and control linkages unseized.
    • Decompressors unseized.
    • Fuel system stripped and cleaned.
    • Fuel tank borrowed from spare 1YBA.
    • Air filter housing borrowed from spare 1YBA.
    • One injector pipe borrowed from a spare YBA.
    • New rocker oil-feed lines made up.
    • Exhaust flange re-tapped.
    • Pepperpot exhaust fitted temporarily.
    • Lucas diesel filter housing installed as the original type's plastic bowl had UV'd and split.
    Electrical Side:
    • Slip rings cleaned & polished.
    • Stuck brushes freed off and cleaned/lapped.
    • Traced the circuit as far as possible to check for nasties.
    • Repaired age/stress-cracked/fractured band on field regulator resistor.
    • Diagnosed/replaced knackered selenium rectifiers with silicon diodes.
    • Fitted a fresh 3-Phase output socket.
    Engine started and ran well, no smoke, suspect the 319 hours on the meter are correct.

    Generator wasn't exciting, 8v AC everywhere. The field winding tails were lifted, it was then excited externally and produced electric OK.

    A strong smell of Garlic meant the Selenium rectifiers were on their way out. When tested they were only marginally operational and one rectifier was passing in both directions! They were replaced with 10A Silicon Diodes and the generator excited immediately. The voltage trimmer resistor needed increasing a fair bit due to the increased feedback voltage (much less volt drop across the Silicon rectifiers than the Selenium ones).

    A small increase in voltage on-load but nothing worrying, just a feature of the old transformer-controlled system.

    Future Work:
    • Re-instate the silent exhaust system.
    • Second Injector Pipe (No.1 cyl weeping at injector), or a pair of new pipes made up with fresh nuts.
    • Blast/paint skid, control box frame and repair control box.
    • Strip/rebuild fuel cut off solenoid.
    • Rebuild/check Ammeter and Voltmeter.
    • Reinstate emergency shut-down system.
    • Strip/clean main terminal strip in control box.

    I'm still looking for a copy of the manual for the Arthur Lyon Co. / Newage / Stamford Type AB or AB13 Alternator / Generator.

    There are a couple of windings I am unsure of which are buried/soldered into the transformer circuits. Possibly to do with load response / partial loss of excitation due to heavy starting.

    Any assistance gratefully appreciated,
    petternut likes this.

Share This Page