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Old_John_T's avatar
Old_John_T
Explorer II
Sep 16, 2013

Onan 6.0 CCBK Cranks over too slow

My buddy has an Onan 6.0 CCBK 3R-1600 D LP Gas Generator SN 0772474342 out of an old Travco Motorhome and I heard it start and run like a year ago. He just re installed it at his home for a backup and has two new 12 volt batteries wired in paralell for the cranking system all new good cables etc BUT WHEN HE TRIES TO START IT SHE CRANKS OVER SO SLOWWWWWWW AND TOO SLOW TO START. Its one of those generator self start types NOT an independant DC starting motor unit. I cant find a manual for the 6.0 CCBK LP gas and does anyone know where to get one and/or why it cranks over so slow despite two new 12 volt paralell batteries and new cables n connections etc.

Old John T in Indiana
  • Old_John_T's avatar
    Old_John_T
    Explorer II
    Sep 17, 2013
    THANKS KELLEY the parts and wiring manuals show me the parts I suspected to be condensors are indeed that and it gives me the sizes. Im having the owner clean and polish the rings and commutator etc as I think all the 40 yrs of dirt and oil and gunk on the rings and commutator has to contribute to slow cranking


    John
  • dougrainer's avatar
    dougrainer
    Nomad
    Sep 17, 2013
    1. REMOVE THE 2 SPARK PLUGS AND SEE IF IT CRANKS FASTER
    2. THE OLD STATOR/ARMATURE TYPES, IF THERE WAS A SHORTED WINDING, THEN IT WOULD CRANK SLOW. Doug
  • Old_John_T's avatar
    Old_John_T
    Explorer II
    Sep 17, 2013
    UPDATE I pulled the big brush cover off and theres 40 years of dust n dirt n crud and the slip rings nor the commutator are clean n brigth n shiny plus a wire was broke off one of the slip ring brushes that leads to something that resembles a big condensor??? No idea what it is. Next is a good clean up n check brush hold downs and their length etc n see where that wire was supposed to go??? The batterys and cables and grounds are all new n clean n bright so I suspect the brushes for now

    John T
  • Kpackpackkelley's avatar
    Kpackpackkelley
    Explorer II
    Sep 17, 2013
    TEXAS wrote:
    Check the DC brushes. If they are not making good contact with the rings. It will be hard to start. If you remove the band on the gensection. The DC brushes are the ones towards the engine. Kpack has it right sorta. Takes a big fooken battery to crank it.

    Texas you should have put SORTA in Capitol letters . I'm trying till you get here.
  • TEXAS's avatar
    TEXAS
    Explorer
    Sep 17, 2013
    Check the DC brushes. If they are not making good contact with the rings. It will be hard to start. If you remove the band on the gensection. The DC brushes are the ones towards the engine. Kpack has it right sorta. Takes a big fooken battery to crank it.
  • Old_John_T's avatar
    Old_John_T
    Explorer II
    Sep 16, 2013
    Thanks, I got the manuals and they match his genset. When I saw this start n run the last time it was in his RV Bus conversion which had six deep cycle golf cart batetries in series paralell for 12 volts and A TON OF CCA AND AMP HRS more then he has now. Im going to check his ground connection tomorrow.

    John T in Indiana
  • Kpackpackkelley's avatar
    Kpackpackkelley
    Explorer II
    Sep 16, 2013
    Alright I've sent the first manual CCKB service Manual 927-0503 . See if this matches to your unit ? I'll look for some more .
    If this unit is exciter cranked you need a very large battery with good connections and cables and free brushes in the holder.
    Come over to this website if you can't get it going and give your model and serial number these guys love those old onans. http://www.smokstak.com/
    One of the guys one this site went to look at a old exciter cranked gen . He asked the old German man what he new about the gen. He answered your going to need a big flagging battery .
  • Kpackpackkelley's avatar
    Kpackpackkelley
    Explorer II
    Sep 16, 2013
    Pm me your email and I'll send you the manuals. Make sure your brushes are free to move in there holders. It will keep it from turning.

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