Page 3 of 3 FirstFirst 1 2 3
Results 21 to 25 of 25

Thread: MEP 804A lots of issues.

  1. #21
    4 Star General Guyfang's Avatar
    Join Date
    Dec 2015
    Location
    Burgkunstadt, Germany
    Posts
    6,259
    Thanks
    12,079
    Thanked 5,578 Times in 2,688 Posts

    Default

    Quote Originally Posted by 155mm View Post
    I would remove and inspect, 2-3 vac
    If you do not do this, adjusting is a waste of time. Clean, un damaged and adjusted properly. The closer to 3 VAC is best, but not over. Take your time. Spin the engine with S10. Better to re adjust 2-3 times, and get it right, then grind the end off. Any damage to the MPU, I would get a new one.

  2. #22
    Private
    Join Date
    Feb 2010
    Location
    Baltimore
    Posts
    11
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    Thank you.
    I removed, cleaned and reset MPU, not too much on it. Starter still stays engaged when running. I pulled the MPU from a good runner, cleaned, installed and adjusted. Still Starter stays engaged when running.

    Is it possible to have a problem in the A5? Either adjustment or a bad unit? One machine has a Tier 2 reset and a Woodward A5. The other is not reset as far as I can tell and has a Berger Colman. Are the A5s interchangable?

  3. #23
    Private
    Join Date
    Feb 2010
    Location
    Baltimore
    Posts
    11
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    Just as a side note, I put the MPU from the malfunctioning machine in the good one and it runs fine.
    Also checked at A5 and getting 2.5ACV on both machines.

  4. #24
    Sergeant
    Join Date
    Jul 2017
    Location
    Wimberley, Texas
    Posts
    73
    Thanks
    51
    Thanked 64 Times in 42 Posts

    Default

    Stay with me here, Im a show me type person, IF ? it were me at this time id want to just for the sake of my own sanity and moving forward know that this starter will actually disengage while in the starting sequence. To do this go in and break the solenoid + wire with a switch that you can open, causing the + voltage signal to no longer try and engage the actual starter .. Its fully expected that indeed this will let the started drop out, simple enuff. presuming it does stop the actual starter your back to where or what is actually still sending a + signal to the solenoid, but somewhere in this we will find your problem have you had the time to check the oil pressure switch, I think it has a switch that as oil pressure build up, it breaks the ckt feeding the solenoid feed, you're fortunate you can contrast of verify your findings between your good working machine and you're non working machine. This will just take some time and an good I'd say ANALOG vom [meter] my preference for ANALOG meters is the instant and visual affirmation of the condition you're trying to check out. where a digital vom is too slow in these circumstances to confirm the actual circumstances/situation. I think I have an 804 TM copy and I will go try and find it and sort thru the starting ckt. You mention you have 2 diff controllers Barber Coleman and a Woodward these both are as good as it gets sans adding a GAC into the mix, but in this contract series you have before you, GAC was not a player. I would not advocate interchanging these 2 controllers, most frequently while not complex, the set-up for the respective engines is a bit drawn out and it would have to be a true last resort before I did consider this type swap.. It will be easy enuff as we dig into this, the signals we will be looking for, will show up, or not.. Ill go try and find my TM's but my bet is Guyfang will see this as he will soon be awake while it is nearing my zzzz time, and be pretty ready to supply the path you need to follow.. best: mac/mc

  5. #25
    Private
    Join Date
    Feb 2010
    Location
    Baltimore
    Posts
    11
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    mcii, the starter does disengage when in run. I started it, disconnected the starter solenoid wire at the starter, then turn S1 to Start and the K2 clicks sending power to the starter solenoid (which is disconnected so I don't grind the flywheel smooth).

    The only thing I can find different between the two machines is voltages on A5 terminals 18, 19, 20.
    Good machine cranking but not started:
    18 24v
    19 24v
    20 0v

    Good machine running:
    18 0v
    19 24v
    20 24v

    Problem Machine Cranking but not started
    18 24v
    19 24v
    20 0v

    Problem Machine Running
    18 24v
    19 24v
    20 0v
    and when turn S1 to start while running I get negative 37v on terminal 20. With a digital DVOM.

    As a side note, the auction I got the problem machine from has about 10 of the same year, 2006, same Tier 2 reset in 2011 and all 2 to 4 total hours. Only one of them runs.

Page 3 of 3 FirstFirst 1 2 3

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •