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Wondering why it jumps out of gear.

Discussion in 'Forklifts/Telehandlers' started by kshansen, Sep 30, 2014.

  1. trackdoc

    trackdoc Well-Known Member

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    Hi there, we run around 140 of those trucks.
    We have never had this happen.
    Can you forward the serial number of the engine that failed ?
     
  2. kshansen

    kshansen Senior Member

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    Nige,

    Maybe you could send me about a dozen of those with some JB Weld to fix my trans.:D

    As this is a very low priority machine all that is going to be done is some repair work to the shift rails to try to make it less of a guess as to what gear it is in. The detent balls had grooves worn in the rails and the interlock that prevents it going into two gears at once was totaly not functional. I would like to be able to do a good job either swap in a used trans or new parts if they were available but that's not my call. It's a shame because with a hand full of parts and a bit of labor this unit could out live me!
     
  3. kshansen

    kshansen Senior Member

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    140 789 Cat Trucks? I can't begin to wrap my head around the support team need for that kind of a fleet:notworthy

    You must move more material before lunch on Monday than we do in a years time!
     
  4. trackdoc

    trackdoc Well-Known Member

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    That's only the 789's.
    We have 785's too.
    You would be amazed how few of us keep them alive.
     
  5. mitch504

    mitch504 Senior Member

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    Nige, do those air start 789s use an air starter motor, or do they start like an EMD, by blowing air into the cylinders? Wonder how well that'd work on a 4 stroke?
     
  6. kshansen

    kshansen Senior Member

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    Do tell! Maybe I'm just lazy but keeping 2 769's on 773 a 988H, 3 980's 3 skidsteers, 1 Back hoe, about 10 pick-up, 2 Miller welders 1 Antique Yale fork lift going along with keeping records on work done, oil samples and the odd crusher pump or stationary air compressor running, repairs to water recycler for washbay functioning, cleaning shop and chasing parts for the above while working 40 hour weeks 10 ten months a year leaves little time at work to read these forums!
     
  7. Nige

    Nige Senior Member

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    trackdoc, the one that failed was S/N 7TR02736. The gear is a 153-1243 - been in use since 1998. It's been replaced by 420-2042 since mid-2012. A new gear is about $300, so we're now replacing all of them (every engine we have bar one has the former Part Number gear) as a one time only deal with the new gear when we pull them for overhaul. Previously that gear was only replaced based on condition when the engine was overhauled at 20k hours. The main problem we have is a number of engines that have already had 1st overhaul - what do we do with the gears in them..?

    Don't get too wound up, the failure mode is sporadic (allegedly) but since we've had the failure it's focused our efforts wonderfully.

    Mitch, they are actually an air turbine starter motor bolted into the flywheel housing. One TDI Turbostart will replace 2 x 50MT electric starters and is about 1/10th of the weight. Why anyone would want to use electric start (including the 6 8D batteries it needs - the air start version of the truck uses 2 x 4D simply to light up the dash panel) on an engine this big I have no idea. http://tdi-airstarter.com/t50.php

    KSH, We have a very small fleet where I am now. The biggest fleet I worked with was 140 trucks, a mixture of Cat 797 & Kom930E, the fleet moved 1.2 million tonnes of dirt a day. We always used to joke that was despite the management not because of it....................
     
  8. kshansen

    kshansen Senior Member

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    After wrestling 50MT's too many times I would love to have one of those T30 starters on our Cat 769C&D. Would be a problem on our 980's and 988H, no air! Every-time I mention our WA600 with the K19 that has the original 1996 50 MT that was installed at the factory and as of yesterday, with just short of 25,000 hours, is still starting the engine like the day it was bought I think I'm going to go in in the morning to find smoke coming out of it:eek:
     
  9. mitch504

    mitch504 Senior Member

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    They use 2 50MTs, when they need more power? I would think you would have trouble with one lagging just enough to accelerate wear on the drive gears.

    The only big stuff I work on is EMD 16v645s. To start them, you start a 6-71 that turns an air compressor, then blow air into the cylinders to direct-start them.
     
  10. kshansen

    kshansen Senior Member

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    I need to confirm on our 773G Truck, but as I recall it has the "Cold Weather" option and it has two 50mt's if I recall. I know when we still had a D399 V-16 genset it had two 32 Volt 50MT starters or were they 36 volt? Been many years since I worked on that one!!
     
  11. lantraxco

    lantraxco Senior Member

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    When I worked the tugboats they were all air starters, Detroits, CAT D399's and 3500 series.... always had one auxiliary generator engine started on battery which we kept in top form. If you lost air, you had to have that one to power the compressors.
     
  12. mitch504

    mitch504 Senior Member

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    That's what these EMDs are in, tugboats. They're just big Detroits. The captain who owns them, (83 y/o) will correct you in a heartbeat if you call his 71s and 53s Detroits, they are old enough to be General Motors Diesels.
     
    Last edited: Oct 4, 2014
  13. lantraxco

    lantraxco Senior Member

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    Mitch,

    Kinda what I figured, something marine with the high voltage systems.... locomotives are usually started off the DC generator I believe, they start them with a gas drive welder in the field?
     
  14. mitch504

    mitch504 Senior Member

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    These tugs are mechanical drive, not electric. I think you are right about the locomotives, but I'm not sure.
     
  15. Nige

    Nige Senior Member

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    In the power station world we used to call them "black starts" - because before you cranked that one engine up, everything was black ..........:D
     
  16. lantraxco

    lantraxco Senior Member

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    Nige,

    Exactly!

    Had that happen on a boat once, luckily in calm seas and open water. The auxiliary was a 6-71, burned a valve for some reason. When the air compressor started the gennie stumbled and went to it's knees and as I was trying to get to the backup the lights went out. Engine room on a tug is not a good place to be with the boat moving and everything hot and the battery lights of course failing to work. Pocket penlight to the rescue again. Of course the Cajun Captain screaming "I got no steering!!!!" every ten seconds didn't help belay the panic I was in, LOL
     
  17. Scrub Puller

    Scrub Puller Senior Member

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    Yair . . . mitch504. I posted pictures of English Mirlees powerhouse engines some time back . . . four strokes, air start with #1 cylinder on TDC.

    The old style English diesels start very easy. Some of the early pearling luggers had 50hp 4LW Gardiners for the simple reason they could be hand cranked and there was no need for batteries or electrics on the boat.

    Even the "big" 24 litre 230hp 8L3B was supplied with hand start tackle and could be decompressed and started on one cylinder . . . possible with one bloke, easier with two.

    Cheers