Results 1 to 10 of 10

Thread: ATC 90, no forward movement

  1. #1
    Join Date
    Nov 2009
    Location
    just below the bridge, Michigan
    --
    1,147

    ATC 90, no forward movement

    I was helping a friend get his 90 going, it had sat in a barn forever. I cleaned the carb and got it running good. But when you put it into gear it goes no where. Not even any wheel spin if you jack it up so the wheels are off the ground. No noise coming from the tranny either. Could the clutches just be shot from sitting so long? If its the bottom end and needs the cases split I am just going to re-ring a different engine in the barn. Don't want to waste my time on this one if its the tranny but the clutches would be a nice quick job.

  2. #2
    Join Date
    Nov 2009
    Location
    just below the bridge, Michigan
    --
    1,147
    Bump....just a little more info, the tranny appears to go though all the gears according to the little indicator on the side of the engine. Anyone ever seen a tranny that did nothing like this? I've seen gears go out or clutches slip but this does nothing at all. No noise either. Took apart and inspected the high low selector and it is good.

  3. #3
    Join Date
    Jul 2005
    Location
    az
    --
    2,001
    the chain didnt slip off did it? or maybe the front sproket is bad? jim
    81 185s
    82 185s with 85 200s motor
    82 185s
    and a 72 ct70

  4. #4
    Join Date
    Nov 2009
    Location
    just below the bridge, Michigan
    --
    1,147
    No, that would be nice though. Its either the clutch, or its in the lower end. I've just never seen a clutch go out that wouldn't even move the wheels. There is a box of ATC and Trail 90 parts in there and a couple other engines.

    Has anyone had a one way clutch completely go out from sitting?

  5. #5
    Pafrig's Avatar
    Pafrig is offline At The Back Of The Pack Arm chair racerAt the back of the pack
    Join Date
    Sep 2009
    Location
    ALASKA
    --
    278
    thats definatly weird that the wheels dont spin... i would take all the stuff out of the hi lo box, then run it. oil will piss out that middle shaft, so watch out. see if the shaft spins, i mean, it should atleast spin in neutral. if it dosent spin, take the right case cover off (after draining the oil). then you can can see the clutch and all, assuming the clutch is even there right next to the clutch is a big gear that is driven by the clutch. this gear is hooked directly to the transmission, so if it turns, and you're supposedly in gear, something in the fina drive WILL turn if your tranny is operating properly. if its not that, and theres no obious problem with the clutch, the clutch adjustment could be out of wack. heres a quick crash course on how a 90 shifts, when you push the lever down, it pulls a pawl, that catches a wheel that turns a drum that moves gears in and out of posistion. however, before it moves any gears, the clutch is automaticly disengaged when you turn the shifter shaft. if you take it apart, you should be able to understand the inner workings of how it disengages. anyways, ultimatly, theres a screw and nut on the right case half in the protusion where the clutch rides. unlock the nut, then back the screw out a long ways. next, put it in gear and start it. if you cant get ANY movement in the final drive, you have to be missing peices. hell, the only three that could be missing are the clutch, the little gear on the clutch, (im not sure if that even comes off) or the big gear thats drivven by the clutch. basicly, if all your ducks are present, one of them must be retarted. we just dont know which one.

  6. #6
    Join Date
    Dec 2004
    Location
    Baltimore, MD
    --
    6,088
    Are you sure that the hi/lo gear selector switch is actually in hi or lo and not in between gears, meaning disengaged?
    Nicholson 500x (Project)
    Nicholson 185s
    Nicholson 110 (That takes an atc70 tank)
    Ascott 500 head/350x (Project)
    Homebuilt Racer Chromoly Suspension 110 (Ragin Runt)
    PK Racing Suspension 70
    A+ Inc Suspension 70
    AWS Aluminum 90 frame
    Hi Performance ATC Suspension frame rd350
    Hi Performance ATC Suspension frame 90

  7. #7
    Join Date
    Nov 2009
    Location
    just below the bridge, Michigan
    --
    1,147
    Yeah. I tried it in hi/low,took it apart to make sure it was good. Found one of the teeth on the hi low gears were busted, swapped them out with another set. Adjusted the clutch (so I thought). I did all the basic stuff.

    I think Pafrig ht the nail on the head, something is missing. Thinking about it when I went to adjust the clutch it felt like it didn't contact anything. And the clutch cover was missing a few screws. I'll find out later today.

    I didn't want to pull the side covers the other day since it was a sand storm it was so windy. And unfortunately my garage is 10 miles away.

  8. #8
    Join Date
    Nov 2009
    Location
    just below the bridge, Michigan
    --
    1,147
    Ha, so that explains it. I pulled the clutch cover off and everything is missing. So that why it was acting like the clutch was totally gone, because it was.

  9. #9
    Pafrig's Avatar
    Pafrig is offline At The Back Of The Pack Arm chair racerAt the back of the pack
    Join Date
    Sep 2009
    Location
    ALASKA
    --
    278
    well how about that.

  10. #10
    Join Date
    Nov 2009
    Location
    just below the bridge, Michigan
    --
    1,147
    Sometimes it helps to have someone point out the obvious. I was racking my brain thinking it was something really complicated, because I had never seen anything act like the clutch was totally gone, and have it go through all the gears perfectly, yet do nothing. Funny thing is someone must have pulled that clutch and gear set out years ago, the dust was solid all the way around. The motor looked all sealed up and complete, minus 2 screw on the clutch cover side. I gotta build a garage on my property, cracking open engines outside makes me un-easy.

//ArrowChat Integreation Code //