Starter drive won't stay engaged

Discussion in 'Electrical' started by harvey13118, May 8, 2010.

  1. harvey13118

    harvey13118 Member

    56
    0
    0
    05 Heritage, under load the engine will turn over a few times and then starter disengages and grinds on ring gear.

    Can watch drive in the ring gear move to disengage as engine compresses then fully engage off compression. Pull spark plugs, no load, drive will stay fully engaged.

    Replaced the starter clutch. Cleaned and relubed all gears. Cleaned all contacts, new 310CC amp batt. Same problem.

    Have looked for new solenoid. I think a problem with hold in under load.

    It does not look like solenoid is replaceable on this starter.

    Or could the starter shaft be worn enough to cause starter to act this way?
     
  2. Jack Klarich

    Jack Klarich Expert Member

    18,544
    153
    399
    Starter jack shaft going bad?
     
  3. glider

    glider Veteran Member

    25,464
    108
    44
    Starter drive needs replacing.
     
  4. harvey13118

    harvey13118 Member

    56
    0
    0
    Glider it is a new drive installed. I called starter clutch.

    Would the lack of torque or motor speed on the starter motor fail to hold jack shaft and pinion gear into the ring gear.

    Starter work perfect with no load. Test good.

    I think I found the problem. Primary chain a tad loose apparently that little bit would allow the engine comming off compression to disengage the drive.

    Thightened chain to spec starter works fine now.

    GO FIGURE! Something that simple yet overlooked because not that loose.

    Another lesson in the school of hard knocks!

    I appreciate the thoughts what to look for it gave me good direction and some focus into what and why.

    Spoke to soon! The Jack shaft bolt had not been tightened to spec. When tightened the drive drops back out. Loosen the jack shaft bolt it turns over perfect.

    WHY IN THE WORLD would that happen. What would cause this? I am confident I can not run the bolt loose. What would wear?

    Why when tight not work? Why when loose it work? What am I missing?
     
    Last edited by a moderator: May 17, 2010
  5. Dan89FLSTC

    Dan89FLSTC Banned

    97
    0
    1
    Check connections at the solenoid, the small wires that come from the relay. It could also be a bad starter relay.

    On second thought, it sounds like the starter relay is doing it`s job. But something is happening in the solenoid.

    Have you disassembled the solenoid and inspected it yet?
     
    Last edited by a moderator: May 9, 2010
  6. harvey13118

    harvey13118 Member

    56
    0
    0
    I agree Dan I keep turn back to solenoid. Couldn't locate any specs for the springs.

    Starter off for #6 time. Nothing to loose this time have gas can and matches standing by. New spring came with drive so think that probably OK. Start stretching solenoid spring 1/4 inch longer and the short bendix gear spring stretch that.

    It is working now. However have pumped all the oil out of the engine, oil tank unhooked, so will pull plugs, no load, and turn engine over when I refill.

    Any thoughts???
     
  7. NEWHD74FAN

    NEWHD74FAN Experienced Member Retired Moderators

    8,176
    98
    16
    Harvey, can you post a picture of the loose jackshaft and fastener? It does sound rather odd, but the spinning starter drive should throwout the gear, maybe the shaft is bent or mounting not "square", not allowing it to extend all the way, is there a shim/spacer or plate that is not installed correctly in the assembly?
     
  8. Jack Klarich

    Jack Klarich Expert Member

    18,544
    153
    399
    The starter solenoid is an electro magnetic switch, if the starter is engauging but not turning the engine over probably not the solenoid I would further check the jack shaft is not engauging the ring gear correctly or the drive itself is bad and dis en gauging when under load, keep it simple and you should find your answer:D
     
    Last edited: May 9, 2010
  9. harvey13118

    harvey13118 Member

    56
    0
    0
    I checked and rechecked. All parts seem to fit fairly tight the exception is the bendix gear with the primary cover removed.

    I stretched the solenoid spring a good 1/4 inch last time I had apart. It's all together now except oil tank and primary cover I have tried the starter several times in past 4-5 hours working perfect as it should. I put the old batt in temp to draw down voltage and see if will still work and it has.

    I am at a loss why stretching that spring and the bendix spring would solve the problem. I did also clean all hi temp grease out and relube with Lubriplate engine assembly grease/lub.

    I also can not locate any spring kits for starter. It is going together as soon as I get new crimp clamps. Next time it will be a new starter unless I can find COMPLETE rebuild kit with springs.

    Thanks for all the thoughts. If I do take apart again I will take measurements of springs and others to post.
     
  10. NEWHD74FAN

    NEWHD74FAN Experienced Member Retired Moderators

    8,176
    98
    16
    Harvey, understand perfectly, having to cycle thru taking things apart and back together over 1/2 dozen times can be a test of patience (we've all been there!), good thing you did not use the gasoline or matches lying around in the garage...:devil