maladjusted pushrods

Discussion in 'Touring Models' started by iamron6113, Oct 20, 2014.

  1. iamron6113

    iamron6113 Member

    I cut out the pushrods to rebuilt cam case on my TC88- 04 FLHPI: bearings, tensioners, O-rings.
    I bought S&S adjustable pushrods.
    While installing them I thought I was at TDC in front cylinder. So, installed pushrods in front and waited for the lifters to bleed down. Then, rotated engine and did same at rear cylinder.

    BUT, after the fact, I realized I bike was at OTDC for front cylinder, not TDC. When I cranked the bike - it sounded wrong. I cut it off in 3-4 seconds later. When I pulled pushrods they were fine. but, both lifters in rear cyl now, were collapsing too easily. Took them apart, cleaned and reassembled. Dropped them in oil and waited a couple days but they were shot. I bought S&S lifters for a 2d try. After installing lifters I was extremely careful to make sure I was at TDC in front cylinder (rotated rear wheel forward until I was blue in the fact to make sure I was at TDC) before installing pushrods in same sequence as above. I turned rear wheel by hand several times after installation- listening for any funny sounds, rattling, anything. Didn't hear anything unusual, realizing that turning wheel by hand not definitive. Now, I'm scared to crank the bike.
    Does anyone know if there are clues, signs, indications, anything that might indicate damage in rocker area after error on 1st pushrod installation- - without cranking the bike or having to pull the rocker covers?
  2. stray dog

    stray dog Junior Member

    Hi Ron,
    I'm a little confused with the front otdc then rear lifter problem.
    You are adjusting front or back with that piston at TDC on the compression stroke right? You will know this when both lifters are down (ex lifter up @ TDC on exhaust stroke). You want to be on the base circle of the cam when adjusting the PR's.

    It's usually good to replace the lifters also, maybe you had bad lifters. Was the bike making lifter sounds at start up before?
  3. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator


    What I do is leave the spark plugs out and rotate the rear wheel by hand listening to the engine for "bad" noises. If that works, then I turn the engine over with the clutch pulled in and the spark plugs out. Just enough to see oil pressure and listen for noise that indicates a problem (say about a minute or so). If all that is good, then reinstall the plugs and fire it up!! Back it out and ride!!!


  4. iamron6113

    iamron6113 Member

    Thanks TQ,
    that sounds good. I'll give it a try. Ron
  5. stray dog

    stray dog Junior Member

    hope all is good Ron.
    let us know how it turned out
  6. iamron6113

    iamron6113 Member

    As far as I know, there were no lifter noises before I did the cam rebuild. But, honestly, I'm not sure I would be able to distinguish a lifter noise from some other sound coming from the same area.
    The noise I was hearing initially, that prompted opening the cam case was coming from inside the cam case . . and turned out to be a bad needle bearing.

    On the OTDC thing and lifters. I mean that I thought I had the bike in TDC for the front cyl. when installing lifters in the front cyl. But, it turned out I must have been in OTDC on the front. So, after installing pushrods in the front + lifter bleed down, then, when I rotated the rear wheel to do the same in the rear cyl. I presumed I was in TDC there as well. Obviously, that was not the case. I'm not sure why the lifters in the rear cyl began collapsing too easily AFTER the first try. . . I'm hoping that the maladjusted pushrods caused the impact to damage the lifters and not something in the rocker area.

    What I have learned lately which should be of interest to any who are unaware is that even on bikes having timing marks- there are different timing marks to indicate TDC and OTDC. So, without knowing that, even if you have a bike with timing marks, still you can THINK you are in TDC when actually you are in OTDC.
  7. dolt

    dolt Senior Member Contributor

    I have been wrenching on TCs for years and that's a new term for me. TDC, ATDC and BTDC I am familiar with but OTDC is a new one for me pleas explain.

    Adjusting pushrods remains a mystery for the uninitiated DIY guys. There are various ways but the KISS way is to rotate the rear wheel in top gear, plugs removed, until you hear the compression whoosh out of the target cylinder; piston must be on the compression stroke. The piston can be at TDC on the exhaust stroke but the cams in overlap and lifters not completely on the heel/base circle of the cams. Once you hear the compression whoosh ( you can also hold a finger over the plug hole) out of the cylinder INSERT a straw or something similar into the spark plug hole and "bump" the rear wheel until you find TDC. Piston can be a little before or after TDC for pushrod adjustment; adjust pushrods. Rinse and repeat for the next cylinder.

    You may have bent a valve if pushrods were not adjusted properly. You could run a compression test before firing up the motor again to verify that a valve has not been bent. If I knew what OTDC meant, I could better respond. Many a valve has been unknowingly bent from improperly adjusted pushrods.:icon_wink:
    Last edited by a moderator: Oct 21, 2014
  8. Jennmarr

    Jennmarr Junior Member


    Glad you asked the question Dolt. I've been wracking my brains trying to figure out what OTDC was.
  9. Jack Klarich

    Jack Klarich Expert Member

    does OTDC = Atdc?
  10. stray dog

    stray dog Junior Member

    I was thinking OTDC meant OVER or after but I'm not sure either.
    Another thing I have questions on are these timing marks. The only mark I'm aware of is the mark on the cam plate that helps line up (time) gears/sprockets between crankshaft and rear cam centers. I really don't know if that has anything to do with TDC..?? (or if that is what the OP is talking about). Maybe someone could chime in here on this before Ron cranks that motor over.
    I've only did this once but checked TDC like Dolt described in post #7.