Announcement

Collapse
No announcement yet.

Need Transmission expert G260/M20, clunking and can`t hold gear...

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Need Transmission expert G260/M20, clunking and can`t hold gear...

    Problem: Car has loud intermittent clunk shifting into 2nd, can`t hold gear under power in 4th (like clutch slipping, not engaging). If you attempt to park the car on an incline and hold it by just putting it in gear it will hold in 1st but will roll back in 3rd (all while making a sound of what I imagine the clutch being grated sounds like)

    Knowns: Clutch and pressure plate are brand new, flywheel is freshly resurfaced. Output shaft bearing is brand new.

    Potential cause/Issue: When trans was first installed on the engine it was installed incorrectly (forced) and the input shaft on the trans went in to the output shaft bearing on the engine side at an angle and mangled the bearing.

    Theory: The incorrect install screwed the trans and pushed the input shaft in causing the current problems. Thinking I need a whole new trans/rebuild now to correct this?

    If you have read the above, this is where I am looking for any input before I just push the car into a lake....If you want every detail, continue below

    Here is the full detail/story:
    Bought an engine/trans out of a car that hit a barrier. Installed and ran that engine but quickly encountered that the trans was pissing transmission oil (seems to be at the transmission input shaft seal) and the car quickly began to have the clutch slip (my guess is from literally spraying the clutch and saturating it with said trans oil) when trying to engage 4th gear in anger (shifting from redline in 3rd). Like I had to steam clean the underside of the car and every surface within a 5ft radius of the trans. I will say that this combo "whined" in a way that no E30 I have experienced; the transmission oil was full and fresh when I installed it to be clear.

    Pulled the lump and transmission out and went to put my known good transmission on the motor. Had a buddy helping at the time and made the mistake of allowing him to mate the two together while I was handling other tasks. As mentioned above, he he-manned the trans on and in the process had the input shaft misaligned which caused it to not line up with the output shaft bearing. Pulled the two back apart and saw the mangled bearing, so replaced the bearing and the clutch. I took over the install and the trans slid into place with no effort, exactly how you would expect with perfect alignment. Except now I have the problems noted above, despite knowing that prior to that first failed attempt at install that this transmission was perfect. I have bled and replaced the slave cylinder as well as tried shimming the slave, but no change in behavior. Also have used the previous slave cylinder that worked flawlessly on this transmission so I know its not a function of that being different/wrong plunger length

    I am at a loss though and am thinking the trans is toast and my only recourse is full replacement.

    #2
    did you check flywheel thickness after it was resurfaced?

    I assume the output shaft bearing you are speaking of is the pilot bearing
    '84 318i M10B18 147- Safari Beige
    NA: 93whp/90ftlbs, MS2E w/ LC, 2-Step
    Turbo: 221whp/214ftlbs, MS3x flex @ 17psi

    Comment


      #3
      Flywheel was checked for thickness sometime back and I don’t recall any issues. Also, I did run this flywheel on a different engine and same Sachs stock clutch/pressure plate without any issues.

      And yes, pilot bearing is what I meant. Sorry for any confusion there

      Comment


        #4
        Grasping at straws here, sounds like clutch, but you seem confident about that. Is the shifter linkage installed correctly? It's not impossible to install the rod backwards which may cause only partial engagement of the gears????? If you drain the transmission fluid is there any debris in the fluid?
        2004 525i Manual - 1985 325E Coupe Manual

        Comment


          #5
          I know, it seems like clutch to me as well, but I can’t make heads or tails of this. Clutch is brand new and I have actually tried two clutches now with the same result. One of the clutches was used but was in thickness spec.

          I have horrible luck with these cars and am just about to give up on them

          Comment

          Working...
          X