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Pc150-3 track tension

JohnnyG1212 · 2018-07-30 15:46

Hey guys. I have a 1988 komatsu pc150-3. One of my tracks is way to loose and I tried to pump grease into it to tighten it up but it keeps seaping out through the fitting. Is this just a bad O ring/Seal or could I have a frozen adjuster on my hands. Below I will attach 2 pictures of it. Any help would be greatly appreciated guys. Thank you for your time

Replies12
  1. #1DIYDAVE2018-07-30 20:13

    From the second pic, looks like you gotta leak coming from that big nut, or under it. I'd get a look at the parts manual, and see what's under the nut...

  2. #2JohnnyG12122018-07-30 20:43

    Thank you for your advice. Yes as I pumped the grease into the zerk it all came out from that big nut. I am hoping all I need to do it replace and O ring but not sure if that’s all that needs to be done

  3. #3heymccall2018-07-30 23:48

    Can the hex under the grease fitting be tightened?

  4. #4JohnnyG12122018-07-31 17:02

    Yes it can. I’m pretty sure I need to replace all of the seals. Just hoping the piston spring and idler wheel arnt stuck

  5. #5heymccall2018-07-31 17:35

    That hex headed fitting, under the grease zerk, is a needle-type valve. When the valve is loose, or the needle within is damaged from overtightening, grease will escape where your picture shows grease coming out. There are no seals to replace in there. Grease the zerk to tension the track, after ensuring that that hex headed valve is tightened. Loosen the hex up to two full turns to loosen the track.

  6. #6heymccall2018-07-31 17:42

    If the grease jack had bad seals, grease would leak out at the other end of the recoil spring. It ain't a seal leaking. The only thing that big nut does is hold the recoil spring in compression. Don't even think about taking that nut off.

  7. #7JohnnyG12122018-07-31 17:43

    When I try to grease the zerk to tension the track the grease comes out where I circled in the picture below

  8. #8JohnnyG12122018-07-31 17:45

    Not really sure what to do. Should I open up the tracks and try to just take link off to tension them?

  9. #9heymccall2018-07-31 17:47

    I understand clearly. Again, tighten the hex head (22mm, I think), then add grease. If it is tight, then, since your track is already loose, remove the two little bolts and bracket (sometimes the bolt heads are tack welded), and unthread/ remove the hex headed fitting, and inspect the needle. That hex headed fitting can hold a ton of more of grease pressure, so, they put a stopper bracket on there to prevent full removal by knowledgeable personnel. Once the track is loosened like in your picture, there will be no pressure behind it.

  10. #10JohnnyG12122018-07-31 21:11

    Ok will try that tomorrow thank you for the help. I will keep you guys posted

  11. #11heymccall2018-07-31 21:56

    To prevent removal by UNKNOWLEDGEABLE personnel.

  12. #12John C.2018-07-31 23:23

    Purchase and install a new adjuster fitting before you do anything else. The get a ring worn into the cone where they seat inside the cylinder. Here is a video showing what you need to know for maintenance on your machine. The video shows Dash 5 machines but it will be the same for the Dash 3.