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? for ATCO about “o” rings

firetruck dvr. ยท 2010-11-20 19:31

When did cat go to the "D" style rubber gaskets in their hyd. systems? We have a 99 model D4C LGP and it blew an angle cyl. hose yesterday. I could not tell if the O rings were the "D" style or not. We have a 2007 304cr mini ex and it uses the "D" style (found this out the hard way). I have a "D" ring kit ordered from Cat. Kit cost almost 600.00 by the way!! Anyway I put the D4 back with new "O" style rings and it seems to be working fine? Thanks in advance!

Replies5
  1. #1Lee-online2010-11-20 19:39

    Cat uses both D and O rings. You can tell by looking at the grove it sits in but generally the higher pressures use D rings. drive lines, Pump outputs etc.

  2. #2willie592010-11-20 19:44

    Wow, when did they go with D seal rings? Not sure, but Cat has been using D rings in various applications for years. And it's not easy to distiguish it's a D ring seal if it's a connection that been made up for a long period of time, the seal doesn't look much different from an o-ring, squashed and hard. I can only say the groove the o-ring sets in is a bit deeper when using D ring seals as opposed to typical o-rings, hence the reason an o-ring will fail if used in a D ring milled groove. Edit, well I'll be dog gone...Lee done went and beat me here. Bah ha ha haha

  3. #3koldsteele2010-11-21 10:03

    I might be wrong on this but original they where metal clad now there all rubber ..been around for a long time .

  4. #4Lee-online2010-11-21 10:09

    yes, only see them once in a great while but they are still out there.

  5. #5firetruck dvr.2010-11-23 13:10

    Thanks for the info guys! It is fixed and working fine!