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Komatsu Dash 5 Hydraulic Tune Up

John C. · 2019-09-01 17:01

I've finally got a video done on the Komatsu Dash 5 hydraulic system pressure adjustments. The video is a bit fast and a little rough but for the most part if you have any experience on excavator hydraulics at all, it will make perfect sense to you. Keep in mind that the Dash 5 and Dash 3 hydraulic systems are the same. The electronics are different. Komatsu Dash 5 Hydraulic Tune Up I already have a video on the Dash 5 electronic diagnostics and the link is below. Let me know what you think and feel free to ask any questions that you have. Komatsu Dash 5 Electronics You can also comment on YouTube and if the programs are helpful please like them both here and there. Good Luck!

Replies15
  1. #1TVA2019-09-01 18:56

    Thanks John! You’ve got a new subscriber and I’ve got a lot of watching to do, because Komatsu is a brand I never worked on and know almost nothing about!!! Just quick question: are they still using computer backed up or assisted OLSS flow controls or gone to totally computer controlled like Hitachi now days?!?!

  2. #2John C.2019-09-01 19:32

    Thanks for subscribing. All the primary controls for the pump outputs I think even today on the CLSS systems are hydraulic. The computer only controls output when the engine RPM drops below a calibrated setting. You calibrate the setting with the hydraulic system. I have some customer machines that are running without computers.

  3. #3TVA2019-09-01 19:39

    Forgive me my ignorance, but in this video you talked about jets, and as remember ( it was very many years ago ) jets are in OLSS system. Does Komatsu abandoned OLSS and switched to CLSS? Just out of curiosity!

  4. #4John C.2019-09-01 19:44

    Only the OLSS system has jet sensors. The CLSS system is closed center load sensing and uses differential pressure between pump outlet and main control valve function outlets to stroke or destroke the pumps.

  5. #5TVA2019-09-01 20:05

    Thanks!

  6. #6davecampbell2019-09-01 21:03

    What would I expect to pay to have the hydraulic tuneup done at a shop that is knowledgeable?

  7. #7John C.2019-09-03 00:32

    The problem is finding a shop that is knowledgeable. I charged less than $400 for the machine in the video. I was on the job site less than three hours total. That included the time it took to set up the video shots and walk the owner's mechanic through what we were doing. The local dealer's minimum is $1,000 just for a field truck to drive to a site. The other issue is the pump was just rebuilt on this machine. I knew the history of the machine and the guys who do the maintenance and who rebuilt the pumps. On an unknown machine, if there is a problem, it could get real expensive real fast. I did the same type of set up on a PC750 in Hawaii that had been messed up real bad. The local dealer there spent three weeks and the owner threw them off the site. It took me three and a half days to get that machine straightened out. It's a big reason I wanted to get something on video. Komatsu is just trash for training people on how their systems work. A good independent that has plenty of hydraulic experience will be able to do a basic check and adjust by studying the book, familiarizing themselves with the pressures and settings, watching the video and doing the job the first time probably in around six hours. Do half a dozen machines and it will take more time to hook up and remove the fittings and gauges than it does to adjust the pressures.

  8. #8funwithfuel2019-09-03 06:10

    Subscribed, thanks.

  9. #9davecampbell2019-09-04 09:58

    Might be cheaper to fly you to oklahoma than have the dealer do it.

  10. #10John C.2019-09-04 11:16

    You could talk to them first and ask them if they know how to adjust the system and then quiz them a bit on what it takes to do it. Ask them if they adjust the jet sensors or the NC pressures or how many gauges it takes to do that. If they know what that means, it might be worth the risk to have them do it. Lugging all the hoses, fittings and gauges through an airport isn't something I'm inclined to do anymore. I've often wondered if FaceTime or Skype would work to guide someone through it. I figured I'd try the video program first.

  11. #11mg23612019-09-04 12:28

    I also subscribed. Great videos John. Thanks!

  12. #12John C.2019-09-04 14:23

    Thanks for the support!

  13. #13TVA2019-09-04 15:21

    John can you recommend any literature to read, to at least have some basic knowledge of Komatsu machines?

  14. #14John C.2019-09-04 17:09

    The only information I've ever gotten was from service manuals.They explain things in engineer speak and then I had to go try to decipher that on machines. I wish I could recommend something.

  15. #15TVA2019-09-04 17:36

    Thanks John!