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Problems w/ Grove 700E

Savage ยท 2011-05-10 12:37

Any ideas on why a crane after about 2 hours of running would loose power. We can let it sit for 20 minutes then were good for about 2 more hours. You could heep running it but it just keep getting worse. If you take the load off the motor it revs fine but as soon as you go to do something it just bogs down to the point if you don't stop it will kill the engine. None of the gauges show anything getting hot, also tried changing fuel filter, still no help. Were pretty sure it's some thing electrical getting hot, but haven't pin pointed it. Just wondering if someone else has had this problem or one similar one and what was the cause. Thank you

Replies18
  1. #1Savage2011-05-12 12:20

    No Ideas?

  2. #2BillG2011-05-12 14:12

    Not being familiar with this model, I would run it until it starts to loose power and then loosen the fuel fill cap. If this doesn't help, also when it starts to loose power loosen the fuel return line and see how much is being sent back to the tank. If neither help, post what engine and other particulars are involved such as hydraulics maybe getting hot.

  3. #3Plan B2011-05-12 15:22

    So it only bogs down and looses power when you operate controls? i dont know if having a hyd. filter clogged would bog down the engine but you might wanna check it anyway.

  4. #4heavylift2011-05-12 18:31

    i ran one, it was a computer control thing,sensor. But the crane wouldn't do anything but idle, The crane functions worked. It would not drive at all , as with everything it needed a computer to fix the computer no throttle response at all for the most part, every once in a while you could get a few more rpm from the throttle. If and when you had more rpm, a function would take it back to an idle. Don't know what the part was, but not a dealer stocked part , it had to be overnighted.

  5. #5Savage2011-05-12 22:43

    That is correct. When the controls are operated or if you try to drive it. Didn't think of hydraulic filter but will check that. I know it has a Cummings engine but not much else gonna have to look in to that. I don't beleive the hydraulics are getting hot because the gauge is still in the green. Now touching the cylinder, they are pretty warm but the gauge is showing 175F. Now it does rev up and runs fine for about 2 hours then it slowly starts loosing power. What I mean is each lift there after it keeps getting easier to bog down. And after about 6 short lift you can acually kill the engine by working the winch or boom. The swing just bogs it and won't kill it. Thing is there is another 700E from another base that they put a used motor in. It does the same thing but all the time. I have a feeling it could be the same problem on both. The other machine took 3 months to get a new long block over here and now they have all the accesories ordered and that could take another 5-6 months. Appreciate the ideas and will try to get more info Thank you

  6. #6MKTEF2011-05-16 11:20

    I have all the manuals as PDF, but they are rather big to mail to you. There is a 5.9l qsb? in those cranes. The interface between the crane and the engine is rather simple, not anything that will reduse power over time.. The communication to the engine goes over a Canbus network. There is both a connection on the carrier and on the upper part. I will suggest that you spend some time checking out your fuel system. After what you have described, i will guess something is wrong with your fuel supply. Either something in the tank obstructing the suction line, or inside the fuel line/filters. One of ours was operating in +60 C in Tchad without any problem at all.(there is som pics in a Tchad thread somewhere here. And of course u got enough water in the engine? Remember to drain air of the cooling system too.

  7. #7MKTEF2011-05-16 13:56

    Regarding hydraulics, you can run it hot, then disconnect the whole hydraulic pump package. There is a handle by the engine cover. Round nob 5 " of movement. After disconnect, see if power is gone. One time i had it disconnect while driving, wondered a lot why i coulden't lift the boom....:cool2 Service manual is 5,07 mb and user handbook is 1,98Mb

  8. #8Savage2011-05-17 07:12

    Thank you for the replies. But I'm not sure on the details of the engine and hydraulics. I'm the operator having to deal with the problems while it is being trouble shooted. Gonna try and look at the service manuel after MKTEF sends it my way

  9. #9MKTEF2011-05-17 07:12

    We are also awaiting some pics of the cranes here.. Without all the special details of the camp...(security stuff)

  10. #10Tiny2011-05-17 20:24

    non vented fuel cap on a non vented tank or tank vent plugged ??? just a thought .

  11. #11Savage2011-05-19 07:27

    This kinda pic?

  12. #12Savage2011-05-19 07:39

    I had to add this one too funny. Wasn't me. Underground box covered by 6'' of rock. But did have to help them out.

  13. #13heavylift2011-05-19 10:24

    I found a water meter vault with a 35 ton crane I took a bit off creative outrigger jacking to get it out.

  14. #14Plan B2011-05-24 20:42

    If your in LA you should call H&E equipment. I used to work for them and you should be able to get a hold of someone there who knows all about that machine.

  15. #15Savage2011-05-25 01:38

    I'm working in Iraq. So that is most of the problems with getting parts. Mostly just takes a very long time 3 months at least.

  16. #16Dmconstruct2011-12-07 18:41

    Any luck with your problem? I'm having the same issue with a rt855

  17. #17Dmconstruct2011-12-17 06:34

    Update. Replaced both fuel filters and it solved the Loss power issue

  18. #18Hard Nocks2011-12-19 11:00

    Good to hear that you solved your issue. Fuel filters seems to be the most common issue with power loss on a diesel motor, and if it isn't the filters, then at least pulling the filters is cheap, and will tell you if you are getting fuel as far as the filters. Thanks for the update!