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621d lack of power i’m told

King of Obsolete ยท 2014-04-21 10:50

we went on a 100km round trip over the closed winter road to deliver freight and bring a sick case 621d loader to the Kingdom. first problem is the hanger bearing broke and ate the drive shaft but since it is a holiday monday and everything is closed i can't order parts until tuesday. in the mean time i'll whip up something so i can test the engine for power. any ideas on where to look for loss of power. thansk KoO Published Author

Replies12
  1. #1old-iron-habit2014-04-21 23:03

    In your weather I would suspect fuel filters first, especially if you have had any thaw days lately. Seems any frozen moisture in the fuel tank moves to the filters on the first thaw. Easy to check anyway. Good luck.

  2. #2Hardline2014-04-21 23:44

    Filters, lines or any fittings that have a 90degree fitting like coming out of the tank debris like to collect In The fittings.

  3. #3Nige2014-04-22 11:19

    Anywhere in the fuel lines where there may be a "hidden" screen, often found in (but not limited to) fuel injection pump inlets. From outside it just looks like a pipe fitting, open it up and it's a whole different story.

  4. #4d4c24a2014-04-22 15:48

    i had problems with a 13 ton case some years ago ,had a gauze on the inlet side to the lift pump , had to remove the banjo fitting to see it

  5. #5King of Obsolete2014-04-24 00:32

    thansk for all the info guys. i priced out the drive shaft parts and it only came to $5400.00 but the a little bidie told me that the clutch packs for second gear are toast. to fix second gear it is a $30,000.00 repair and there is no sense in tossing $5400.00 at the drive shaft if it would be able to turn. tonight i did some quick repairs to all the broken drive shafts so we can take the machine out and do a little testing to see if second gear is toast. i picked up a $59.00 hanger bearing instead of the $289.00 one from case. then i welded up the broken yoke and sleeved the thin spot on the rubbed part of the drive shaft. lots of welding and black paint sure did make things look good. in the morning i'll install the drive shafts and let my co-star gerry go push some snow. any ideas on checking the second gear to make sure it is really toast and not out of adjustment or a switch??? thansk KoO Published Author

  6. #6King of Obsolete2014-04-30 22:28

    with the broken drive shaft welded up so i could do some testing of the machine. these dumb lights on the dash stayed on. what are they and what are the gauges mean too. i know what battery and fuel is but have no idea what the others are. today i ordered the new driveshafts and while i wait for them to arrive i started air arcing out the cracks in the bucket. it was a nice day outside for doing this work. thansk KoO Published Author

  7. #7Nige2014-04-30 22:51

    The light on the left appears to be low coolant level. Possibly that light also puts the "stop" light on. Have you checked the radiator..?

  8. #8King of Obsolete2014-04-30 23:04

    thansk nige -- that would explain why there is no electrical going to the top of the rad and someone has joined the wires. first thing we did was top all fluids before we started working on the machine because we know nothing of this machine or what has been done to it. thansk KoO Published Author

  9. #9Cmark2014-05-01 01:03

    If you suspect second is slipping, a stall test would confirm. Check the stall RPM in a gear that you think is good. Then if the RPM is any higher in second, you've got slippage. Don't go too hard on it though. You could turn a worn clutch into a crispy carbon mess very quickly.

  10. #10King of Obsolete2014-05-01 10:21

    cmark -- thansk for the info. we think with the trans cooler almost plugged it might have got the trans a little hot causeing slippage. the funny thing is on this machine it is all grapevine info that we are getting on the machine, no first hand info. it is like trying to solve a mystery. is there any place to put a pressure guage on the trans to see what is going on??? thansk KoO Publsihed Author

  11. #11Nige2014-05-01 12:48

    Not being familiar with this model there might be a simple visual check you can do. Is there a drive shaft connecting the engine and the transmission..? If the answer is yes then with the service brake pedal (not the neutralizer) depressed go from neutral to any gear. In neutral the drive shaft will be turning, as soon as you engage gear it ought to stop. If a clutch is slipping the shaft may slow down but not totally stop. Otherwise do as CM has suggested. Put the transmission in each gear successively and accelerate the engine to the maximum RPM. This is a condition referred to as "torque converter stall". If the transmission clutches are good then the RPM attained by the engine will be the same in every gear. If you have a transmission clutch starting to slip the converter stall RPM for the affected gear will be significantly higher than all the others. No pressure gauge required. Regarding your coolant level alarm - judging from the photo I think the coolant level sensor might be bad and someone has attempted to bypass it to solve the problem. Be careful though, it may not be the sensor but a wiring fault.

  12. #12Cmark2014-05-01 16:25

    Sorry KoO. I've got little experience of Case loaders. My comments above were just how I'd go about troubleshooting any torque converter drive machine.