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1996 Case 1840 will not boom up.

Geoff Henderson

New Member
Joined
Feb 10, 2019
Messages
1
Location
Virgin Islands
Recently acquired a 1996 case 1840 skid steer. Had a known problem where the boom was not operating properly. This unit has hand-operated controls . When I first received the machine if I manipulated the foot control valve by cycling it on and off constantly for the auxiliary controller the boom would operate somewhat. To be clear if i held the hand control lever in the up position and cycled the auxiliary foot control over and over It would move slowly going up but seemed fine coming down (down without using the foot auxiliary valve). I have taken apart and cleaned the hydraulic gear pump and placed it back into operation ....and like before it seems to have good flow creating good pressure. Have not had the ability to test actual value of pressure. Moving on to the foot auxiliary valve I removed and inspected it thoroughly cleaned placed it back into the system. Miraculously everything seemed to work properly....I was elated. Unfortunately this was to be shortlived triumph. As I attempted to put it through its paces for first time the fuel shutoff solenoid had had enough and gave up. I literally had only been able to drive over to the test /work area when the fuel shutoff solenoid decided to protest and go on strike. Ok... so I fixed this and I attempted to put her through her paces and this time I rapidly lost function of the boom again for the up direction but the lowering of the boom does not seem to affected. I immediately parked the machine to do some investigating. This time however the foot auxiliary valve does not seem to have any affect on the raising of the boom. Instead cycling the hand control lever many many times which extended the lift cylinders by a fraction of an inch each time had finally allowed the boom cylinders to completely be extended where I have placed the safety in order to work on it with them in their extended state. Unfortunately when the fuel shut off solenoid died on me the boom was down and it was quite a task getting at the injector pump to remove the fuel shutoff valve. This happened in tall grass in a remote location at that time and I vowed that I must get the boom in the air so that I could work on it if it had any more problems. So now that I have it parked with the Boom in the air and on a concreted area I went through the entire machine and I fixed any linkage problems did all the adjustments to the linkage rods I even fixed safety items making sure that EVERYTHING lined properly and MOVED properly. Originally some areas were binding but all have been remedied. This however has not made any difference to the boom lifting. It lowers fine and also in its downward use will lift the front of the machine off the ground. Bucket seems to curl and dump well. It is only when I attempted to raise the boom that it only moves a fraction of an inch at a time for each motion of the hand lever in the up direction.

A little history of this is as follows.......prior to my obtaining this machine the previous owner hired couple of guys ho were mechanics but not diesel mechanics to fix this because the previous owner purchased a front mower / bruh hog attachment to be used with the 1840 but could not get the mower to operate at proper speed and would not lift either. Since they (the previous owner) could not get it to operate properly he sent it out to be repaired. They changed out the loader control valve with another used loader control valve. They spent many many hours trying to properly diagnose this but eventually gave up and returned the unrepaired machine to and shortly after I purchased it.
I intend on getting the books but have not been able to as of yet. PLEASE SOMEBODY HELP ME. THANKS
 

alrman

Senior Member
Joined
Jun 20, 2009
Messages
3,303
Location
QLD Australia
Occupation
Diesel Fitter;Small Business Owner;Cleaner
Welcome to HEF @Geoff Henderson

That's quite a saga!

Firstly, does the lever operation feel normal? Is there a neutral position? Can you feel spring tension as you operate the lever from neutral to the raise position?
Has the actual lift spool been looked at while someone is attempting to raise the boom? Is it moving?
Does the lift spool travel the same amount inwards & outwards?
How does the lift spool travel, compare to the crowd spool travel?

Does your machine have a single lap bar restraint or two separate ones?
There is a plate which prevents the operating levers from moving while the lap bar is in the raised position. Sometimes, if not adjusted correctly this can catch the levers & prevent full travel of the operating lever bellcrank. (see below)
Was this part of your adjustments to the safety items?

Have the lift cylinders ever been dismantled & checked/resealed?

By answering these questions you will give us something to work with.


1840controls.png
 
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