763F no lift when cold

   / 763F no lift when cold #1  

bob763f

New member
Joined
Jan 15, 2018
Messages
9
Location
Doswell
Tractor
Bobcat 763F & Massey Ferguson 1233
This is my first post in this forum. A month ago I purchased a "new to me" bobcat 763F. It has 2500 hours on it. About a week ago the machine stayed outside over night and the temp got down to 15*F when I came out in the morning the machine started with no issues, pulled lap bar down and pushed the unlock button. The machine will move forward and backwards and bucket will tilt in both direction but will not lift. When you move the lift pedal you can hear the engine get a load on it and hear the line pressurize but it wont lift. After letting run and warm up for about 15 min everything worked fine and no more issues. This morning we 17*F and I have the same issue. I have done some research all over youtube and google and not finding any help. The machine does not have the boss system, it is handles and foot pedals, it has a new hydro filter and good clean fluid that is topped off. Any help or guidance is appreciated.
 
   / 763F no lift when cold #2  
Bucket function works OK so that eliminates the gear pump and normal open center flow through the valve. When you step on the lift pedal to raise does the pedal move easily to full stroke or is it very firm? If it is firm/stiff just moving from neutral position then I suspect the Float Positioning spring assembly on the back end of the lift spool has moisture in it and freezing up.
 
   / 763F no lift when cold
  • Thread Starter
#3  
It doesn't feel any different. It has the same movement and feeling when its is actually working. Not stiff or jammed up feeling. Doesn't feel like anything is frozen. Actually feels just like the the other side that is working.
 
   / 763F no lift when cold #4  
If pedal is moving full travel and the lift valve spool is moving in and out with the pedal then only thing I can think of that would possibly freeze is the check valve of the BICS for the lift spool. When you press the unlock button to unlock the valve a single solenoid on the valve opens to allow charge pressure oil to flow to 2 individual check valves ( 1 for lift & 1 for bucket tilt). Possibly some moisture in the return spring area behind the check valve that is holding it seated in place until oil warms enough to melt it.
 
   / 763F no lift when cold
  • Thread Starter
#5  
Any chance you have a photo of what your describing? I will look on the web now as well.
 
   / 763F no lift when cold #6  
If pedal is moving full travel and the lift valve spool is moving in and out with the pedal then only thing I can think of that would possibly freeze is the check valve of the BICS for the lift spool. When you press the unlock button to unlock the valve a single solenoid on the valve opens to allow charge pressure oil to flow to 2 individual check valves ( 1 for lift & 1 for bucket tilt). Possibly some moisture in the return spring area behind the check valve that is holding it seated in place until oil warms enough to melt it.
This was my thought as well 😊
 
   / 763F no lift when cold
  • Thread Starter
#7  
I tried it this morning with a temp if 26*F and everything worked fine. It seems to be a matter of how cold it is rather then if its below freezing or not.
 
 
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