Pasquali steering frozen ??

   / Pasquali steering frozen ?? #1  

mpilihp

Silver Member
Joined
Apr 8, 2009
Messages
216
Location
Jefferson, ME
Tractor
Pasquali 988
I went to get my plow set up on my 988 Pasquali and I discovered I cannot steer it. The steering wheel is frozen still, I just used it last week but it was above freezing so im assuming it is frozen by ice and not rust/corosion. Other hydraulic items work such as 3pt and FEL. So my question is how does the steering work, is it the steering box thats frozen with water in it or is it the lines to/from the steering hydraulic rams that are frozen?

Anyone familiar with how Pasqualis steer know how to reslove this? IE I am assuming I need to warm it up and remove the moisture, but from what and how.

THank you

~ Phil
 
   / Pasquali steering frozen ?? #2  
Hi Phil, The Pasquali's use a Danfoss steering valve for power steering. Your two rams are lower than the valve though and since water is heavier than oil, you may have condensation / moisture accumulation in either, or both components. It's not uncommon for certain hydraulic components to freeze up during the winter, some designs are worse than others. Normally the sure bet is on a hydraulic "float" valve mounted in a vertical position. Water gets into the system, settles out in the pocket of the spool and freezes so that you can't move the lever. Horizontal mounted spools give fewer problems. In the case of your Danfoss steering valve, they are a mono-block type valve with orifices (input / output), kind of a rotory deal. The easiest way to get things going (besides the garage for 24 hours) is with a hair dryer, ensuring you don't overheat components. If you keep touching what you are heating, stop when it gets "warm" to the touch. It doesn't need much. Once you get things flowing and warmed up, check your hydraulic fluid for any moisture contamination. If "milky" or a light, opaque brownish color, the oil will need to be drained and replaced. You may need to do this a couple of times to remove all of the contamination. On the 988 you often see a Bosch regulator in the power steering circuit (on the return side). This moderates pressure to ensure the power steering isn't lost when working a loader. You will want to warm this also if the others don't seem to be doing it for you. Bottom line is don't heat components until they are hard to touch. This can damage seals. Wish there was an easier answer. All the best, Tom
 
   / Pasquali steering frozen ??
  • Thread Starter
#3  
Hi Tom thanks, so once I get it freed up and in the garage. Where do I drain the system from and anything special need to be done when filling to remove the air.

Thanks
Phil
 
   / Pasquali steering frozen ?? #4  
The best place to drain is the lowest point in the system. Some Pasquali's had drain plugs plumbed into a line (a simple iron "T" fitting, others did not. Steering cylinders can have the lines detached and pumped by hand to empty. No worries about air in the system. You fill it full and should be able to cycle the hydraulics until you hear the bypass kick in, then the other direction. Add fluid as needed. Once you flush it through, you might find contamination in the oil again - working it's way out of the nooks and crannies. Pasquali calls for a fluid change at 1000 hours. This would be for a high use machine. For occasional use tractors, 500 hours should call for a change, but it never is. Most of these tractors live outside and can go 30 years or so before they reach 500 hours, so by that time the moisture build up is bad. Anytime you see oil contamination, it is best to change it out. It is cheap insurance.
 
   / Pasquali steering frozen ??
  • Thread Starter
#5  
So I drained the hydraulic system including the holding tank. I also drained the steering rams and then refilled the system. I found the hydraulic fluid looked good, not milky at all. Left it outside and again the steering froze. Tinkering with it I found applying heat to the steering column just below the steering wheel freed up the wheel. THis indicates to me that the steering shaft is freezing and not the Danfoss valve. I pulled the wheel off to find a sealed bearing at the top of teh shaft. The C clip that should be holding the bearing in was bent, twisted and half out of its ridge. The top of the steering column where the bearing is held in is bent up and the bearing probably will not come up. This shaft assembly is held on at the base by 4 hex bolts to the Danfoss valve. Im not sure what will happen when I take the steering column off, IE will it expose the inside of the valve and will allow hydraulic fluid to come out? THis is what it looks like:

Jefferson-20121227-00177_zps3e4ad985.jpg


Im thinking I will need a replacement steering column assembly as I dont think I can take the bearing out. Any thoughts?

Thanks

~ Phil
 
   / Pasquali steering frozen ?? #6  
I would think Phil that there would be a spline connection between the steering-shaft itself & the danforth valve. Not that it's any fun to get to, with the outer column welded to the plate & attached at the king-pin. The only way I see that bearing coming out is by removing the column, maybe the inner shaft would stay in place. Then you could use a piece of pipe, the same diameter as the OD of the bearing & drive it out, from the other side. A little heat on the outer column near the bearing may loosen things up, but don't go crazy with the heat, you could crack the column.

Shadow
 
   / Pasquali steering frozen ??
  • Thread Starter
#7  
Hi thanks yeah I think it will take a while to repair so Ive parked it outside and will pull the steering column off when its warmer and cover the tractor up. Im thinking Ill bring the column in to my local mechanic and let him replace the bearing he has a press and better tools than I.

THanks ~ Phil
 
   / Pasquali steering frozen ?? #8  
Yeah, I here ya on the repair it when it's warmer philosiphy!
Gotta tear down the nose of my machine in spring & repair/replace stator, or convert it to a modern alternator. Wrap her up good, it's cold & blowing good down here in Western Mass, so I imagine it's even colder up there in Maine!

Shadow
 
   / Pasquali steering frozen ?? #9  
Hi Phil, I think your column will be fine from the picture. You may find it a bit of a challenge to get the bearing out, but once it clears, you should be able to press a new one in or simply tap it in with a proper tool. The bearing is not critical to the operation of the steering, it simply centers the shaft and keeps it turning. A bronze or delrin bushing would work just as well, but that bearing is more than likely a 6304 and should be an easy find. Some columns use a double needle bearing arrangement, but normally it's an either / or situation. If the bearing is frozen in the column and you can get your shaft out, you can nip the inner race with a torch and break out the balls and race. Then if you run a small bead (about an inch) of weld on the inner surface of the stuck race (one or two places), it will shrink and fall out. You aren't looking at a bad job there, but it certainly is easier with a press. The press will also work nicely to reshape it a bit, as long as you don't over do it. Tom
 
   / Pasquali steering frozen ?? #10  
Hi again Phil. One other thing. Please note there is a bushing around the shaft and in the center of the bearing. Part 886.104.0 - you want to keep that intact and use it again if possible (just in case you cut the inner race). Tom
 
 
Top