slow, rachetty, inadequate hyraulic action

[Larryboy]

I have an '87 Case/IH 385 Dsl Utility tractor (about 1750 hours). Recently discovered leaking hydraulic filter at sealing surface. Replaced filter and brought fluid level back up. Hydraulics operated very slowly and jerky after the filter replacement. Thought it might be air in the system, and that the air would work out of the system. Well, the slow and jerky action has worsened. The tractor will not keep the front loader bucket up, run the bushhog mower and steer properly (power steering). I need help with troubleshooting this problem, please. Any thoughts and suggestions would be appreciated.

 

[TedLaRue]

You are describing the classic symptoms of either low hydraulic fluid level, or (in your case more likely) a clogged strainer (screen).

If your loader won't stay up, then the seals in the hydraulic cylinders need replaced (not a surprise after 1750 hours). The failing seals probably clogged your strainer causing your other problems.

The strainer is a very fine screen type filter separate from your hydraulic fluid paper-type screw-on filter. When seals in hydraulic cylinders wear, the rubber bits and pieces accumulate on the strainer and will cause your hydraulic pump to starve for fluid. That makes hydraulics jerky and power steering (which is hydraulic) jerky or non-existant. The strainer can be removed, cleaned, and then replaced.

I can't explain why you noticed this after replacing the filter, but it may have been that you started paying closer attention then.

I'd recommend replacing the seals on the loader cylinders first. Otherwise you'll just clog the strainer again. You can replace the seals yourself or take the cylinders to a shop. Search this site (TBN) and you'll find a lot of other threads about rebuilding cylinders.

You may have to clean the strainer two or even three times before you have filtered all of your hydraulic fluid.

EDIT: Oh, and I have no idea how this would relate to your brush hog.

 

[Larryboy]

Thank you, sir, for your analysis and recommendations. And, actually, the front loader had, prior to the filter change, had had a very slight loss of "staying put-ness". I will certainly take your advice on the action recommendations. This will be my first bit of mechanicing on the tractor. Oh, any idea how to know which of the two front loader cylinders is the offender? Also, if the hydraulic hoses are generally in less than pristine condition, e.g. numerous small surface cracks, should I do a wholesale hose replacement (considering, as you say, the hours accumulated)?

The bushhog issue: I assumed that the PTO worked off the hydraulic system and was perhaps starving the other components

Also, I have an I&T Shop Service booklet "CASE/INTERNATIONAL SHOP MANUAL" NO. C-39 with approximately fifteen pages of hydraulic details. Would you (or anyone else) recommend getting a more detailed manual (something like a Chilton or Haynes for cars), especially considering my low level of expertise?

Again, THANKS for the reply !

 

[TedLaRue]

If your loader is drifting down under its own weight, you need to have both of the lift cylinders rebuilt.

Note: If it drifts down a couple of feet in 24 hours, I wouldn't worry about it, but if it drifts down while you watch, then you probably need a rebuild.

As for your "less than pristine" hoses, you could probably buy one replacement hose of each type. Then when an old hose goes, replace it with a new one. Or if you want to splurge, replace them all now. Loader hoses take a beating.

I do my own work on my tractor, truck and cars, so I buy the service manuals when I buy the vehicles. A good manual can encourage you to take on more complicated repairs if you have the time and tools.

 

[Larryboy]

Thanks for the additional advice. Yep, the bucket drops noticeably now!

I thought I had searched for an "official" Case/IH service manual (1987 Case/IH 385 Dsl 2 wheel drive, PIN B020148), without success. I purchased the tractor not too long ago, and like to think that I will keep the old tractor and keep it running "myself". So, thanks for the encouragement. I'll search further. I think I have noted that there is an early '87 model and a late '87 model. Would you know how I can determine which one I own?

Again, thanks again

 

[3RRL]

What shape is loader VALVE in? Perhaps a couple "O" rings in it blew? That may be the problem if your loader is leaking down and some of the "jerkiness" too.

 

[JerryG]

Before you go spending money that doesn't need to be, do some troubleshooting. You don't know if the cylinder packing is bad or not. First find out if there is a suction filter (screen) that needs cleaning. If it is plugged it will cause problems like some you are having. If you check that out and it is clean or cleaning it doesn't help let us know.
As far as the checking on hoses go, that is no problem. The only reason the rubber is on the outside of the hoses is to protect the wire brad from damage. They can have checks and cracks all over them and still be fine.
It is normal for a loader to drift. Some companies even print drift amounts that are allowable. They are usually more than what I would like to see but they are still considered normal.

 

[Soundguy]

While your hyd cyls may or may not need resealing.. i'd think your spool valves may need to be tested for leaks as well.

As another poster stated.. sounds like low fluid ( and / or cavitation ) could be more air entrainment from a suction side leak.. clogged filter.. or a pump that gave up the ghost from any of the above listed reasons.

soundguy

I have an '87 Case/IH 385 Dsl Utility tractor (about 1750 hours). Recently discovered leaking hydraulic filter at sealing surface. Replaced filter and brought fluid level back up. Hydraulics operated very slowly and jerky after the filter replacement. Thought it might be air in the system, and that the air would work out of the system. Well, the slow and jerky action has worsened. The tractor will not keep the front loader bucket up, run the bushhog mower and steer properly (power steering). I need help with troubleshooting this problem, please. Any thoughts and suggestions would be appreciated.

 

[elad]

Seems most of your troubles started after the filter change.
Maybe you got a bad filter that is causing problems. Might
be worth trying another new filter. Just a thought.
Good Luck
elad

 

[Larryboy]

Thanks for all the analyses and recommendations I am going to take the easiest immediate action of adding fluid Neither the owner's operation manual nor the dipstick gives information on exactly where the proper level is If the problem does not clear with the addition of fluid, then I will start un-doing things Again, thanks to all for the responses I will post my progress...