case 3394 transmission

ok, i have been trying to figure out this tractor for some time now. to start from the beginning. i rebuilt all the power shifts. ran tractor and low transmission pressure light came on. preformed some checks per the repair manual. performed standby pressure check. was only getting 80 psi at idle and 150 at full throttle. put in a flow meter. fell on its face. had pump rebuilt. installed pump. ran. when cranking tractor over. would get the 350 psi. as soon as the tractor would start, pressure would drop to zero. drained all the oil and checked the inlet screen. had some fibers on it. cleaned all off. tried running again. same result, took pump back and had repair shop test. they said it was fine. they replaced the compensator valve just to try. no when cranking the needle bounces more while cranking but still drops to zero when starting. i tried plugging off the supply line for the gear pump. started tractor and had 350 psi while running. hooked up gear pump supply. started tractor and dropped to zero. took apart the brake valve mounted to left side of tractor. nothing found wrong. installed and started tractor with everything up normally. had my pressures for 15 seconds. took brake valve apart again. didnt see anything wrong. ran tractor again. didnt have my pressures again. i am not sure where to look next. any suggestions would help! Thanks ahead of time. Greg

I dont know if this will apply to you but the problems you are having is similar to the trouble I had when the clutches failed in my 1370. I rebuilt the PS and replaced everything i thought was bad. After I got it together with new/fresh oil it ran for a few minutes and I lost pressure.

My problem was this even though I replaced the oil there was so much spent fiber in the rear end it was plugging off my screen. I rigged up a air hose so i could clear the screen with air and i would have pressure until the screen plugged again.

Our local Case expert told me that at times he had to pull the rear pto housing off and clean the fiber from the rear end area.

In the end I had to pull the rear housing and clean it out. I jacked the tractor front end up in the air and blocked it in place and flushed with diesel to get it clean.

I originally cleaned the housing when I rebuilt the PS but it was amazing how much material remained. After all of the problems it finally stopped plugging the screen.

I dont know if this is your problem not but it sounds similar.

Thanks for replying. i did clean the inlet screen once already. i went removed the shifting plate on the right side, bent up a piece of copper and vacuumed the fibers off the inlet screen. put together and have less than 5 minutes of run time on it and still doing it. i even filtered all the oil going back into the tractor.

Greg I wish I had some ideas for you, but with almost no 94 series in my trade area I have very little experience to fall back on concerning problems like that. I wonder why your standby pressure is OK with the gear pump disconnected, that should be a major clue, Rod.

i know, i am lost and not sure where to check next. i pulled the filter head off before plugging off the gear pump, couldnt find anything there. after plugging the gear pump off. we hooked the pump back up and plugged off the line going to the brake pedals. nothing changed. hooked that line up, plugged off line going to the brake/steering valve under cab and blew the line going to the brake pedals. after that we took the brake/steering valve apart. didnt have anything jump out at us. i know it is nothing in the transmission because it still acts up when trying to do the standby pressure checks. i not sure what in the steering or brake system could loose that much oil. the only thing i havent tried yet was plugging off the line that goes from the gear pump to the filter head again. just dont wanna wreck anything doing that.

Did you check the charge pump pressure?

yes i did, before filters was 25 psi, after filters was 22 psi. after filters spec is a minimum of 10 psi.

Have you flo-metered the pump right on the tractor? Meaning checking pump output & dumping back to sump in the rearend housing, and not running any oil through the tractor hyd system other than the charge & piston pump.Email is open

You may want to look at the compensator valve on the pump, it controls the flow depending on the load. I ran into one that failed on a 2290

MY 2394 HAD ABOUT THE SAME PROBLEM... I ENDED UP SLITTING THE TRACTOR TO GET THE BIG SUCTION SCREEN OUT.. IT WAS 3/4'S PLUGGED... REPLACED THE $109. SCREEN AND HAVE NOT HAD AN ISSUE SINCE...OTHER THAN THE 14 HOURS OF MY LIFE I WILL NEVER GET BACK TO DO IT.. YOU HAVE PRESSURE AT STARTUP FOR A FEW SECONDS SO OIL IS THERE BUT IT SOUNDS LIKE YOU RUN OUT OF IT QUICKLY..I LEAN TOWARDS RESTRICTION ..ON MY 2290 I ENDED UP REPLACING THE PUMP COMPINSATOR VALVE... THEY ARE NOT CHEAP. IF YOU GO THERE ..HANG ON.. NH

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