Mike: Congratulations and welcome. :thumbsup: :thumbsup: :thumbsup: As a new owner without knowing the history of the machine I recommend that you change all fluids as a good start. Refer to the FAQs and Operator Manual for the correct fluids and also recommendations on how to change fluids. :thumbup:

viewtopic.php?f=17&t=618

http://www.manuals.casecoltingersoll.co ... marked.pdf

viewtopic.php?f=27&t=694

:222: :446: Best Regards, Rich

 

Hi Mike. Thanks for joining our group.

Normally, my first reaction to any hydraulic problem would be to question the type of oil in the tractor. However, I'm sure that changing out the oil won't solve this problem. BUT......since this tractor is new to you and you have no history regarding maintenance, then conducting a thorough oil change is in order. As Rich stated above, go to the FAQ's section and find the document How to drain your hydraulic system on page 2 of the FAQ's.

Five gallon buckets of Rotella T 15W40 are available at some stores.

I believe that your problem lies with the pump.

In order for you to determine whether I am right or wrong, you are going to need a gauge like this one.

http://www.northerntool.com/shop/tools/ ... _200322889

It is 2 1/2" in diameter, glycerin filled and reads to 5000 PSI. You may be able to find one locally . In addition, you will need some fittings and about 4 feet of high pressure hose to connect this gauge to the drain port on the travel/lift valve that you will discover when you drain the hydraulic oil. With new oil in the system, you will be able to read how much pressure your pump can develop when it is asked to do so. The test is quite simple. Take the tractor outside and find an object that you know will not move if pushed by the tractor's bucket edge at ground level or slightly above. Place the bucket against that object and observe the gauge while pushing against that object with the throttle wide open. Try this a couple of times to verify your reading.

You should be seeing pressures in excess of 2000 PSI on that gauge. I think that you are not going to see half that amount.

A new pump will cost you around $225.00 or so. Not the end of the world when it comes to hydraulic pumps.

Questions???

 

thank you for the quick replies, I will do the oil change and I do know someone who deals with tractors of their own, so I should be able to get a guage.
I will post my findings might take awhile to get this done though, thanks agian. Mike

 

The time frame is in your hands, Mike.

IntroubleAllTheTime changed the pump on his 600 and positively loved the experience. I'm sure that he would be willing to fly to wherever you are and change your pump for you. :lol: :lol:

 

The time frame is in your hands, Mike.

IntroubleAllTheTime changed the pump on his 600 and positively loved the experience. I'm sure that he would be willing to fly to wherever you are and change your pump for you. :lol: :lol:

:rotflmao: :rotflmao: :rotflmao: :thumbsup:
Mike: If you end up changing the pump, please don't hesitate to PM me in addition to posting, could even talk over the phone. I'll share anything that could be helpful to you. Here is the thread in connection with my 646 hydraulic pump replacement for information purposes only (specs could be different on yours).
viewtopic.php?f=7&t=2038&hilit=changing+hydraulic+pump+646&start=10
:222: :446: Best Regards, Rich

 

thanks for all the advice and offers for help
I drained all of the fluid following the instructions given in a previous reply, refilled it with 15w-40 as suggested, i have to say it did help with the drive power, but it still doesn't have the guts i think it should have.
I cannot drive forward and raise the bucket or tilt the bucket up at the same time, in fact the bucket wants to lower if i try to raise it going forward,
I am going to ask a dumb question here, I am assume that I should be able to drive forward and tilt or raise the bucket up at the same time?
I can't really scoop up anything like it is now.
i am going to try and get the pressure gauge but i am pretty sure I will end up replacing the pump

 

Mike: Yes you should be able to move the bucket up and down and tilt while in motion. See what Tom and the group says at this point with the results of the fluid change. :thumbsup:
:222: :446: Best Regards, Rich

 

Because of power beyond in travel valve you need to move levers on loader valve with TCV in center position. And only use 20-50 motor oil in hyd. system are higher weight straight 50 is best Valvoline has weights up to 60 weight in my area NAPA stores have higher weight oil. Gear pumps quickly loose there tight fits so 15-40 works only when tractor is new condition.

My old 646 will get this 5qt. jug 20w-50 next 4qts. 80w-90 finish filling to full mark 20w-50 This what use up to 2 hour jobs like moving dirt full bucket loads with 400 ft. travel.

You bet that in pass these old loaders have starve for oil and no oil changes in pass and possible add gasoline in wrong tank.

The new system pick was 20w-40 on old system that needs changing 50 weight are higher because very high dollar to go back to new condition new pump and new drive motor we as owners save money and get work done just by changing oil weight with short money.

 

I read gator's post and I am struggling somewhat with his advice. As I see it, gator is suggesting a band-aid treatment for a real problem. Using a mix of 20W50 and 80W90 is his way of trying to stop the oil from bypassing inside the pump and the drive motor. No question that his will work. However, gator lives in Florida where temps are consistently pretty high. Try this fix in the northern states and you are going to have problems when the temps drop down to freezing or lower.

Without question, you could try this, if only to see what happens. If your pump and/or motor are well-worn, then performance will improve because flow and pressure will increase. However, my position is that it is always better to diagnose the true problem and fix that. The reason pumps fail is because owners fail the pumps by not changing the oil once each year like the manual tells them to do. Dirty oil wears out pumps and motors. Clean oil protects them. It's that simple.

You say that you changed the oil but did you follow the instructions in the FAQ document and drain all the cylinders on the loader? If you didn't, then you left a lot of that old oil in the system and polluted the new oil you just installed. At this point, I wouldn't worry about it. Buy or borrow the gauge and do the pressure tests. Make sure that the tractor and oil is running at operating temps before doing the test. Or.. run one test immediately upon starting the tractor and then leave the tractor running for 15 minutes and do the test a 2nd time. Record your results.

 

yes i did drain all of the cylinders, it was quite time consuming to do them all, but i felt it was worth the effort to be sure, i even pushed the cylinders in and out which removed a whole lot more fluid, it took the full 14 qts to fill it
I spent a whole lot of time reading all kinds of different forums, and that is the main reason I went with the 15w-40. I live in Northern Michigan.
thanks again for everyone's opinions and advice I appreciate it, this tractor and hydraulic stuff is all new to me. Mike

 

You haven't been clear on how much power you have in the drive system? When in high range will the tractor move easily up a modest grade? In low range can you spin the wheels pushing against something solid? If the answers are yes to these questions then you may simply need to adjust the relief valve in the loader circuits.

 

ok that gives me some hope, it goes up a grade good in hi and it will spin the tires in low when I was trying to move some rocks yesterday
it didn't move well when I got it, but i had a new banana plate made and have great travel in the travel control valve, full forward and reverse movement.
please explain more about the adjustment you mention, as I said this is all new to me. thanks a bunch Mike

 

ok that gives me some hope, it goes up a grade good in hi and it will spin the tires in low when I was trying to move some rocks yesterday
it didn't move well when I got it, but i had a new banana plate made and have great travel in the travel control valve, full forward and reverse movement.
please explain more about the adjustment you mention, as I said this is all new to me. thanks a bunch Mike

The pump feeds oil to all the hydraulic functions in the tractor however each function has its own relief valve that controls how much pressure can be applied to each function. Confusing?

If your tractor has a rear mounted hydraulic PTO valve, then the oil from the pump goes to this valve first. The relief that is inside that valve is set to open up at 2800 PSI, we'll say. From there the oil goes to the Travel/Lift valve and it has two reliefs in it. The first relief governs the pressure that the drive motor sees and that will be around 2600 PSI... less than the previous relief at the PTO. The second relief keeps watch on the lift circuit which sends oil to the mid -mount cylinder and the 3 point cylinder IF the tractor has one. That setting is perhaps 1000 PSI so that they cylinders are protected from damage and brackets/linkage etc are prevented from being bent. The Travel/Lift valve has a special port on the side of it called a Power Beyond Port that feeds some of the oil to the Loader Control Valve which also has its own relief that is set at 1200 PSI because that pressure is all that is needed to run the loader cylinders and meet the specifications for breakout force at the lip of the bucket as well as the amount of weight the loader will lift to full height.

It is highly unlikely that more than one relief has failed and it is unlikely that even one relief has failed but as Bart noted, it is something that must be investigated. However, that investigation needs to be done in proper sequence and with the use of a pressure gauge that is inserted into the system in the proper places to check the pressures on an individual basis. Obviously, if the pump is worn badly, that will affect EVERY individual circuit in the tractor's overall hydraulic system and therefore, determining the health of the pump is priority one.

BTW, do you have a rear PTO valve on this tractor?

 

yes it has a rear pto, this might be worth mentioning also, the tiller doesn't work, when you move the lever for it to the forward or reverse position you can see the lines flex from the pressure going in them, but the tiller doesn't work,
would this possibly have anything to do with my problem?
again thanks for everyone's help and suggestions.

 

I think that the tiller problem is unrelated. Assuming you have Quick Disconnects on your PTO lines, maybe one has failed and no longer will pass fluid through? Or something may be plugged? Your tiller motor or internal parts may be froze up I suppose. Can you get any movement out of the tines and shaft just by working them forward and back by hand? Just taking shots in the dark here...

 

yes i can move the tines by hand, in fact I am thinking the chain is broken, as I can turn the tines all the way around, i dont think i should be able to do that if the chain was intact.
I do have one strange coupling on the line, it is not a round ball like the others,
it has a point end inside it, hard to explain but it doesn't look right to me.

 

To "test" your QD's you could hook them together and run the PTO valve. If the lines flex a bunch and either the engine bogs down or you hear a "squeal" from the pressure relief in the PTO valve then you know there's a problem in the QD fittings. And no, the tiller shouldn't be easily turned by hand. I can push on the tines with all my weight and all I get is a VERY slow movement as oil slips through the hydraulicly locked motor.

Rob

 

If the chain on the tiller was broken, theoretically it would drop to the bottom of the chain case and jam the sprocket. You would not be able to rotated the tine shaft smoothly.

However, these chain case's are filled with grease, not oil so it's hard to give an absolute. A broken chain is certainly a possibility.

What is or is not going on with the tiller has no bearing on the issues you described previously. The sooner you get your hands on a test gauge the better. Now that I know you have a rear PTO... the testing becomes cheaper, simpler and faster.

The pump feeds oil directly to the rear PTO valve. Take the quick coupler off of tiller hose and adapt that coupler to the pressure gauge. Plug the pressure gauge into the mating quick coupler on the tractor. Start the engine and run it at full throttle. Use the lever on the PTO valve to open it in one direction and look at the gauge for movement. If no movement is noted, then instantly reverse the lever. Now... the gauge should be registering pressure. If you do not see 2000 PSI or more on the gauge, then it's time for a new pump.

 

getting the guage today, am I supposed to "T" this in line somewhere or just hook it to the end of a hose?
doesn't seem like i could use the tractor with on of the hoses unhooked.
thanks, mike

 

Remove one of the quick couplers from the TILLER.

Use fittings to adapt the gauge to that quick coupler.

Plug the quick coupler into the mating half coupler on the rear PTO VALVE.


Start the engine and run it at 1/4 throttle.

Move the PTO lever off the centre (neutral) position while watching the gauge.

If the gauge needle moves, then you have found the correct side of the PTO for the test. Move the handle back to neutral.

If the gauge needle does not move, then flip the handle to the opposite side of neutral and then when you see the needle move, put the lever back into neutral.

Then, run the engine at full speed.

Move the PTO handle back to the side that showed needle movement. Record the pressure noted on the gauge and return the lever to neutral.

Allow the tractor to run for 10 to 15 minutes until the hydraulic oil reaches operating temperature of at least 125 degrees F. You can use an oven thermometer to check this.. These are the ones with a sharp probe designed to be pushed into roasts. The Dollar Store has them.

Repeat the above test.

Cold oil should read higher than hot oil when the PSI is measured.

Post the readings back here in this thread.

 

In addition to Hydriv's test above I'd add the following...

Assuming this machine is equipped with mid-lift...

-Verify you have a TCV with Power Beyond and it is routed correctly

-Place axle in open/neutral with travel lever in center/neutral
-Move mid-lift lever fully to one direction until cylinder bottoms
-is relief opening?
-what is pressure measurement on gage?
-Same as above except mid-lift lever in opposite direction

-Place mid-lift in center position
-Move loader lift circuit in one direction until bottoms
-is relief opening?
-what is pressure at?
-Same as above but opposite direction
-Do the same for bucket circuit

 

Thanks for the directions, any testing will have to wait as the pto hose cracked, it must have been really bad as I hardly moved it.
I did not get the guage hooked up where I wanted to put it,
I got it on the hoses that used to go to the tiller and all I got was about 300psi or so.

 

If your tiller was NOT connected to the tractor in any way and you put the gauge at the end of a hose that is connected to the PTO valve, then it sounds as though you have it installed correctly. If the hose does not leak when you move the PTO lever to supply oil to that hose, then I wouldn't worry about the hose for the moment.

Did you run the engine at full throttle? If so and all you got was 300 PSI, then the pump must be shot. You should be seeing about 2600 PSI on that gauge if everything is working properly. Here is a replacement pump.

http://www.grainger.com/Grainger/wwg/se ... earch.y=10

 

ok, i had the gauge "T"d into the circuit if you know what I mean?
when I tilted the bucket all the way up or down until it stopped the gauge hit around 1200, i was going to "T" it into the PTO circuit but the braided hose cracked.
I really don't see any other area to hook the guage into without have some really special fittings
sorry if I sound dumb but this hydraulic stuff is all new to me. thanks for your input and advice. MIke

 

Yes.... I understand what you mean when you say you had it T'd into a circuit. When testing the pressure in the loader circuits, it's perfectly OK to install a Tee fitting on one of the lines going to a cylinder/s and then run that cylinder/s to the very end of its travel and keep applying the oil pressure. The loader has a relief valve that is supposed to pop at 1200 PSI so it sounds as though your pump can generate at least that much pressure. However, the pump FEEDS the rear PTO valve FIRST and that's the spot you want to test FIRST because that's where you will find out whether the pump is good or bad.

If you have two hoses leaving that PTO that go to quick couplers that are screwed onto the tiller, then remove one of those quick couplers from the tiller motor and then go to your local hydraulics store and get a fitting that will transition that coupler to the gauge. Then plug that gauge into the hose once you have replaced that hose.