Help with hydraulic drive

9323 Views 61 Replies 8 Participants Last post by gator_rider2, Jan 13, 2012

case680rob

Discussion Starter · Jan 5, 2012

In an attempt to get the best performance out of my 190, I read in the service manual that a pressure test will tell me the condition of my system. So I installed a gauge (0-3000psi) between the pump and the PTO valve body, right where I can see it, on the left fender.

Some questions I know will be ask about my situation:

Recommended pressure per the book: 1250-1500 psi

Oil stats: 20-50, changed and screen cleaned about 50 run hours ago

Intended use of the tractor: tilling, dump trailer towing, front blade dirt work.

For the test, I warmed up the tractor by using it as I normally would. Let the engine idle for a minute or two, throttle up to 1/3 and go find something to till up. As I worked, both tilling and pushing with the blade, I watched the gauge. This is what I saw.

Tilling, avg 800, peak 1000 with audible releif valve actuation (squealing)

Dozer work, low range, avg 700 peak 1075 - Peak pressure read as tractor comes to a stop against plowed up dirt, pressure does not increase after tractor stops.

Flat ground travel, low range, avg 550 peak 800

Flat ground travel, high range, avg 700 peak 950

The test was done with both cold and warm oil temp, but numbers were not different enough to post. The numbers above were recorded with warm oil and full throttle setting.

Given the numbers, I think my next step should be to adjust the travel releif valve to around 1300 or so, this should give my tractor greater ability to tow the loaded dump trailer and to push dirt.

Here's where I need some help. I'm not all that familiar with the hydraulic drive systems of these tractors, but I KNOW that many on this site are well versed in this. I don't expect to find a fix-all answer here, I know this could get complicated.

My tractor has PTO valve, Flow Control Valve, and attached tiller.

Could any of these components be responsible for the loss of pressure? Should I check for a worn or cracked travel valve?

Any help here would be appreciated, so thanks ahead of time!

Rob

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gator_rider2

· #2 · Jan 5, 2012

viewtopic.php?t=3974

Your test shows that spring have settled in reliefs there constantly under load and springs looses its force over time.

Now you have to bring up force spring Items 4 through 10 page 37 in this link http://www.manuals.casecoltingersoll.co ... marked.pdf the older relief used shims to adjust. For shims back in day I used Dimes ,Nickels, and Penny's according size needed. Double springs one will brake other be good so good to check.

I think PTO valve same as travel valve on 190 tractor as for relief setting inside valve.

1300 psi should wake up hydraulic's on tractor with 12 hp engine 1300 psi work engine.

Hydriv

· #3 · Jan 5, 2012

case680rob said:
In an attempt to get the best performance out of my 190, I read in the service manual that a pressure test will tell me the condition of my system.

A pressure test is an important indicator of the health of the hydraulic pump. Case made a "Hydra-Sleuth" available to its dealers that not only checked pressure but it also checked oil temp and oil flow.

So I installed a gauge (0-3000psi) between the pump and the PTO valve body, right where I can see it, on the left fender.

I am assuming that you located the hose that leaves the hydraulic pump and goes directly to the IN port on the fender-mounted PTO/FCV. And then you installed a Tee fitting on that IN port to accept the gauge.

Some questions I know will be ask about my situation:

Recommended pressure per the book: 1250-1500 psi

You do not state which book you are referencing. Presumably, you are relying on the copy of the 150/190 Service Manual you have. As you know, we don't have that here..........yet. :lol: This book

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

has a chart on Page 5 that shows the Relief Valve Specifications. The relief in the Travel Valve is supposed to begin opening at 1500 PSI plus or minus 50 PSI but it will go wide open at 1600 PSI plus or minus 50 PSI. In other words, if you did not have the optional PTO/FCV valve on your tractor, you should see 1600 to 1650 PSI on the gauge with the throttle wide open, the rear wheels NOT spinning and the Travel Valve pushed fully forward to deliver max oil flow to the wheel motor. The fact that you have the optional PTO should change that pressure reading to 1700/1750 PSI because the system would now rely on the relief that is built into that PTO to protect the pump from damage. It is customary for the FIRST relief in an open centre hydraulic system to have the highest setting. The reliefs that follow after, will be set slightly lower. As Gator stated in his reply, relief springs do lose tension over time due to always being under compression in a hot environment.

Perhaps your Service Manual/Hydraulic section shows the PTO/FCV valve. If so, that would be very helpful. If not, then that is a problem. :lol: The easiest way to explain it is to send you to this manual

http://www.manuals.casecoltingersoll.co ... marked.pdf and have you examine pages 36 and 37. The ITEM numbers 4 through 10 make up the relief valve in the Travel Valve. In this instance, two springs are used. I have no idea if the PTO/FCV used one or two springs in its relief. However, you can see that a SHIM WASHER is used (Item 6) to put additional pressure on the two springs just as Gator mentioned. Gator would have been working on much larger valves in order to use coin of the realm as shim stock. :lol: Here's the dilemma you face. It MAY be that your problem is with weak springs in the relief and replacing those springs would solve it or shimming those springs would solve it. Then again, it MAY be that your pump is just worn out and is not capable of developing enough pressure to force the relief in the PTO to open up. That's where the test using the grease gun comes in because a hand operated grease gun will give you absolute control over the amount of pressure going into the PTO valve as the gauge is being observed. The pump cannot be damaged by over pressuring it because the pump is not connected while this test is performed.

No wants to throw money in the wrong direction if it can be avoided. However, you are the current owner of a 46 year old tractor that is showing a very low pressure reading. Logic tells me that there is a much greater probability of your pump being worn out than there is for the relief springs to lose that much pressure due to sacking. If you have more time than money available, then you could CAREFULLY take the relief in the PTO apart, making sure that you drop nothing and also note the ORDER in which things leave the body. If you have a local hydraulic repair shop that knows their stuff, they will have shims of different thicknesses available. You could add one or two shims and then test the system again to see if a higher reading is noted. If so, then keep adding shims until the ideal pressure is reached. The alternative is to just spend $250.00 and buy a brand new pump. Stick it in, run the test again and see what the results are. My guess is that will solve your problem but I could be wrong.

Oil stats: 20-50, changed and screen cleaned about 50 run hours ago

Intended use of the tractor: tilling, dump trailer towing, front blade dirt work.

For the test, I warmed up the tractor by using it as I normally would. Let the engine idle for a minute or two, throttle up to 1/3 and go find something to till up. As I worked, both tilling and pushing with the blade, I watched the gauge. This is what I saw.

Tilling, avg 800, peak 1000 with audible releif valve actuation (squealing)

Dozer work, low range, avg 700 peak 1075 - Peak pressure read as tractor comes to a stop against plowed up dirt, pressure does not increase after tractor stops.

This is the test that tells the story. Your highest reading was 1075 PSI when it should be up around 1700 PSI. None of the other tests you did are asking for the pump to work as hard as it possibly can.

Flat ground travel, low range, avg 550 peak 800

Flat ground travel, high range, avg 700 peak 950

The test was done with both cold and warm oil temp, but numbers were not different enough to post. The numbers above were recorded with warm oil and full throttle setting.

Given the numbers, I think my next step should be to adjust the travel releif valve to around 1300 or so, this should give my tractor greater ability to tow the loaded dump trailer and to push dirt.

Here's where I need some help. I'm not all that familiar with the hydraulic drive systems of these tractors, but I KNOW that many on this site are well versed in this. I don't expect to find a fix-all answer here, I know this could get complicated.

My tractor has PTO valve, Flow Control Valve, and attached tiller.

Could any of these components be responsible for the loss of pressure? Should I check for a worn or cracked travel valve?

Any help here would be appreciated, so thanks ahead of time!

Rob

Rockdog

· #4 · Jan 5, 2012

Why would the system relief pressure be at 1700+/- psi if the PTO was not restricted?

Sounds like there's a relief valve that is cracking at 1000 psi and it isnt supposed to (my guess is its the PTO because without the the PTO engaged the unit apparently doesnt crack a releif at 1075 psi). I'd verify the relief valve settings before I did anything else.

Hydriv

· #5 · Jan 5, 2012

Where in the OP's post is the number 1700?

Rockdog

· #6 · Jan 5, 2012

Hydriv said:
case680rob said:

In an attempt to get the best performance out of my 190, I read in the service manual that a pressure test will tell me the condition of my system.

A pressure test is an important indicator of the health of the hydraulic pump. Case made a "Hydra-Sleuth" available to its dealers that not only checked pressure but it also checked oil temp and oil flow.

So I installed a gauge (0-3000psi) between the pump and the PTO valve body, right where I can see it, on the left fender.

I am assuming that you located the hose that leaves the hydraulic pump and goes directly to the IN port on the fender-mounted PTO/FCV. And then you installed a Tee fitting on that IN port to accept the gauge.

Some questions I know will be ask about my situation:

Recommended pressure per the book: 1250-1500 psi

You do not state which book you are referencing. Presumably, you are relying on the copy of the 150/190 Service Manual you have. As you know, we don't have that here..........yet. :lol: This book

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

has a chart on Page 5 that shows the Relief Valve Specifications. The relief in the Travel Valve is supposed to begin opening at 1500 PSI plus or minus 50 PSI but it will go wide open at 1600 PSI plus or minus 50 PSI. In other words, if you did not have the optional PTO/FCV valve on your tractor, you should see 1600 to 1650 PSI on the gauge with the throttle wide open, the rear wheels NOT spinning and the Travel Valve pushed fully forward to deliver max oil flow to the wheel motor. The fact that you have the optional PTO should change that pressure reading to 1700/1750 PSI because the system would now rely on the relief that is built into that PTO to protect the pump from damage. It is customary for the FIRST relief in an open centre hydraulic system to have the highest setting. The reliefs that follow after, will be set slightly lower. As Gator stated in his reply, relief springs do lose tension over time due to always being under compression in a hot environment.

Perhaps your Service Manual/Hydraulic section shows the PTO/FCV valve. If so, that would be very helpful. If not, then that is a problem. :lol: The easiest way to explain it is to send you to this manual

http://www.manuals.casecoltingersoll.co ... marked.pdf and have you examine pages 36 and 37. The ITEM numbers 4 through 10 make up the relief valve in the Travel Valve. In this instance, two springs are used. I have no idea if the PTO/FCV used one or two springs in its relief. However, you can see that a SHIM WASHER is used (Item 6) to put additional pressure on the two springs just as Gator mentioned. Gator would have been working on much larger valves in order to use coin of the realm as shim stock. :lol: Here's the dilemma you face. It MAY be that your problem is with weak springs in the relief and replacing those springs would solve it or shimming those springs would solve it. Then again, it MAY be that your pump is just worn out and is not capable of developing enough pressure to force the relief in the PTO to open up. That's where the test using the grease gun comes in because a hand operated grease gun will give you absolute control over the amount of pressure going into the PTO valve as the gauge is being observed. The pump cannot be damaged by over pressuring it because the pump is not connected while this test is performed.

No wants to throw money in the wrong direction if it can be avoided. However, you are the current owner of a 46 year old tractor that is showing a very low pressure reading. Logic tells me that there is a much greater probability of your pump being worn out than there is for the relief springs to lose that much pressure due to sacking. If you have more time than money available, then you could CAREFULLY take the relief in the PTO apart, making sure that you drop nothing and also note the ORDER in which things leave the body. If you have a local hydraulic repair shop that knows their stuff, they will have shims of different thicknesses available. You could add one or two shims and then test the system again to see if a higher reading is noted. If so, then keep adding shims until the ideal pressure is reached. The alternative is to just spend $250.00 and buy a brand new pump. Stick it in, run the test again and see what the results are. My guess is that will solve your problem but I could be wrong.

Oil stats: 20-50, changed and screen cleaned about 50 run hours ago

Intended use of the tractor: tilling, dump trailer towing, front blade dirt work.

For the test, I warmed up the tractor by using it as I normally would. Let the engine idle for a minute or two, throttle up to 1/3 and go find something to till up. As I worked, both tilling and pushing with the blade, I watched the gauge. This is what I saw.

Tilling, avg 800, peak 1000 with audible releif valve actuation (squealing)

Dozer work, low range, avg 700 peak 1075 - Peak pressure read as tractor comes to a stop against plowed up dirt, pressure does not increase after tractor stops.

This is the test that tells the story. Your highest reading was 1075 PSI when it should be up around 1700 PSI. None of the other tests you did are asking for the pump to work as hard as it possibly can.

Flat ground travel, low range, avg 550 peak 800

Flat ground travel, high range, avg 700 peak 950

The test was done with both cold and warm oil temp, but numbers were not different enough to post. The numbers above were recorded with warm oil and full throttle setting.

Given the numbers, I think my next step should be to adjust the travel releif valve to around 1300 or so, this should give my tractor greater ability to tow the loaded dump trailer and to push dirt.

Here's where I need some help. I'm not all that familiar with the hydraulic drive systems of these tractors, but I KNOW that many on this site are well versed in this. I don't expect to find a fix-all answer here, I know this could get complicated.

My tractor has PTO valve, Flow Control Valve, and attached tiller.

Could any of these components be responsible for the loss of pressure? Should I check for a worn or cracked travel valve?

Any help here would be appreciated, so thanks ahead of time!

Rob

Click to expand...

Up there^

Hydriv

· #7 · Jan 5, 2012

RD,
I see your point.

If he wants to test the pressure of the pump, all he has to do is disconnect the tiller's quick couplers from the tiller, make sure that the FCV is not bypassing any fluid and then engage the PTO. The full flow of the pump will then be dead-headed against the quick coupler, thus forcing the PTO's relief valve to open. The gauge will show one of two things. You will either see the amount of pressure that the relief is set at OR you will see the max amount of pressure that pump can build. If it turns out to be 1075 PSI, then more likely than not, the pump is worn so badly, it can't build enough pressure to open the PTO's relief.

case680rob

Discussion Starter · #8 · Jan 6, 2012

This is gonna take some time...

Saw the Hydra-sleuth in the Service manual, don't have one. I wish, I'd even share it with the others if I did.

The TEE fitting-yes, located between the first line from the pump and the PTO valve.

THE BOOK: yes, my Genuine CASE Service Manual for 150-190 and T90 Compact Tractors. :sidelaugh: I'll get that to y'all soon enough. Yes, that's where I'm referencing the 1250-1500psi.

Next book referenced, Parts Catalog A977 for 150-190. I have that too.

Spinning wheels? Really? Not my tractor :sidelaugh: Not unless I'm parked on a big slick rock or a soggy piece of lumber. Not even in deep mud... It just hooks up.

PTO/FCV notations in the Service manual, nope. However, I do have the E70 tiller book, which shows the PTO valve alone, no FCV... Darn, I think the FCV has a releif valve too.

Shim stock...Will the right diameter flat washer work? I have BOXES of nuts bolts and washers and such.

Grease gun? Never heard that one before, but I like it. Do I need to use motor oil in it or will grease be ok mixing up in the HYD system?

Rockdog said:
Why would the system relief pressure be at 1700+/- psi if the PTO was not restricted?

Sounds like there's a relief valve that is cracking at 1000 psi and it isnt supposed to (my guess is its the PTO because without the the PTO engaged the unit apparently doesnt crack a releif at 1075 psi). I'd verify the relief valve settings before I did anything else.

That's the squeal I hear, and it's coming from the PTO valve. I've listened to it many many many times, whenever the tiller gets hung up on a root or big rock. I can actually stop the tiller by doing this. I am leaning toward that being the first place to look.

Hydriv said:
all he has to do is disconnect the tiller's quick couplers from the tiller

Sorry guys, don't have those. It's on my list of things to buy. Pipe plugs will have to work, I'll get some.

Pump test... Should I do this bofore or after the grease gun test? And if the pump is bad, is there such a thing as a rebuild?

Something else that should be noted; I am the only one in the last 10+ years that has changed the oil in the Hyd system. For that matter, it may have never been changed since about 1969. That's when my Grandparents bought it. They are owner #2. From there it went to my Great Grandparents, owner #3, where it served ONLY as a mower and cart puller on flat ground, and that stretch was probably 25+ years... There is a possibility of 35 years worth of non-oil changing in there, and very little maint. on the whole tractor other than belts, engine oil, spark plug, and air filter. When I changed the oil this past spring the tractor went from hardly able to go up ANY hill in Low to cruising up hills in High. And performance has not dropped since. Just a bit of history I thought would be useful.

Thanks guys, this is all more than I had considered...

Rob

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Rockdog

· #9 · Jan 6, 2012

Sounds to me like you have your answer to the PTO relief setting and ability to crack it. You can do a manual check (port-a-power type hand pump using the same fluid your using in your hydraulic system) on the TCV relief crack pressure.

I'd first try a system performance / pressure test in reverse.

Pressure still not good then I'd do what Hydriv said regarding limiting the bypass of the flow control by plugging the return to tank port and carefully check the pump pressure by slowly slowly cutting off the flow (if the pressure gets up to the 1250 - 1500 then open it up right away). You'll know the performance of your pump right away doing that but be careful no to let the pressure get too high if in fact it is able. I dont believe there's a relief in that flow control valve. If there is then you'll know approximately what its set at.

Also should verify the pump is the correct displacement. If it isnt then everything discussed is for nought. Sounds like your pretty sure its original but you never know.

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bhildret

· #10 · Jan 6, 2012

Rockdog said:
Sounds to me like you have your answer to the PTO relief setting and ability to crack it.

Just a thought on the element of PTO valve relief causing the issue.

I don't have the 190 hydraulic diagram and I suppose it may be different than later PTOs. However, the later PTOs, being strictly in series and upstream of the TCV, really should not be able to cause this pressure loss at the TCV circuit. It could contribute to insufficient power on the tiller (running off the PTO), and result in the Tiller stalling out too easily.

However, since the relief pressure simply feeds to the downstream TCV, the PTO relief is only in play if the PTO valve is engaged(running an implement), then with a closed PTO, you can get full pump pressure input to the TCV. If the PTO is engaged, then it may relieve too early and dump pressure to the TCV, stalling the tiller, but not limiting the downstream pressures. That high pressure, relieved oil is still going downstream at something in excess of the relief pressure.

FLOW may be greatly restricted, which is what runs up the pump pressure to begin with ... a resistance to flow ... or said differently, a demand for power.

Given there is a verification of pressure not high enough, as measured between the PTO and TCV, I fully agree that something is amiss ... I just don't think it could be at the PTO (unless this early style PTO relieves to the return side of the hydraulic system).

I suppose it is possible the flow control is contributing. By design, it is not supposed to affect the system pressures, but rather only relieves downstream flow at the demand pressure (it is pressure compensated)

My thought on the PTO, or am I missing something?

Brian

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Hydriv

· #11 · Jan 6, 2012

My understanding is that any relief valve that is upstream of a motor or cylinder will limit the pressure in the system to the extent of the relief setting. In other words, let's say that the relief on a PTO valve is set at 2000 PSI and the relief on the Travel spool is set at !900 PSI. If the travel motor is stalled out and stopped while pushing a load of dirt with a blade, the pressure in the system will rise rapidly until a relief valve is opened, a hose bursts or the pump splits open. The relief on the Travel spool should be the one that will open just as soon as the pressure reaches 1850 PSI and it will be wide open at 1900 PSI. If the volume of oil produced by the pump cannot be handled 100% by that relief and the pressure rises to 1950 PSI, then the relief in the PTO will crack open.

In a different scenario, let's say that the Travel relief is set at 1900 PSI but the spring in the PTO relief is damaged slightly and even though the factory set it to open at 2100 PSI, it now opens at 1400 PSI. The tractor begins pushing dirt once more and is stopped in its tracks, thus causing the drive motor to stop while asking for more pressure. The motor would have come to a halt at 1400 PSI because the PTO relief would have opened at that pressure even though there was no attachment being powered by the PTO. In other words, the PTO's relief valve is in play 100% of the time. That relief does not just protect the pump from high pressure created by attachments connected to the PTO...... it also protects the pump from ANY problem that happens downstream from it. Let's say that an owner cranked the relief in his travel spool down to the point where it would not open at all. The PTO relief would then be the only protection for the pump if the drive motor stalled out.

Getting back to Rob's situation, it is highly doubtful that the OEM PTO on his tractor will have a relief valve that could have been adjusted by someone with a screwdriver or wrench. Therefore it is unlikely that anyone messed around with the relief setting. We also seem to have a disagreement as to what the factory relief settings are supposed to be thanks to what Rob sees in his Service Manual and what I see in the Hydraulics Manual which was written years later. The fact that this tractor never got an oil change in 40 years implies that the pump is pretty worn. And if they were removing the tiller and putting it back on again when needed, then there were plenty of opportunities for contamination to happen when the hydraulic lines were disconnected. To me, this is a tough one to resolve when you don't have all the needed test equipment at hand. The pump needs to be put on a flow bench to see how much pressure it will truly put out along with the GPM at that pressure. The PTO valve should also be removed and put on a test bench where the true blow off point of the relief can be ascertained.

The only other option would be to install another pump that is KNOWN to be 100% and see what the results are at the gauge. If the highest pressure obtainable with the other pump is still 1075, then you know that the pump was not the issue and that the relief valve in the PTO is highly suspect. Then again, I suppose that you could remove the PTO from the list of suspects by disconnecting the two hoses that are attached to the IN and OUT ports and joining them directly to one another but with the Tee and gauge still in place. Run the dozer test again and see how much pressure you get. If 1075 is the max, then a new pump should solve the problem. If the pressure reaches 1450 or better, then the relief springs in the PTO valve are either broken or weak.

Those are my thoughts at 6 AM on a Friday. :lol: :lol:

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Rockdog

· #12 · Jan 6, 2012

Brian I agree - the PTO wouldnt cause the low pressure at TCV (well, there IS a pressure drop accross it directionally proportional to flow but probalby not and issue here). i guess the point I was trying to make is that if the drive motor is shot and the TCV relief leaks then it is very possible there wont be much pressure with a worn pump. So could be a pump and motor issue. If one can still get both of these easily and cheaply then great. If not then maybe its best to keep this sentimentally valuable machine as-is and get something else to do the hard work.

Hydriv - "any relief valve that is upstream of a motor or cylinder will limit the pressure in the system to the extent of the relief setting." This would be true if the relief drained to tank. In this case the PTO valve is in series with the TCV so the actual relief crack pressure is equal to its 'set' value PLUS the pressure ahead of the TCV. In your first scenario below the PTO relief wouldnt open at all because there would be essentially no pressure differential accross the PTO relief valve. In the second scenario the pressure drop accross the PTO valve is essentially zero and the PTO relief would not open. So, in other words, as Brian stated, the PTO relief only comes into play when the PTO is engaged and because it is in series with the TCV the relief is not necessarily protecting the pump (depends on downstream pressure).

Now if there is a Flow Control Valve in the picture with flow being diverted to tank then the PTO relief certainly may work as you described if the PTO is engaged. But the amount of flow being split off will determine affect the pressures at the TCV and PTO valve.

Hopefull the flow control valve on this machine is in good condition and during the 'dozer' stall tests it is directing all the flow to the TCV....

If good pressure if found by plugging flow control valve return to tank port than the pumps good. Can check the motor by plugging work port of TCV as well - which would also check its relief.

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Hydriv

· #13 · Jan 6, 2012

Rockdog wrote:

Brian I agree - the PTO wouldnt cause the low pressure at TCV (well, there IS a pressure drop accross it directionally proportional to flow but probalby not and issue here).

Upon reading this post, I would also have to agree. See below.

i guess the point I was trying to make is that if the drive motor is shot and the TCV relief leaks then it is very possible there wont be much pressure with a worn pump. So could be a pump and motor issue. If one can still get both of these easily and cheaply then great. If not then maybe its best to keep this sentimentally valuable machine as-is and get something else to do the hard work.

On that point......I totally agree. I have said repeatedly that the old 100 Series tractors are now beyond their "Best Before" date as work horses and should be retired. Bring them out as a nostalgia piece for shows and parades. However, that is just my opinion and the tractor in question does not belong to me. Therefore, Rob is entitled to try and make use of it.

Moving now to costs. A new Type A pump will cost him around $250.00 or so. A new drive motor will likely cost a max of $400.00 but I have not priced these lately. If he is capable of rebuilding both valves (new relief springs plus shims) then I would think that $100.00 max would be the budget figure. That totals $750.00 to restore the hydraulic system to near original condition but does not include another round of fresh, clean oil nor the time and materials needed to remove any linkage slop. In the end, you now have a tractor with a frame and axles that are weaker than the ones found on any 1973 to 1988 Case 444, 446 or 448. Plus, there is no factory 3 point available plus you don't have the advantage of the Snap Fast system and all of the easily found attachments that use that system. In other words, all those pluses are actually minuses in my eyes. As it stands right now, Rob could just ignore all those issues and instead.......strip this tractor to the frame, repair the problems he finds with mostly his own labour and some low cost parts, repaint the entire tractor, add new decals while re-assembling it and end up with a nice show tractor. The existing engine and hydraulics all work well enough to parade the tractor and to drive it on and off a trailer. Paint and decals ---$75.00. Maybe $200.00 for some miscellaneous parts and you have a show tractor you can be proud of.

Finding a low cost 444 with a decent engine would be the next move and then do what's necessary to make that the work horse.

Hydriv - "any relief valve that is upstream of a motor or cylinder will limit the pressure in the system to the extent of the relief setting." This would be true if the relief drained to tank. In this case the PTO valve is in series with the TCV so the actual relief crack pressure is equal to its 'set' value PLUS the pressure ahead of the TCV. In your first scenario below the PTO relief wouldnt open at all because there would be essentially no pressure differential accross the PTO relief valve. In the second scenario the pressure drop accross the PTO valve is essentially zero and the PTO relief would not open. So, in other words, as Brian stated, the PTO relief only comes into play when the PTO is engaged and because it is in series with the TCV the relief is not necessarily protecting the pump (depends on downstream pressure).

Now if there is a Flow Control Valve in the picture with flow being diverted to tank then the PTO relief certainly may work as you described if the PTO is engaged. But the amount of flow being split off will determine affect the pressures at the TCV and PTO valve.

Yes.... upon reading your post, I must agree. When the relief in the PTO opens due to the tiller stalling, the high pressure fluid is diverted to the low pressure side of the valve so that it can return to the reservoir easily. However, if the motor stalls, then there is no such thing as a low pressure side for the PTO's relief to dump into. Therefore, no pump protection is afforded. Good point, RD. :thumbsup:

Hopefully the flow control valve on this machine is in good condition and during the 'dozer' stall tests it is directing all the flow to the TCV....

If good pressure is found by plugging the flow control valve return to tank port then the pump is good. Can check the motor by plugging work port of TCV as well - which would also check its relief.

Yes. That is a good test for Rob to try and it's cheap as well as being easy. Remove both lines that go from the TCV to the drive motor and install plugs or caps on the work ports of the TCV. Start the tractor and push the Travel lever forward and note the max pressure on the gauge. And while you are at it, pull the Travel lever backward and note the max pressure on the gauge. May as well see if there is any difference in the readings. :lol:

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case680rob

Discussion Starter · #14 · Jan 7, 2012

PTO valve and FCV, before installing the gauge. Gauge was mounted between the high pressure line on the right and the last fitting connected to the high side of the PTO valve.

Alright guys, I know my 190 is an antique, and a family heirloom at that. I also know that pushing the pressures up will put more stress on the whole machine. I agree it should be retired and is in good enough condition to be spruced up and put away for parades and the occasional mowing. Can't do that yet guys, it's the ONLY tractor I have, and unemployment doesn't buy tractors. As far as buying a newer model goes, I can get a decent 8N Ford or better for the price that CCI units go for out here. Just ain't in the cards right now.

Some additional valving info.

The squeal of the PTO valve only happens when the tiller is in use. Also, the PTO valve is in series with the rest of the system, as previously stated. The valve has four ports: two work ports, a high pressure port, and return or low pressure port.

The FCV is connected to the return port of the PTO valve. There are high pressure, regulated, and bypass ports here, and are marked as such with cast letters at each port. Also, there are two allen head screws which may have releifs behind them. One of these screws is seen in the picture above.

Bottom line is I don't have another pump or acces to one, and at my current finanicial state $200+ would go a long way to getting a larger tractor.

First chance I get I'll try the pump test, TCV test, FCV test, and any other quick cheap test I can do. Any other thoughts? I'm all ears.

Rob

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Rockdog

· #15 · Jan 7, 2012

I hear ya regarding it being your only tractor. I'm of the mindframe that these are only tools to be used (mines a turd though). But if I had one that had been in the family like yours I'd feel differently about that particular one - especially as yours appears to be pretty nice. The first Case I was going to buy was a 155 or something but after reading here and elsewhere that parts for those were much harder to come by I passed. So I can understand that at this point you really cant replace major components right now no matter what the outcome of your 'tests'. Just be keep your eye on the gage and be ready with the valve handles in case it ramps the pressure up.

case680rob

Discussion Starter · #16 · Jan 7, 2012

New information.

Today I successfully adjusted the pressure of the releif valve at the PTO control. By removing the allen-head plug seen next to the base of the control lever ( seen above in the pic I posted earlier ) I found the spring and adjustment shim/washer. The washer, where in contact with the spring, was worn a bit, indicating that the spring moves alot. I reinstalled the spring and washer, this time with another washer of very similar size. With the two washers installed I conducted another "test". This time I only ran the tiller test, knowing that the releif I adjusted is protecting the pump ONLY when the PTO is in use.

When the tiller test was first done, I was able to easily "stall" the tiller by having the tiller in "forward" and reversing the tractor and forcing the tiller to go deeper into the soil. As the stall occured I would hear the releif valve pop with it's "squeal" and immediately shift the tractor to forward to reduce stress on the system.

After adjusting the releif valve, I performed the test in the same way, over the same patch of ground. At no time was I able to stall the tiller, nor did I hear the releif valve pop. On the gauge, under heavy load of the tiller buried in the dirt, readings averaged just over 1000psi and for a few seconds would jump up above 1200 while clearing a rock. I watched this happen several times. It seems as if the releif valve adjustment at the PTO control valve was a success.

Rob

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gator_rider2

· #17 · Jan 8, 2012

Keep shimming up to above 1350 psi remember rise may stop because the relief in TLC need to be shimmed.

Hydriv

· #18 · Jan 8, 2012

I don't know why you were not able to stall the tiller. Albeit that you have an early model (E-1600) but I could stall my J-Series tiller, no problem and it was mounted on a fairly new 446. The PTO on my tractor was set at 2200 PSI.

You still have to figure out what's going on in the travel circuit. After all, 1200 PSI isn't exactly stellar performance for your pump.

case680rob

Discussion Starter · #19 · Jan 8, 2012

I'll try backing the tiller into a hill to stall it. I didn't aim for any big rocks or roots as the higher pressure is more than what this tractor has seen since probably 20+ years ago. I'll keep shimming until it is right. After I get the PTO set I'll see about the FCV and then the TCV. One step at a time here.

Rob

gator_rider2

· #20 · Jan 8, 2012

Rob good post you going in right direction with pressure and there be like new performance in Tractor. Because Engine horsepower your book is an has right information on psi setting. This repair cost you price of shims smiles.

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