JD straight 350 steering clutch won"t release

[cwheat]

Hello all,
I have a 350 with a straight transmission/power steering that the right steering clutch will not release. The clutches are pulling good and will spin both tracks if you try to push something that won't move. I have removed the cover and the linkage is working on top but I can not see any movement down around the pressure plate. Checking the clutch settings according to the book will cause the ball adjuster to run out of threads and screw off the adjuster threads before it reaches the point the socket will line up with the ball. Dozer sat up for about 5 months before I bought it last month. Left clutch and brake is working perfect, just the right one acting up. The right brake will bog the engine when you pull the right steering lever so the clutch just is not releasing and there is not enough throw on the linkage for it to work the clutch fingers. Wondering if some of the members have any words of wisdom. It acts like the pressure plate has broken all the springs, throw out bearing or carrier has failed or the yoke pins have came out or could it possibly be the discs swelled up bad enough to compress the springs on the pressure plate so the throw out bearing can not reach the fingers to disengage it? That does not seem likely to me as there was no oil or moisture in either clutch cavity so swelling because of moisture should not affect one side and not the other. Has any one got any ideas? I have completely ran out of my own other than to break the track and disassemble the final drive which I was hoping to avoid.
Thanks,
Charles

[cwheat]

also wanted to add that the machine was having fuel delivery problems that the prior owner thought was a defective injector pump. He did not want to spend the money to repair or replace the obsolete model c fuel pump, hence the reason he sold it to me. In the end the pump problem was solved with a hundred dollar after market solenoid valve that cut the flow to shut the engine down. All this to say he told me both clutches were working perfect before the fuel problem started about 6 months ago so if that is true the right clutch may have quit working because of accumulated moisture from not being used. Does that make sense???

[LeonardL]

Your issue is most likely rusted or seized linkage related. If the linkage seizes to the pivot shaft then it will cause the adjuster to not have enough threads to extend out before it comes off. It will also cause the brake to engage before the clutch can release.

You need to make sure everything is working freely and independently from the other inside the clutch housing. When you first pull the lever, the only pieces moving should be the clutch linkage. It has to pivot on the horizontal shaft that it pivots on. At this time it should also be moving the throw out bearing towards the fingers on the pressure plate.

If the linkage is trying to move more than this, as in forcing the brake actuator lever to move with the clutch linkage then it can't release the clutch first.

Back the little brake adjusting screw off so that it can't apply the brake band and see if the clutch lever is moving freely. This is the small brake screw not the big brake band adjusting bolt. Back it out all the way until it is flush with the brake actuating lever. Work your steering lever and see what it is doing. If the brake lever tries to move in unison with the clutch lever then it is seized. If it is all stuck together then at this point you want to get your penetrating oil out and try to get it freed up.

I doubt that it is a swollen disc issue. I've never seen that happen and it would take a lot of water to ever cause that to begin with. If they're wet then they slip. I've never seen them swell.

If your linkage is okay then look down at the throwout bearing to see if the set screw has loosened on the throw out bearing fork. If that is the case then you will have to pull the final drive to access it.

I really think you have a seized linkage however.

[original possum]

Saw one like this once where they had assembled the clutch wrong. They didn't realize one fiber goes inside the snap ring.

[cwheat]

I did as you said and loosened the little brake pivot adjuster all the way off and that still did not give me enough adjustment to extend the clutch ball adjuster enough before it unscrewed from the male threads. So the brake adjusted too tight was not what was causing the problem. I can see the vertical shaft moving on the top but can not see deep enough in the cavity to tell what is happening at the throwout bearing and fork assembly. I have got a little inspection mirror ordered that may let me get it by all the linkage enough to see what is happening but I don't have much faith in that. It looks like I will have to pull the final drive to fix it. May be the throw out bearing fork set screw loose like you said or maybe just disks worn out but the machine pulling hard with absolutely no clutch slippage sort of makes me think the clutches are not worn that bad. Who knows until it is torn down and the problem identified for sure. Thanks for the support. Charles

[LeonardL]

Okay so unfortunately you have totally misunderstood what I was trying to get across. That is on me for not explaining it better. I wasn't intending for you to gain any more adjustment at the clutch adjuster. What I was trying to get across is the brake actuator lever is stuck or seized to the horizontal shaft. When this happens it applies the brake before the clutch and that will bog the engine and not release the clutch. It has to be clutch first and brake second. If the brake actuator lever is seized to the shaft it applies the brake first and the clutch doesn't disengage. This also causes you to think the adjuster doesn't have enough threads to compensate. You run out of adjustment long before you gain anything.

The brake actuator lever should pivot freely and independently of the clutch actuator lever that is fastened to that same shaft. By backing that brake adjuster screw off, it allows you to work the steering lever to see if both actuating levers on that horizontal shaft move at the same time. When you pull the steering lever the only thing that should move in the first few inches of steering lever travel is that clutch actuating lever. If both of the actuating levers move together in that first few inches of steering lever travel, then they are seized together on that horizontal shaft. Follow me? We're not talking about making any adjustments at this point. We are trying to get the linkage working properly or at least verifying that they are working properly.

This is a process of elimination of the factors that can cause your issue. If the linkage is working as it should then you need to look at the next step and that is to ascertain if everything is assembled correctly and located in their proper positions. That being the clutch actuator lever on the horizontal shaft could have sheared its key and slipped out of position. If that is okay you move on to the throwout bearing mechanism. That consists of a vertical shaft that leads from the top of the steering clutch housing to the bottom. It has a lever attached at the top with a set screw that pivots that shaft which then rotates the throw out bearing fork. The lever at the top could have turned out of position by being loose on the shaft or the fork itself can get loose and has turned on the shaft.

So, what I'm saying is you need to establish what is working properly and what is not. If everything ahead of the clutch is correct and working properly then you move on to the clutch itself. You need to ascertain that all the mechanism is working as it should before you go to all the trouble of removing the final drive and tearing into the clutch.

I really doubt that you have a clutch issue. I'm not saying it isn't possible because anything on this old iron is. These 350s have made a fool out of me more than once. All I'm saying is I have never had a clutch pack itself be the issue you describe. I have had them rust solid and not release and I have had them get soaked with water and they will slip. It could be a seized pressure plate or one that is out of adjustment. What I am saying is usually there are factors way ahead of the clutch that cause what you say is happening.

[cwheat]

I do think I understand what you were saying. I probably did not use the right terminology in saying that it did not give me more adjustment on the clutch actuator. After I backed the small brake adjuster off to be sure the brake was not engaging first and preventing the clutch actuator from working I did determine that the arm on the horizontal shaft that has the adjustment bolt in it was in fact moving with the shaft and linkage when I pulled the steering lever back. Also the arm that the small brake adjusting bolt pushes against to move the brake linkage is moving independently(not seized to the shaft) from the horizontal shaft. There was still not enough threads on the clutch adjusting knuckle to extend far enough to reach the ball due to whatever is the problem. I did loosen the set screw and jam nut on the vertical shaft clutch actuator lever but it did not appear to be loose and have moved in relation to the indention on the shaft but I did not try very hard to move it on the shaft. I did try to use my new inspection mirror to be able to see the throw out bearing actuating collar on the bottom of the vertical shaft to see if it appeared the set screw was loose an allowing it to move on the shaft but there is must too many shafts, levers, and piping in the way for me to see it. I guess I am still thinking the final drive has to come off to be able to find the problem. I hope I am understanding your instructions correctly and conveying back to you what I see accurately. What I have not done but plan to is to remove the left inspection cover and compare the left to the right side as in the relation of the vertical shaft actuators and ball joints to the final drive casting. I expect to see the clutch actuator ball joint on top of the vertical shaft a little more toward the rear of the tractor on the one that is not working right compared to the one that is working right, hence the reason the adjuster is running out of threads before extending enough to let the joint drop onto the ball when holding the lever against the clutch fingers like the adjustment procedure dictates. In fact when I hold the lever toward the clutch fingers with a bar and feel it when it when the throw out bearing touches the fingers at that point the lever is very close to the casting of the clutch cavity and there is very little to no room for more movement even if slop in the linkage was the culprit. It appears to me that the problem has to be in the vertical shaft or some of its components like maybe one of the set screws on the lever or throw out bearing collar actuator has loosened and let that setting have excessive slop or one of the two bolts that move the throw out bearing maybe has screwed out and is failing to move the clutch fingers enough to disengage the clutch. I appreciate the guidance and your thoughts. I have spent the last 60 years working in maintenance of heavy equipment and have been known to develop tunnel vision at times so if this is one of those times please bear with me and don't give up. Thanks again for your support. Charles

[LeonardL]

Hey... I just had another thought on this. You say the machine has power steering? Check the adjustment on the steering cylinder clevises for that side. I have had them be off and it affects the throw on the levers inside the clutch housing.

[cwheat]

I don't remember seeing anything in the manual about how to adjust the power steering clevis. Should I make it longer or shorter? Longer would be my first thought. I do remember reading that the free travel should be up to an inch more for one that has power steering.

[cwheat]

I had a few more thoughts after you mentioned the power steering. When I first got the machine the power steering reservoir was empty and had a leak in one of the lines that I did not know about at that time because I did not even know it had steering assist. The left was working then and the right was not but I could muscle the steering levers back and the left would turn and the right would not. After I got it running and was trying it to see if everything was working I realized it had the steering assist and found the reservoir empty and filled it with oil. The steering levers immediately got several times easier to pull back on both levers but the right steering was not any better. I then fixed the leaking line I found and stopped the reservoir from emptying but all that did nothing for the right steering that was not working in the first place. I assume these helper cylinders work like some of the earliest power assist steering on wheel tractors in that the cylinder has a valve arrangement that helps move the cylinder(and steering arms, wheels, ect.) but still has a solid connection that will steer the tractor with brute strength if the hydraulic did not work. Am I correct in that assumption? If so I am going to remove the floor plates and anything that is covering the steering linkage and compare each pin and pivot joints movement of each side with the other and determine if both are the same. In other words If the helper cylinders are a hard connection that will work with or without hydraulic pressure and the linkages are more or less moving the same amount when comparing one side to the other there is still something wrong downstream of the linkage, and if there is difference in the two sides of linkage movement I will adjust that out and see if it changes the outcome. Am I thinking right or wrong here? If the cylinders theory of operation is such that the cylinder had to be working properly before the linkage behind the cylinder would move the right cylinder may not be working like it should but since both sides got easier to pull back when I initially filled the reservist makes me think it is just a helper cylinder and really has a hard connection to the linkage and it does not matter if the power assist is working for the clutches to operate other than being harder to pull the levers. I don't guess there is a bleeding sequence of some sort that has to be done to the helper cylinders to make them work is there? I do not remember reading in the manuals that had to be done. So much I do not know about this tractor!

[LeonardL]

So it has been forever since I last worked on the power assist cylinders on these machines. So I don't remember a lot about them. However that being said, you are correct in your assumptions in how and or what they do.

The valving action is all done inside the cylinders. They activate internally as the cylinder pivots on linkages that the cylinders are mounted with to the machine. I figure the guy who designed these at Deere back in the day was either on drugs or needed to be on drugs. LOL!!

I do remember them not working correctly if the bushings in the sides of the cylinders and the pivots get worn badly. They will pitch out to one side and not let the cylinder function properly. They are as you say still a hard connection to the steering mechanism that works everything inside the steering clutch housing.

What I have seen happen is people will get an issue with the steering and they try to compensate by adjusting those clevises. Which messes the hard connection up. Usually the culprit in their issue is actually the pivots and not the overall length of the cylinders connection. As a result the throw on the lever that enters the steering clutch is off and causes the adjustments of the inside mechanism to be wrong as well.

And no, there is no bleeding sequence on the hydraulics as it is a flow through system. The fluid is pumped through the cylinders and then returns to the reservoir. So as long as you have fluid and no leaks then the system is constantly pressurized.

[cwheat]

The more you talk about the system the more sense it is making. We have a few more days of this unpredictable southwest Mississippi weather to deal with but when it lets up I am going to do the comparison of the right and left linkages and their movements. I have gotten to old(85) to work in the cold and dampness and if it was not for getting it running for my grandson I would probably not even started the project. Several weeks ago it was to hot and humid, Now it is too damp and cold. The weather may never cooperate so I can fix it, but if and when it does I hope I can find something simple like those worn bushings binding it or someones prior adjustments causing it. Thanks so much for letting me rant and rave with the lengthy postings.

[Tonybain42]

Hello all. I was just wondering if you ever figured out why your clutch was not releasing. I recently got a 1970 JD350 and I'm having the same issue on the left side. I have looked under the seat through the access panel. I can see it all moving but the left clutch seems to be farther out than the right side that works perfectly. When I attempt to turn left lots of lever pressure, but no turning at all. The right lever has considerably less force to turn as it should.

[Jim B]

Welcome to the boards.

If you put the blade, or bucket, against something solid and try pushing in low, do both tracks spin? Are the steering clutch compartments clean and dry?

Do you have an Operator's and/or Service manual for it? Have you tried adjusting the steering system by the book?