Another 450 clutch question

[Georgia088]

I know y’all are going to think I’m crazy, but I have another question about a 450 and doesn’t relate to my other threads.

I have a “parts” crawler jd450 straight. It has been sitting for over a year with a bad clutch. It is actually in better shape than the one I’ve been workin on. So, I decided to try and fix it.

I took engine out and sure enough the clutch was frozen to flywheel, but it was completely broken from the spline. So, I replaced it.

Got it back together and I’m at my first problem. I am trying to make the adjustment On the clutch pedal as the manual states, but I can’t get the 3-3/4” of free play with the pedal before adjusting the 1/2” jam nut in the bell housing.

I don’t understand why. If I tightrn the 3/4 bolt on the pedal it bottoms out and the end of the bolt contacts the Clevis type linkage. If I loosen the bolt, it simply becomes loose. And there is a gap between the head of the bolt and the pedal stop, but the free play remains the same. About 1” of free play before you can feel the throw out bearing contact the pressure plate. I need to increase the free play quite a bit.

Is it possible the 1/2” jam nut adjustment inside bell housing is so bad out of adjustment that it could prevent the free play adjustment from reaching the 3-3/4” as the manual states?

Which way should I be turning the 3/4” bolt to add free play to the pedal and make the stroke of the HLR longer before the throw out bearing presses against the pressure plate, clockwise or counterclockwise?

I am fairly certain the adjustment of the HLR is causing problems. The machine will move but with little to no power. If I slightly press the clutch down it pulls harder with more power. This seems to me the hydraulic pressure is increasing but if I continue to press the pedal, the clutch decouples the motor from the transmission and removes all power.

Any help as usual is appreciated!

Thanks!

 

[Jim.ME]

Did you check and adjust the engine clutch pressure plate finger height if required? With the JD227 gauge or other method? If other how and what did you set them to?

When you had the engine out did you check that all the return springs were in place inside the clutch housing and that all the linkage moved freely?

The 450B manual says loosen the bolt to increase travel (free play) and tighten to decrease travel (free play). I am going to say that if the clutch valve screw has been adjusted with the pedal free play incorrectly set, you may need to back it off out of the way to adjust the pedal free play, then adjust the clutch valve, just as if every part was a new install.

Edited to correct punctuation.

 

[Georgia088]

Did you check and adjust the engine clutch pressure plate finger height if required? With the JD227 gauge or other method? If other how and what did you set them to?

When you had the engine out did you check that all the return springs were in place inside the clutch housing and that all the linkage moved freely?

The 450B manual says loosen the bolt to increase travel (free play) and tighten to decrease travel (free play). I am going to say that if the clutch valve screw has been adjusted with the pedal free play incorrectly set, you may need to back it off out of the way to adjust the pedal free play, then adjust the clutch valve, just as if every part was a new install.

Edited to correct punctuation.

This is my second clutch install in about a month on two different tractors. Because I am impatient, I did not adjust the finger plate height on this one. I did on the first one because it was sticking and needed some love freeing it up. However, most people on the forum agreed they shouldn't need adjusting and just install or replace. I inspected this pressure plate and it appeared free and worked without issue. So, I just reinstalled with new clutch.

However, I am convinced this may be my issue. Perhaps the finger height is larger than they should be forcing the throwout bearing to contact it earlier than it should. The reason is I have done everything I can think of even removing the lock bolt where the clutch pedal attaches to the shaft. I tried adjusting this so that I would have some adjustment with the 3/4" bolt, but it didn't help. I also removed the nuts and the top "stop nut" from the HLR adjustment screw that is in the bell housing. I inspected and moved the lever in the bell housing that controls the hydraulic valve in the transmission. All seems good.

I have put it back together and made a (not sure of the word) "crude" adjustment that seems to be working. I backed the crawler up to a large dirt pile in reverse. It stalled because the HLR was not adjusted correctly. While still in Reverse and the clutch pedal out I began to turn the 1/2" HLR adjustment screw until it started pulling strong up the hill. You could feel the power through the tracks increase drastically until I turned the nut too far. I backed it back out and got to where I was getting the maximum "feel" of power to the tracks.

It is pulling very strong and spinning the tracks or choking the engine down in first and second gear now. I haven't tried 3rd and 4th as I rarely use these. I plan to check the pressure as described in the manual, but I don't think I am going to pull the engine again to see why I can't get the 3-3/4" free play. The engine clutch is obviously working as I can shift from 1-4 without grinding if clutch is depressed. If I press the clutch in about 1-2" (the amount of free play I have) It stops the tractor and seems to be controlling the HLR like it should.

I know this is not ideal, but I don't know what else to do other than pull the engine. I don't really want to tackle that again right now.

Thanks for the help and I am still open to any ideas!

 

[Jim.ME]

I have encountered enough new pressure plates with uneven or out of adjustment fingers that I am going to take the few minutes to check them as directed in the service manuals. And I wouldn't do the work of pulling an engine or splitting a unit and not replacing a single disc pressure plate or overhauling a dual stage one.

Personal choice, each to their own. Glad you got it going, I hope it continues to work for you.

 

[Georgia088]

I have encountered enough new pressure plates with uneven or out of adjustment fingers that I am going to take the few minutes to check them as directed in the service manuals. And I wouldn't do the work of pulling an engine or splitting a unit and not replacing a single disc pressure plate or overhauling a dual stage one.

Personal choice, each to their own. Glad you got it going, I hope it continues to work for you.

Agreed. I won't do it again..... Thanks!

 

[crawlercollecter]

I know y’all are going to think I’m crazy, but I have another question about a 450 and doesn’t relate to my other threads.

I have a “parts” crawler jd450 straight. It has been sitting for over a year with a bad clutch. It is actually in better shape than the one I’ve been workin on. So, I decided to try and fix it.

I took engine out and sure enough the clutch was frozen to flywheel, but it was completely broken from the spline. So, I replaced it.

Got it back together and I’m at my first problem. I am trying to make the adjustment On the clutch pedal as the manual states, but I can’t get the 3-3/4” of free play with the pedal before adjusting the 1/2” jam nut in the bell housing.

I don’t understand why. If I tightrn the 3/4 bolt on the pedal it bottoms out and the end of the bolt contacts the Clevis type linkage. If I loosen the bolt, it simply becomes loose. And there is a gap between the head of the bolt and the pedal stop, but the free play remains the same. About 1” of free play before you can feel the throw out bearing contact the pressure plate. I need to increase the free play quite a bit.

Is it possible the 1/2” jam nut adjustment inside bell housing is so bad out of adjustment that it could prevent the free play adjustment from reaching the 3-3/4” as the manual states?

Which way should I be turning the 3/4” bolt to add free play to the pedal and make the stroke of the HLR longer before the throw out bearing presses against the pressure plate, clockwise or counterclockwise?

I am fairly certain the adjustment of the HLR is causing problems. The machine will move but with little to no power. If I slightly press the clutch down it pulls harder with more power. This seems to me the hydraulic pressure is increasing but if I continue to press the pedal, the clutch decouples the motor from the transmission and removes all power.

Any help as usual is appreciated!

Thanks!

I have in the past cut of the end of that bolt and thread it a little deeper when i ran in to that problem, seemed to work okay by doing that.