nortrac dozer trouble

[20 20]

Basically my dozer won't stop moving, it was acting odd and became worse. I push the clutch in, idle down and it still keeps going. My question is will I have to split the machine to find out what is wrong, I've allready ajusted the clutch lever? Is there away to get inside the clutch housing without basically stripping the machine down? Thanks for any ideas.

 

[20 20]

I may have figured something out, I forgot about the pin in the clutch arm/lever connecting it to the release fork shaft. If these are anything like the tractors I know these pins aren't worth a dang {we need a smily for crossed fingers}.

 

[teg]

I assume that you can you turn the machine... so the steering clutches are fine???

 

[20 20]

Yep it turns and runs fine just can't get it out of gear or in {unless I shut it off or grind the__ out of it{no I won't do that}}. I push in the clutch and it acts like it is partially disengaging it would even stop when pushing into something{clutch pressed}. This did become worse and eventually even with the clutch pressed in it wouldn't make a difference. I just tried to check the shaft, lever, and pin but it's getting dark and hard to see. I'm wondering if it slipped lever on shaft{pin broke} if it still may rotate the shaft but not enough to engage. It's hard to see up under the floor board looks like I may have to remove it to get in there?

 

[Bob Rooks]

Do you still have free travel in the clutch pedal? About 3/4"?
Hear any strange noises when clutch pedal is depressed?

 

[20 20]

There is free travel, it does sound like it's trying to disengage, no clunking or banging noise, hard to explain.

 

[Bob Rooks]

There is free travel.

How much? This is important.

An oily or greasy clutch disc will have those symptoms, but not to the point of stalling the engine.

 

[Gene :^)]

Definitely check that pin that holds the clutch arm to the pivot shaft. I replaced mine with a bolt and tack weld, then never had to touch it again. However, a new pin might be sufficient.

Gene :^)

 

[Bob Rooks]

Let's keep the weak link on the outside of the clutch housing. It's far more convienient on a dozer to replace a pin on the outside than to remove the engine, or in the case of a wheeled tractor, to split it. You can always double up on the pin or install a coil pin. It's your call though.

 

[20 20]

Thanks for all the ideas folks I'll add to my OP maybe that'll help explain it better.

I started the dozer to move some snow banks back, let it warm up for 10min or so. Jumped on and started out slow like allways {1200rpm} moving around just getting things warmed up. Once I ran/drove it for a few min. I brought the rpms up to 1600rpm and begain my work, everything was going strong. Had no issue's, dogging or over working, actually snow is kind of like plowing puffy clouds, IMO real easy work for this dozer. I plowed for a good hr and noticed it started to grind a little when shifting back and forth into gear. At 1st I figured maybe my foot was getting lazy{operator error} so I started paying close attetion and making sure the clutch was depressed all the way. From there things got worse it slowly and steadily got to where I had to shut it of to put it in gear to limp back to the shed.

Basically it acts like direct drive, the clutch depressed will stop it if it is pushing on a some what inmovable object{snow pile etc.}

Bob Rooks; I would say it had .75 to an 1" of play. It never did stall the engine just acted like the clutch would not disengage all the way. I hope the above helps explain what is going on better.

Gene :^) ; I was wondering the same thing, my jinma tractor had the same issue as yours I replaced the pin{double if I remember correct} and it never had another issue. I do agree with Bob Rooks though I don't think I'd weld that arm, easier to keep an issue out side then cause internal problems. I'd much rather just replace a pin every now and then compared to tearing down the machine.


Thanks again for the opinons/advice/help folks every little bit gets me pointed in the right direction IMO :thumbsup: :drink:

 

[20 20]

Another update, I pulled the floor boards off and checked the pin, nothing wrong, i was hoping this would be it :mur: I pulled the plate{clutch housing} to see what is happening, everything seems to moving the way it should. While I had the plate off I did notice muddy water traped inside . There is a small weep hole in the bottom that had gotten pluged. I fished out the weep hole and drain the nasty water, not a huge amount but am thinking this may be my problem.

I Put everything back together made adjustments and tried it, depressing the clutch while it was up against a tree did disengage for a short time{20-30seconds}. I did this a few times each time same result, it would disengage for a short time then would start too bog down{so I'd kill the engine}. Could the water have been enough to mess up the clutch plates? I'm quessing there is no easy fix, is pulling the engine the easiest way to get at the clutch?

If I have to pull the engine it will have to wait until april or may seeing I'll have to do it in the drive. Thanks again for any ideas

 

[Diamondpilot]

At this point it seem to me you have nothing to loose so I would wash down the clutch with many cans of brake/parts cleaner. Then check the adjustments. I would then work it some and see if it does not work itself clean and work properly. If not you are not out much.

Chris

 

[Bob Rooks]

Another update, I pulled the floor boards off and checked the pin, nothing wrong, i was hoping this would be it :mur: I pulled the plate{clutch housing} to see what is happening, everything seems to moving the way it should. While I had the plate off I did notice muddy water traped inside . There is a small weep hole in the bottom that had gotten pluged. I fished out the weep hole and drain the nasty water, not a huge amount but am thinking this may be my problem.
It's doubtful that water could have caused swelling of the friction discs. I would try Chris' suggestion in case there is oil or grease on the discs. Wouldn't hurt anything.

I Put everything back together made adjustments and tried it, depressing the clutch while it was up against a tree did disengage for a short time{20-30seconds}. I did this a few times each time same result, it would disengage for a short time then would start too bog down{so I'd kill the engine}. Could the water have been enough to mess up the clutch plates?
Try adjusting more free play out of the pedal, say take it down to 1/2" - 3/8" and check performance. If that helps then there is issues with the presure plate, possibly bent or broken fingers or even clutch release bearing problems.

I'm quessing there is no easy fix, Nope.

is pulling the engine the easiest way to get at the clutch?
Nope, it is the ONLY practical way. Sorry.

12345

 

[Gene :^)]

Water, mud, oil, and grease all make a clutch slip. Meaning not able to go or maybe just not able to push things due to slipping.

You have the opposite problem, not able to disengage or grabbing. Meaning the clutch disk surface is fine.

You said after adjusting it seem to work for a short time and then started to grab again: This is most likely because it was not completely disengaged and was dragging causing heat from friction which expanded everything and made it tight again(engaged).

1st: You need to really make sure that pin is good, it might look good at the ends but the center can be crushed or sheared.

2nd: You need to reduce free play close to zero and see if it disengages, then add freeplay until you find the sweet spot.

Note: I don't understand the need for a "weak link" in the clutch release mechanism. The only forced applied is from the driver's foot. If something is jammed you would feel it, and unless you are a Gorilla you wouldn't keep pushing until something broke inside.... would you? I didn't weld the entire thing, I just put a 3/8 inch tack on the edge of the shaft to the edge of the clutch pedal arm. If I ever need to, it would take about 30 seconds to grind it off. The tack just prevents any slop in the pin because even a tiny bit of slop in that pin can throw the clutch WAY out of adjustment.

Gene :^)

 

[ultrarunner]

Working on old Fordson tractors I've had two clutch issues where it wouldn't release.

On one it was the clutch plate the disintegrated to the point it overlapped and was actually double thickness... the pedal had lots of free play and I had to replace the disk.

Another time, it was a bad throwout bearing.

 

[20 20]

Water, mud, oil, and grease all make a clutch slip. Meaning not able to go or maybe just not able to push things due to slipping.

You have the opposite problem, not able to disengage or grabbing. Meaning the clutch disk surface is fine.

You said after adjusting it seem to work for a short time and then started to grab again: This is most likely because it was not completely disengaged and was dragging causing heat from friction which expanded everything and made it tight again(engaged).

1st: You need to really make sure that pin is good, it might look good at the ends but the center can be crushed or sheared.

I can check again but I did check it and even tried to force it to move either way for slop. I also tapped it{pin} out part way and nothing binded, could see straight through the center of the pin no bends.

2nd: You need to reduce free play close to zero and see if it disengages, then add freeplay until you find the sweet spot.

Right now I can push the clutch lever all the way to the housing even if I took more play out I would not be able to push any further.

Note: I don't understand the need for a "weak link" in the clutch release mechanism. The only forced applied is from the driver's foot. If something is jammed you would feel it, and unless you are a Gorilla you wouldn't keep pushing until something broke inside.... would you? I didn't weld the entire thing, I just put a 3/8 inch tack on the edge of the shaft to the edge of the clutch pedal arm. If I ever need to, it would take about 30 seconds to grind it off. The tack just prevents any slop in the pin because even a tiny bit of slop in that pin can throw the clutch WAY out of adjustment.

Gene :^)

I just mentioned not welding because the inside fork rides on the same type pin setup, just uses 2 instead of 1 like the outside. If the outside pin is as weak as they seem then making it too strong{weld, hard bolt}could easily shear the inside pins, possibly. This is just a thought and it may never happen but it would still be easier to replace a shear pin outside then to have to tear down the machine. I understand you only tack welded it but I'd be willing to bet that tack is stronger then the inside pins ???? I'm not judging your repair, just stating a possiblity that may occur, it may hold up for years

Gene :^ I'm editing because I forgot to finish answering part 1 of your answer. I tried it multible times against the tree. I would put the blade against a tree and push in the clutch it would work for a short time then begain to grab. I would shut it off then restart in reverse, drive it around a bit and do it again each time it did the same thing.

 

[20 20]

Diamondpilot, Bob Rooks; I was wondering if I should try something like that wash down the clutch with many cans of brake/parts cleaner, I quess your also correct at this point what would I have to lose?

If I do end up tearing it down is there a better clutch out there, I have heard that a clutch could be made up of better material?

 

[20 20]

ultrarunner; Thanks for the input, I'm wondering if the water froze and caused some unseen damage inside? I'll try the brake cleaner thing 1st and see what happens, if that doesn't work, then when I tear it down I'll try to get some pictures and post what happened.{if i can work the camera :confused2: :laughing:

 

[Bob Rooks]

If I do end up tearing it down is there a better clutch out there, I have heard that a clutch could be made up of better material?

You can take it to your local brake & clutch shop, they should be able to fix you up with the correct diameter and thickness friction material. Also bear in mind to check the pressure plate for trueness and finger wear. You also have the option of purchasing a new OEM clutch assembly.

 

[Gene :^)]

Sound more and more like there really is a problem internally.

If your clutch plate fell apart and is doubled up making it extra thick so it won't disengage then you would have suddenly had excessive free play in the clutch pedal, did this happen? Did it have little free play when it was working then suddenly have more free play when not working?

When you press the clutch, do you feel the same tension now as you did when it was working?

If you take all the free play out, you should press the clutch and feel the spring resisting you more and more up to a point where you over extend it, then it should become a little less resistance.

It is all about feeling, I would try to get a friend (that is mechanical) to put a fresh set of eyes and hands on it for another opinion before the hassle of taking it apart.

Note: I think the whole shear pin in the clutch linkage anywhere is just a poor design. Cars and Trucks do not use them, the linkage is all solid and there is no need for a weak link. The clutch on a tractor has no special needs that would require a weak link. If the clutch were to jam the weak link should be your foot feeling a problem and not mashing it.

Note 2: If the shear pins inside are going to fail, they will regardless of what is going on outside. My shear pin was failing just from normal use, so I got rid of it. If a situation arose where the clutch jammed and you applied excessive force to the pedal which sheared the pin on the outside and saved the pins on the inside... what good is that? You still need to open the tractor and find out what jammed the clutch. So in my case, I would shear the pins on the inside and just weld those up while I am in there fixing the clutch. If the clutch is working normally and the pins just failed because they are cheap and weak, that will happen no matter what is on the outside joint (be it a working roll pin or a bolt and tack weld).

Note 3: I am not pushing anyone to weld the linkage, I am just arguing the need for a "weak link". Weak Links are used in areas where overload is possible and protection is needed. There is no reason for clutch pedal overload.

Gene :^)