Jinma 254 - General Operational Question

[ljplum12]

Since this is my first time owning a tractor and first time piloting one (besides a lawn mower) since I was a youngster, there are some things I'm not really sure about operationally, particularly regarding gearing.

The tractor doesn't stall. If I put it in a gear and let off the clutch, it won't move, but it won't die either. Is this normal? How is it different than a car?

I don't know how well this thing is supposed to move across the terrain, but I feel like it's lacking in getting the power to the wheels. With the slightest incline I can't really get it to move above 2 H/L. Is this normal as well?

It seems people don't typically just go out and buy a tractor without having some kind of experience, so I can't find a "Introduction to how to drive a small tractor" anywhere. :laughing:

 

[RonMar]

Not quite understanding what you mean. Does it not move at all or only has issues on an incline.

Basically you have 3 levers to deal with.
1. The main gear lever(1,2,3 and R).
2. The High/low lever down in front of the seat(right and slightly to the rear of the main lever).
3. The Low/Low or "creeper" lever(all the way forward on top of the transmission).
On some models the creeper is replaced by a shuttle shift gear with a linkage up to a F/R lever under the steering wheel. If it is not moving at all, are ALL the gear levers fully engaged?

 

[ljplum12]

It moves pretty well on flat surfaces. Today I was moving some yard waste around and on slight inclines (or even just going over small humps) in order to get it to move I would have to put it in (matching up with your explanation):
1. Main Gear Level - 1
2. High/Low lever - Low
3. Low/Low - Bunny Rabbit (not in creeper)

Due to my inexperience, I don't know if this is normal for this tractor.

 

[RonMar]

OK, that does not sound normal. You should be able to drive just about anywhere in 1/high/high. That is my normal mode even on hills with a bucket full of soil and a grader blade on the back.

it sounds like you either have a clutch problem or a clutch linkage/adjustment problem. To look at the adjustment you need to remove a side access plate. Unfortunately if you have a front end loader the loader mount is usually bolted over the access hole/where the access cover is located. Most loaders are setup so you can remove that loader bracket with only having to support the crossbar with a jackstand.

What you are looking for first is that the throwout bearing is completely dis-engaging the 3 fingers of the pressure plate assembly. When you depress the clutch pedal a fork pushes the throwout bearing forward into the fingers. The fingers act as levers to release the pressure on the clutch disc. The throwout and fingers are on the rear of the assembly and when the clutch pedal is released, there should be about a 1/8" gap beteen the bearing and the fingers. If you have this gap, the clutch fingers may be out of adjustment or the clutch pack has failed. There are some articles written how to adjust it but you should be familliar with mechanic work before you proceed.

 

[redman135]

I 2nd RonMar. That sounds wrong.
When you let the clutch out on a gear tractor you start moving, the speed depends on which gear you are in.

 

[ljplum12]

I have made some adjustments to the clutch based on articles and tutorials, obviously it's still not right.

A couple days ago I set the gap between the throwout bearing and fingers to 1/8" and verified all three fingers had the same gap. I did this by adjusting the linkage.

That must mean I need to adjust the clutch fingers themselves. This video (how to adjust the clutch on a tractor, jimna 254 xl sl 2 tractor clutch adjustment - YouTube) suggests I do that by setting the gap to 10mm. Is that accurate?

 

[ljplum12]

From my reading, if the clutch is slipping, that means I need more pressure on the plate. None of the articles I've found indicate how to do that, they're all how to set the free-play. Is adjusting this gap here how I get more pressure?

 

[ljplum12]

Ok, I think I understand this now, and if someone could let me know if I got this right, that would be great.

• For the main clutch, there are these two measurements ("A" and "B" in photo) that can be made on all three fingers.
• They are tied together (adjusting "A" will change "B").
• The actual measurement of "A" does not matter, only "B" matters (needs to be set to 0.10").
• "A" is changed by loosening the jam nut and turning the bolt.
• The narrower "A" is, the more pressure there is.
• "B" is changed individually on the three fingers the same way, but overall can be set with the clutch linkage.
• If "B" is set to 0.10" and the clutch is slipping, this means "A" needs to be reduced (more pressure).
• All "A" should be adjusted X amount of turns to increase the overall pressure.
• Once all "A" have been adjusted, the clutch linkage should be adjust so that the smallest of the "B" gaps is 0.10"
• With one "B" gap set to 0.10", small adjustments should be made to the other two fingers so they are also 0.10"
• This means that "A" will not be the same on all three fingers, but this is ok, the don't have to be.

Is my understanding correct on all of this?

 

[Ricks284]

Be careful with clutch adjustments - it's really easy to get it adjusted slightly off center and have the clutch plate wear unevenly. Mine was adjusted wrong from the factory and it ended up needing an entirely​ new clutch.

 

[ljplum12]

As long as the distance between the throwout bearing and fingers are all the same I'm good, right?

 

[quicksandfarmer]

If the tractor is operating properly it should maintain a constant speed in the same gear with the engine at a constant speed. The engine speed is regulated so it should remain constant. So if you put the tractor in gear and don't touch the throttle you should head off at constant speed over hill and dale. The only exception would be if the hill is too steep or the load too heavy and the engine can't keep up. If that's happening the RPM on the tach drops, and the regulator should be dumping fuel into the engine trying to get back up to speed, and you have billows of black smoke.

If the engine speed is constant and the speed isn't, it means your clutch is slipping. The only clutch adjustment is the free play, to make sure that when you have your foot off of the pedal it isn't pressing on the clutch release at all. There is no adjustment to increase clutch grab, maximum is the pedal all the way free, that's it. If your clutch is slipping when the pedal is untouched and you have a good gap, your clutch needs to be replaced. The plates have worn to the point where they are too thin to make full contact.

 

[Ricks284]

As long as the distance between the throwout bearing and fingers are all the same I'm good, right?

Yes, I think so... but hopefully someone with more experience can chime in here.

I tried to do the adjustments to my old clutch exactly like you are describing, and I was very careful to turn each bolt exactly the same amount. My clutch worked fine for the transmission, but I couldn't get the PTO to engage. I finally gave up -- I couldn't get the PTO and transmission to both work at the same time (with my old clutch). So I just set it for the transmission to work, and asked the dealer to look at it the next time it was in the shop. Looking back, I think my clutch plate was worn unevenly, and I probably had no chance of getting it adjusted correctly.

After replacing it with a brand new clutch, the dealer told me that the range of adjustment was approx one-eighth of a turn from working to not working (for the PTO). He had the tractor on a dyno while he was doing the adjustments, so he was absolutely sure that the transmission was losing power when he got out of that adjustment range.

I don't know if that is normal or not, but that was my experience with it -- YMMV.

 

[Ricks284]

Deleted duplicate post

 

[Ricks284]

Duplicate post

 

[quicksandfarmer]

If the tractor is operating properly it should maintain a constant speed in the same gear with the engine at a constant speed. The engine speed is regulated so it should remain constant. So if you put the tractor in gear and don't touch the throttle you should head off at constant speed over hill and dale. The only exception would be if the hill is too steep or the load too heavy and the engine can't keep up. If that's happening the RPM on the tach drops, and the regulator should be dumping fuel into the engine trying to get back up to speed, and you have billows of black smoke.

If the engine speed is constant and the speed isn't, it means your clutch is slipping. The only clutch adjustment is the free play, to make sure that when you have your foot off of the pedal it isn't pressing on the clutch release at all. There is no adjustment to increase clutch grab, maximum is the pedal all the way free, that's it. If your clutch is slipping when the pedal is untouched and you have a good gap, your clutch needs to be replaced. The plates have worn to the point where they are too thin to make full contact.

 

[Ricks284]

Good luck with it!

 

[quicksandfarmer]

If the tractor is operating properly it should maintain a constant speed in the same gear with the engine at a constant speed. The engine speed is regulated so it should remain constant. So if you put the tractor in gear and don't touch the throttle you should head off at constant speed over hill and dale. The only exception would be if the hill is too steep or the load too heavy and the engine can't keep up. If that's happening the RPM on the tach drops, and the regulator should be dumping fuel into the engine trying to get back up to speed, and you have billows of black smoke.

If the engine speed is constant and the ground speed isn't, it means your clutch is slipping. The only clutch adjustment is the free play, to make sure that when you have your foot off of the pedal it isn't pressing on the clutch release at all. There is no adjustment to increase clutch grab, maximum is the pedal all the way free, that's it. If your clutch is slipping when the pedal is untouched and you have a good gap, your clutch needs to be replaced. The plates have worn to the point where they are too thin to make full contact.

 

[mickstanz]

Not quite understanding what you mean. Does it not move at all or only has issues on an incline.

Basically you have 3 levers to deal with.
1. The main gear lever(1,2,3 and R).
2. The High/low lever down in front of the seat(right and slightly to the rear of the main lever).
3. The Low/Low or "creeper" lever(all the way forward on top of the transmission).
On some models the creeper is replaced by a shuttle shift gear with a linkage up to a F/R lever under the steering wheel. If it is not moving at all, are ALL the gear levers fully engaged?

I don't want to hi-jack your thread, but wondering if anyone could answer this. I have a 2015 Jinma 254, it has the shuttle shift lever up next to the steering wheel that controls forward/reverse. The attached photo shows the rest of the levers.

My question is, is there a diff lock? Or a creeper gear on mine? Maybe I haven't found it (it's new to me).

I have two levers that say Die<=>En, I know that one engages/disengages the pro. Is the other one a diff lock? Can be seen on the left of the High/Low lever in photo.

Question I ask is that I have read that the diff lock on these cheap tractors can be very weak so I plan I never using it, I would like to double check it's not engaged and possibly remove the lever or tie it off.

Picture: https://i.imgsafe.org/4c0e3ef594.jpg

Cheers

 

[Rick52]

The handle in the lower left that is turned sideways is your differential lock.

 

[erj]

I am simply posting this to see if it appears.
I have not been able to view any posts since #10 yesterday, even though it appears that there have been more posted.

I see that this now shows as Post #20, so I am unable to view 9 posts, any suggestions?