Jinma 284 PTO issues

   / Jinma 284 PTO issues #1  

dunerdr

New member
Joined
Oct 23, 2011
Messages
4
Tractor
Jinma 284
I recently obtained a Jinma 284 with about 600 hrs. The previous owner said that they had just put a clutch in it. The tractor drives fine but the PTO is not working properly. When engaged in either the 540 or 1000 rpm modes is clearly does not spin fast enough and can be stopped simply by putting your shoe against the shaft. I pulled the loader brackets off and the clutch does appear to be new, and both the PTO levers are engaged(engagment lever and speed lever). The tractor did not come with a manual so im not sure if it could be a clutch issue or possibly something in the hyd auctuation/levers for the PTO engagment(again i do not have a manual so i'm not totally sure how the PTO operated on these tractors).
 
   / Jinma 284 PTO issues #2  
There are no hydraulics associated with either the PTO or the drive clutch. That the PTO stub is rotating without being physically engaged is normal though, caused by parasitic fluid motion inside the transmission

And when the previous owner said "they had just put a clutch in it", well that could mean many things. They may have just replaced a friction disc or discs. But to try and narrow this down, I'd like you to disengage the PTO lever. Then start the tractor, push in the clutch, re-engage the PTO lever, and tell us the results. If possible it would also be quite helpful to get some details from the previous owner with a few more specifics as to how they define "put a clutch in".

//greg//
 
   / Jinma 284 PTO issues
  • Thread Starter
#3  
They said that they bought a complete clutch... but I wasnt there so i'm not sure. It look new whrn viewed from the bellhousing covers but thats not saying much.

Starting the tractor with the pto disengaged is does not turn. When the clutch is depressed and PTO engaged it will spin but can be stopped by pressing foot against the shaft.
?I think that answers your question?
 
   / Jinma 284 PTO issues #4  
It is a 2 stage clutch. When the pedal is depressed, the throwout bearing pushes on the 3 fingers/levers and lifts the rear pressure plate that clamps on the main drive disc. As you continue to push on the pedal, the main pressure plate will eventually start to lift the PTO pressure plate and release that disc. As you release the pedal, the PTO cluch should engage fairly close to the bottom of the pedal travel. At about 1/2 of the pedal travel as you are releasing the pedal, the PTO should be fully engaged and the main clutch disc should be starting to engage the main drive gears. The relationship between the parts is adjustable, but if not setup correctly could be holding the PTO pressure plate open. My first check would probably be to start it up, put it in gear, and slowly let out the pedal and note at what point in the pedal travel does the tractor start to roll. It should happen at about the middle of pedal travel. If it does not, i would suspect a misadjusted clutch.

The PTO shaft runs thru the middle of the main shaft in the gearbox. The friction of the oil inside the shaft couples some torque from the outer shaft to the inner PTO shaft(causes the spinning that you can stop with some force applied to the PTO shaft). This torque must pass thru the engage/disengage gear controlled by the lever down by your right heel when seated on the tractor. When disengaged, my PTO shaft does not rotate at all, and yours should work the same way. So if yours is spinning when engaged, I would say that engage/disengage selector is working. When engaged, the PTO torque passes to the 540/1000 gearbox all the way in the back. Because of the design of the speed selector gearbox, my PTO output shaft spins regardless of the position of the 540-neutral-1000 lever(located below right hand 3PH upper lift arm) due to oil friction in the 540/1000 gearbox. Perhaps that gearbox is not engaging on yours. Another easy check is to remove the large access plate immediatly above the PTO output shaft. That plate covers the end of a slotted shaft used to drive a PTO pump when using a BackHoe. That shaft with the slot in the end spins at engine RPM and when the engage/disengage lever is engaged, it is coupled directly to the PTO clutch disc. That shaft drives the 540/1000 gearbox So with the engine OFF, and the engage/disengage lever engaged, insert a large screwdriver or bar into the end of the slotted shaft and see if you can rotate that shaft. If you cannot, then the PTO clutch may be engaged. Have someone depress the clutch pedal fully and try to turn the screwdriver again. You may need a wrench on the screwdriver/bar to apply enough torque to overcome disc friction. You should be able to turn the shaft with the clutch fully depressed. If it works like that , then the problem is in the 540/1000 gearbox. If it can be turned with the clutch pedal released, then the clutch is probably the issue.

To check the 540/1000 gearbox, With a screwdriver holding the slotted shaft in place, you should be able to rotate the PTO shaft with the 540/1000 lever in neutral. You should not be able to rotate the PTO shaft while holding the slotted shaft stationary in either the 540 or 1000 RPM positions.

Here is a sight you may find usefull. johnstractor On the left, Click on Jinma info, then Jinma maintenance info. On the right hand colum you will find 254(same as 284) engine and gearbox exploded views. In the center colum, at the bottom you will find a link to a clutch adjustment procedure.

Good luck.
 
   / Jinma 284 PTO issues #5  
Sounds like you are going to have to confirm the clutch adjustments first,if they are ok the next step is the spline sleeve and the shift lump which is under the hydraulic lift box.If you want some help confirming the clutch adjustment send me a e-mail,I will be glad to try and help you with it

tommy@affordabletractorsalesco.com


Tommy
Affordable Tractor Sales
"Your Jinma Parts Superstore"
Home of compact Jinma, Foton, and Koyker Tractors and Parts, Wood Chippers, Backhoes - Affordable Tractor Sales Company
 
   / Jinma 284 PTO issues #6  
Before you go too far on the clutch, my Jinma has two levers to engage the PTO: one to the left of the driver's seat, which has three positions, fast-off-slow, and one under the driver's right heel. The one on the right you pull up to engage and step on to disengage.

If one lever is engaged but not the other the PTO shaft will spin slowly.
 
   / Jinma 284 PTO issues #7  
I seem to be having the same problem. When engaged , the PTO will turn but I can stop it with my hand. (I know, not a smart move but it has no torque)
I had the 16” shaft replaced but didn’t change the spline sleeve. It worked for a while but now I have the same problem. The shop pulled the loader and took a look at the clutches and pronounced every thing OK. Rather than pay the shop to do the repair ,I’ll do it myself. The shop has worked on my tractor 4 times and have only fixed the problems twice, not a good enough average. I have ordered the sleeve and gaskets as well as a new seat. They should be here this week as Circle G says they are all in stock. We will see.
 
 
Top