NORTRAC NT-204C FRONT WHEELS NOT ENGAGING

[DUMMASS]

HOW DO YOU DETERMINE WHY THE TRANSFER CASE ISN'T INGAGING?
HELP PLEASE

 

[RonMar]

More details please...

4X4 basics:
1. Clutch is not involved in shifting from 2X to 4X. You are coupling the front differential to the rear differential.
2. Tractor must be rolling when you try to engage. The coupling mechanism looks like a 6 piece pie with every other piece missing. This mates with a duplicate piece. They have square faces so must rotate into alignment in order to engage. In order to rotate into alignment the tractor must be rolling to rotate the parts. Differences in gear ratios, tire size and wether you are turning or not causes the two parts(when not engaged) to rotate at slightly different speeds. that is why 4X causes more soil damage, and why you should never use 4X on hard surfaces as these differences in ratios will cause the drivetrain to bind and wear excessively. Soft ground allows wheel slippage...

To engage 4X4, start driving. While driving along, just hold gentle pressure up on the 4X lever till it slips into 4X. The same process is used when engaging the rear difflock(uses the same parts as 4X mechanism), while rolling, or a rear wheel is spinning, hold pressure on the engage lever till the pawls align and it engages the difflock...

SO is it the way you are doing it, or is it stuck/broken? You can see the 4X4 pawl if you remove the front creeper gearcase cover. You can also see the lever mechanism that comes thru the side case and moves the sliding pawl into engagement with the fixed pawl.

 

[greg_g]

Check the base of the 4x4 lever where it attaches to the horizontal shaft. Make sure that moving the lever also moves the shaft. Often the roll pin that fixes the lever to the shaft will break. If the lever is moving but the shaft is not, drive out what's left of the old roll pin - and replace it with a nested pin set. Not sure of what size yours takes, but a typical nested set would be a 3x25 inside a 5x25. On the chance that your lever connects via cable, the same thing applies - but check the pin at the cable end too.

//greg//

 

[Affordable]

I agree with the above, but most of the time it's as simple as a broken circlip that has let the 8mm ball bearings come out.I would take loose the weldment covering the 4 x 4 shaft, check both couplers for 6- 8 mm balls each, and that the circlip is in place

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

 

[DUMMASS]

THANKS RON,
REMOVED COVER EVERYTHING SEEMS TO BE FUNCTIONING CORRECTLY..........NOW WHAT?

 

[DUMMASS]

EVERTHING SEEMS INTACT...

 

[Rich Waugh]

I all the cases of the front wheel drive not working that I've read about on this and other forums, I've never yet seen one that was the result of a failure inside the transmission or the transfer case. They've always been either a broken roll pin or actuating lever/fork or the coupling balls in the front drive shaft popping loose. Well, with the exception of a couple cases where the front drive shaft or joints actually broke from over-torqueing them by using the 4WD incorrectly, and the operators pretty much knew what had happened when they did that. I

I'd suggest you re-check every connection in the driveline - I'm pretty sure you'll find something broken. When a roll pin breaks you can't see it, you an only tell by marking the arm and the shaft with a scribe and checking for lack of movement of the shaft. This joint doesn't move very far at all, so you need fine marks to determine if it is slipping. Sometimes you can tell by feel by putting your finger over the end of the shaft and arm and having someone else pull the lever so you can concentrate on feeling if the joint all moves as one or is slipping.

With the coupling balls in the drive shaft you have to pull the covers and then the rubber boot thingie and check if the circlip is in place. Just because it is in place doesn't mean everything is fine, though. You really need to remove the circlip and pull the housing back *carefully* and check to see that the balls are in place. Be advised that those balls are not retained in any way so if you pull the housing back carelessly you'll have eight little 8mm ball bearings fall on the ground and get lost. I always work over a tarp or piece of cardboard so I can find them. When re-installing them, a gob of heavy grease will hold them inn place until you get all eight in and can close it up.

 

[RonMar]

THANKS RON,
REMOVED COVER EVERYTHING SEEMS TO BE FUNCTIONING CORRECTLY..........NOW WHAT?

So you can see the lever move the pawl into engagement? If it is engaging, then the problem lies elsewhere. Perhaps the front driveshaft has lost it's marbles as suggested, or perhaps one of the pawls are slipping on it's shaft. Or it has sheared a shaft. There could also be a problem in the front differential/axle. Ususally this type failure announces itself with a loud failure and grinding noises. IF you are able to see the lever engage the two pawls, and you can get the front axle off the ground(I use the loader) this video might give you some things to try to see where the problem might lie. With the access cover off the creeper gearbox to look at teh 4X4 engagement mechanism, you should be able to see the various parts turning.
Jinma tractor drivetrain - YouTube

 

[erj]

RonMar,
Thank you so much for taking the time to make that video!!
I have seen this process described in words many times, but now I can really understand it.
RonJ

 

[greg_g]

I all the cases of the front wheel drive not working that I've read about on this and other forums, I've never yet seen one that was the result of a failure inside the transmission or the transfer case. .

Guess you forgot about the time I had to rebuild the transfer case on my KM454. The transmission front drive gear and the transfer case driven gear chewed each other up and bent their respective shafts in the process. All four pieces had to be replaced, along with the associated bearings and seals. It was a 2wd tractor for quite a while before I got all the parts together to tear it down and fix it.

//greg//