Help with repair on MFWD on a JD4100

rsmith02184 · Apr 6, 2012

I was mowing the other day with my JD4100 compact utility tractor and it started making a grinding noise. Brought it into the garage and noticed oil leaking out of the front axle where the drive shaft enters the front axle for what I believe operates the front tires when in 4 wheel drive. It is probably a seal or something. I have the repair manual but I am having trouble even finding the page that talks about how to repair this. I don't know a good repair shop in my area.

Is this something I can repair myself or is this something better handled by a pro?

RoyJackson · Apr 6, 2012

Assuming you have a Deere service manual (and not just the operator's manual), look for anything relating to MFWD, Front Axle or Driveline. It may not tell you exactly how to replace a seal (if that's what the problem is), but should describe how to disassemble the front axle.
The Deere manuals assume one has a degree of mechanical aptitude and can interpret the instructions.
You have to determine if you're up to the job.

rsmith02184 · Apr 9, 2012

I have the repair manual but there are some steps that are vague and since I have never done this before, I am not sure I can do this repair with the info I am given.

Here is a perhaps whacky question for you: I don't have the money right now for this repair (and I can't do without my tractor for the many weeks it takes the local shop to get to the repair) so I was wondering if there is a way I can do a temporary repair on this while I contemplate my options. What I have in mind is, since the MFWD input spline is already removed, can I find something that will plug the whole where the input shaft used to protrude from the front axle? I don't think the opening is threaded, so it would have to be some sort of plug or external seal.

What do you think?

Zebrafive · Apr 9, 2012

Is the input splined shaft snapped off? Or removed? Is there a seal for this shaft that can be removed from then outside of the housing? PICTURES would HELP!!

If the input shaft is broken below the seal or removed, and you can get the seal out, I see no reason you could not cut a thin metal or plastic disc and put it behind the seal. Put some sealant on the edge. This should keep dirt out and oil in.

Now if you have more broken parts inside that can do further damage this is not the thing to do.

RoyJackson · Apr 9, 2012

Without actually seeing what's there, I think Zebrafive has a good idea...

Cantoo · Apr 9, 2012

I had a 1520 ford and wrecked the front spline on it pulling tree stumps. I pulled out the shaft and didn't get it repaired for over 2 years. I put chains on the back and it worked fine for snow removal. PS, it was cheaper to hire a local handy guy to repair the tractor than I could buy the parts for. I told him I was in no rush and he was able to get most of the parts used and only new seals and gaskets.

rsmith02184 · Apr 9, 2012

I am tempted by the suggestions offered here but the idea of just NOT fixing it is not an option because oil is leaking where the input shaft enters the from axle.

I took it all apart today and I can see what happened: the outermost bearing (right behind the seal) fell apart and I believe the pieces of broken bearing, tore the seal to shreds, causing the leak. I don't know what caused the bearing to go. I found a few of the bearings loose in the housing but I couldn't find any remnants of the bearing casing. The only part left of the bearing is the inner most ring which is still pressed onto the input shaft.

Now, more than ever, I want to do the repair myself.

So, a couple of questions:

1). Is there a way to get the ring off that is still pressed onto the input shaft or do I have to order a new shaft? I can spin the bearing ring with pliers but it didn't seen to want to come off.

2). I guess I should try and find any metal shavings that might have found their way into the final front drives but I don't want to take them apart. Is there a way to flush them by using the drain plugs and what would I flush them out with?

3). The outer tube that covers the shaft that goes from the rear output drive to the front input, was damaged at some point. The service manual says to remove it but it goes all around the shaft and seems to be one piece. How do I get that off?

Thanks a lot!
It looks like

yelbike · Apr 9, 2012

1 possibly heat the ring enough and it will slide off or carefully cut it off with a cutting wheel on a grinder.

yelbike · Apr 9, 2012

2. I would first use a long handled magnet to dig around see what comes out. Then you could flush with karosene then new oil.

Zebrafive · Apr 10, 2012

For the bearing ring, you can use a cutoff grinder and grind 3/4s of the way thru. Then use a dull chisel to split it. Dull chisel will act like a wedge and the harded bearing material will break. Dull chisel will also prevent damage to the shaft.

You really have to do a thorough cleaning or other bearings will be ruined. I recommend complete disasemblely.