L35 - Lost Front Wheel Drive

[Harley Monster]

I have been working my L35 hard the last few weeks moving rocks with my grapple.

This evening I had a rock in the grapple and was maneuvering over some rough terrain when there was a loud pop from the front of the tractor and I lost my Front Wheel Drive.

It was almost dark by the time I got the tractor back to the house and I have not had a chance to do any troubleshooting.

I have the L35 Workshop Manual and the L35 Illustrated Parts List, I do all my own repair and maintenance.

I have been searching this forum for a like problem but have not found any threads.

I really need to get this tractor repair and back in use ASAP. Do any of you have any tips on what to look for? I will put the tractor on jack stands tomorrow and probably start in the driveshaft area.

Any help would be greatly appreciated.

 

[WinnieCouple]

Sorry to hear of your issue, my front end is not pulling either (since i purchased the tractor) I wasnt able to "test" it enough before i bought it...

I have heard that with both front wheels off the ground, you should NOT be able to spin one freely from the other. Mine WILL spin with no resistance to the other.... so maybe mine is in a front differential.

I hope to draw more attention to your post, so we may both learn more....

 

[Harley Monster]

I will post here as I figure this out WinnieCouple. I hope I will be able to help you.

 

[pat331]

Harley, I have an L35 with just over 1000 hours and have not had that happen to mine. My front drive does seem to bind up when it is locked in and especially in a turn. I always try to shift mine out as soon as I can after loading the FEL or similar operation. Please let us know what you find out. Sorry I couldn't be of more help.

 

[Harley Monster]

First off, I want to tell you guys that my Kubota is a high time machine and its first home was a rental yard per Kubota's records. This tractor had far from tender loving care and if you take good care of your tractor you will not have the problems that I have had. BUT, the price was right and the tractor has served me well.

Secondly, when I repair something I always try to bring it back up to factory new standards. If I keep doing this on this old Orange I will soon have a new tractor.

I found the cause of my problem, but have not finished taking it apart so I don't know if there is additional damage.

My problem started with the front pillow block the axle pivots on. Kubota call this the Front Assembly Holder which has the bolt and jam nut you use to tighten the front axle. One of the two bolts which holds this block to the tractor came out, the pillow block then pivoted to the side and the axle came out of the assembly allowing the axle to be propelled forward by the front drive wheels. The pop I heard was either the axle popping out of this assembly or the front driveshaft disconnecting from the coupler. or both.

I have not pulled the front wheel driveline apart yet, but I am hoping all that has happened in there is the propeller shaft has pulled out of the coupling.

This tractor has had numerous non-precission field repairs done to it, but I guess they always got it up and running without purchasing or waiting for the proper parts.

For example there is a bushing in the front pillow block that is pretty much history and needs to be replaced, but somewhere along the line someone has welded on the boss that fits into this bushing. You can see the welds, how they got it "round" enough to fit back into this housing I will never know. It would be impossible to put it on a lathe so I guess they are better mechanics than I am.

What this tractor really needs is a new front axle housing and new front and rear Assembly Holders and this section would be new again.

Right now, I am going to scab it together so I can use it because I am in the process of building a fairly large garage/barn to work on my equipment and be able to store them inside. Once this building is complete I will tear the entire front end off the tractor and rebuild this failed section and the steering.

Those who have L Series tractors should check that the bolts attaching this Assembly Holder are tight. This will be more evident when I post the photos.

I will post photos later, hopefully tonight.

 

[WinnieCouple]

my front assy. had one sheared bolt that i was able to get out, and the other is stripped.... not an easy place to get a tap in.

these are on the left side (from sitting on the seat).
the other side, has the oil filter adapter and would be a BEAR to get to.
(then again, my rig is a L245DT too)

I hope to be able to pull the lube fill plugs on the axle housings, and with the front wheels off the ground, be able to stick my fingler in the housing, touch the axle, rotate the wheels, and hope to feel the axles move, to narrow it down to the front diff, or shear pin..... (wishfull thinking)

 

[Harley Monster]

If you had fastener problems with your front assembly too Winnie, it might be a good idea for everyone to check these fasteners. If your bolt sheared there is a good chance it came loose first.

 

[WinnieCouple]

If you had fastener problems with your front assembly too Winnie, it might be a good idea for everyone to check these fasteners. If your bolt sheared there is a good chance it came loose first.

sounds about right... there was a lot of movement in the front end.
I was able to get the broken bolt out and replace it, but the second bolt (the bigger of the 2) is stripped out.
With it being in a tight area... it will be tuff to tap. ( i keep snugging it back down, its already had a helicoil put in it, found pieces of it...)

 

[Harley Monster]

Winnie, I am not sure yours is the same as mine, both the bolts that hold this assembly to my tractor are the same size, 14-1.5 X 40.

My problem must be different than yours too because with both front tires off the ground if I turn on wheel the other side goes in the opposite direction as any unlocked differential will do.

I recently rebuilt both front hubs and that was pretty easy, but I didn't get into the differential. If you don't have the Shop Manual and the Illustrated Parts List I really recommend you get them, they will more than likely pay for themselves the first time you use them, mine sure did.

To Check my driveline I jacked up the axle and pushed it rearward and it went right in. I thought I would do a quick check to see if the driveline disconnected by jacking the rear tires off the ground, front tires removed to see if I got any rotation of the front hubs by running it in 4 Wheel Drive. Neither front hubs turned so I am assuming the driveline splined shaft, Kubota calls it the Propeller Shaft, pulled out of the coupler. My next step is to get into the driveline.

 

[Harley Monster]

Oh, No! Big time broken!

Oh, No! Big time broken!

I just pulled the driveline apart and it is the worst of the worst, or badder than bad!

The pinion shaft is broken!

Kubota calls it the bevel gear, but it is still broken.

I mentioned earlier of a poorly done field repair on the main axle housing bosses (I can't think of a better word for them) where the axle slips into the Assembly Holders front and rear. Ironically, I am having some grading done on the property and I had the grader look at it and he said he has the man for me. He says he can weld the bosses (to make them larger) then has a way to machine them on site and he says he is CHEAP and does good work...did I hear magic words?

I am going to have to order new assemblies from Kubota, new Holders, and a pinion assembly. while I am at it I will order new driveshaft covers as these have a very poor repair on them, welding that looks like bird droppings. I swear, my wife could do better.

I promise to have photos for you guys! Let me get cleaned up and fed first.

 

[hodge]

Sorry to hear of your issue, my front end is not pulling either (since i purchased the tractor) I wasnt able to "test" it enough before i bought it...

I have heard that with both front wheels off the ground, you should NOT be able to spin one freely from the other. Mine WILL spin with no resistance to the other.... so maybe mine is in a front differential.

I hope to draw more attention to your post, so we may both learn more....

What you heard is not completely true. If the 4WD is engaged, and the front wheels are off the ground, then when you spin one wheel, the other one will rotate the opposite direction. If something is broken, then one will spin, and you should hear noise in the center section. Remember, that is if the 4WD is engaged- that would keep the front driveshaft from turning. But, if it is in 2WD, and you spin a tire, either the driveshaft will turn, or the other tire will turn backwards, or a combination of both- that will not positively tell you if you have a problem in the front end. The only way to tell is if 4WD is engaged. Make sense?
The only variation to this is if you have a limited slip or locking differential, but most of these small tractors do not. If you did, then with the 4WD engaged, you would either feel great resistance (limited slip), or you wouldn't be able to turn the tire.

 

[WinnieCouple]

My L245DT DOES have a locking differential, via spring loaded pedal. Works well.
The lever to engage the front wheels however, has no resistance when moved to the 4wd position... so, the fork "may" be bent...?
and again, the front wheels will spin freely (by hand), with no noise or resistance, when raised off ground, (have NOT tried with 4x4 engaged), so... where its broke, I do not know..
I dont have time to pull it apart, as i'm using it in 2wd, with good results pulling a box blade and using the FEL for clearing our build site.
I just thought some day, i'd raise it and pull a fill plug and stick a finger on the axle and spin a wheel, just to see if the axles spin (if there are even axles IN the front end...???)

even with only 2wd, she is a little work horse. having the 4wd fixed will be nice, I'd just like to narrow it down as much as i can, before i go pulling it apart. (to have an idea what kind of cost to expect) so, all input/advice is taken to heart. THANKS.

 

[WinnieCouple]

Re: Oh, No! Big time broken!

Oh, No! Big time broken!

The pinion shaft is broken!

Better the pinion shaft than the pinion GEAR, where the ring gears would get ate up too.... ( my opinion anyway)
so, from what i see, does your front drive shaft have the bevel gears (pinion?) on both ends?
It does sound like something that could be welded back and cleaned up to work if broken clean in the middle...?


I may be totally out of the ballpark, but its sure not like any jeep or 4x4 i've tinkered with before, so dont mind me... i'm just learning.

 

[Harley Monster]

I will know more when I pull the axle and the pinion out which I may not be able to do for a couple of days. I agree, if the pinion gear is damaged I will have to take the entire front axle apart.

The Illustrated Parts Manual shows splines on both ends of the segmented driveshaft coupled by splined couplers. Stay tuned, I will show you photos when I get it apart.

 

[WinnieCouple]

I will know more when I pull the axle and the pinion out which I may not be able to do for a couple of days. I agree, if the pinion gear is damaged I will have to take the entire front axle apart.

The Illustrated Parts Manual shows splines on both ends of the segmented driveshaft coupled by splined couplers. Stay tuned, I will show you photos when I get it apart.

OK HM, keep us posted. I thought I was having hyd problems, yesterday NOTHING worked (FEL, 3pt).... Today, its fine...???

 

[Harley Monster]

I had a devil of a time getting the broken pinion out of the front axle housing.

There had been a "field repair" of both of the bosses the front axle pivots on, they had been welded to make them larger, then crudely ground to make them roughly round. This axle must have really been abused.

I followed the shop manual which says to remove the plug in the front boss and use a brass drift to tap out the pinion. Yeah, right.

None of my brass drifts were small enough to go through this hole, it was only about 7/16", I found some 3/8" rebar which is a very soft metal and attempted to "tap" the pinion out. I tried a hammer, a bigger hammer and then a BFH with no joy, all it did was bend the rebar.

I found some 3/8" cold rolled rod and applied the hammer, the bigger hammer and then the BFH again with no luck all it did was bend the rod.

I believe the welding on the boss shrunk the metal and captured the pinion bearings.

I pretty much resigned myself that anew housing was in order.

Looking down the axle tube I saw no damage on the differential section or the ring gear, so the pinion had to come out far enough for me to remove the differential. The differential can only come out one way, there is a machined shoulder inside the tube that the differential assembly stops against so it must be removed past the pinion gear.

All my hammer persuation had move the pinion out just beyond the land for the cir-clip, but it had to go about another 3/8 to 1/2" for the pinion to clear the differential.

I asked my neighbor to come over to give me a second opinion and he agreed the housing could not be saved for the cost of a new housing which is $733.

I then took my die grinder type cutoff wheel and cut the pinion boss off the axle, then the differential slid out just like it was supposed to.

I took the cutoff piece with the pinion still in it to my press and it was still no easy task to get the pinion out.

The ring and pinion come as a matched set, just like for a car so the ring gear is the only piece on the differential that will be replaced.

I am about to put in my order for parts, but I am having a problem trying to figure out what size collars to order for the installation of the new ring and pinion. Usually you can buy a shim set when ordering a ring and pinion to play with the pinion depth, but Kubota calls them Collars and they are around 10mm thick and they are about $6.50 apiece and they offer 5 thicknesses for each of the two collar positions. The book says to replace the pinion with the same collars as you took out, but they are assuming only a bearing replacement, not a new gear and housing set. The mechanics at my favorite dealership have not been able to give me any guidance. Perhaps, I should order the middle size for each collar required.

Any experienced Kubota mechanics out there to help me with this?

 

[WinnieCouple]

WOW...
I'm thinking I'll just get a short Dana44 and modify it...!!!
( not really, but wouldnt that be nice..)

Any of these used parts places sell a complete front end? or do you have to piece it back together..?

Well, good luck to you, and hope you get it shimmed up the first try....
I know that can be a PAIN.

 

[Harley Monster]

I called in my order into my favorite Kubota dealer this afternoon, they will call me with the monitary damage tomorrow and let me know if everything is readily available.

My order took up a page and a half on a yellow tablet. Unfortunately I had to order everything by the part, nothing comes assembled.

I checked a few dismatlers to see if they had a front axle for the L35, but none of them had one. Honestly, I would just as soon have everything new.

I talked to two Kubota mechanics at the dealership about what collars to use (shims) to use on the pinion assembly because everything will be new, the case and the ring and pinion. The only advice they could give me is to use the same sizes as came out of it. That is fine is you are only replacing the bearings, but it is just a guess when you are replacing both the case and the gears.

There are 5 sizes for each of the 3 positions the collars are used. The mechanics told me that the first and the last are usually the same size. I ordered the middle size for both positions that differ. I ordered a 10.0 mm for between the bearings and two 6.0 mm collars for the ends.

I think it will work out fine, the machining processes are so much more acurate than they were 20 or 30 years ago, so I am guessing the middle ones are the standard.

 

[WinnieCouple]

I know it would be a lot of trouble, but may be well worth it.
Paint the yellow on the gears, put them together with one set of shimms (not torqued, but not "loose"), rotated it, pull it apart, and check the paint and see where its meshing... (not sure on the total "process", but just old school set up stuff).
Gives you an idea that they are getting a good bite, or not enough/too much.

Sounds like you know what your doing, i'm just tossin ideas out, but you'll get her right i'm sure.

 

[Harley Monster]

Thanks for the tip Winnie.

I will definitely check the footprint on the gears and the backlash, but from what I gather it is not nearly as critical on the low speed driveline on the tractor as it would be on a car. I have done several 10 & 12 bolts and a few 9" so I am comfortable with this. I think you are right though, on this set up it should not be too tight or too loose.