L3940 leaking from bellhousing

fordtruck03070

New member

Equipment
L3940 FEL, backhoe, york rake, bush hog
Sep 15, 2019
5
0
0
NEW BOSTON, NH
Hi guys and gals! My first post here and first major work on my tractor....

So, started with a leak from bellhousing. After all the research I did, I came up with front output shaft seal. Split tractor and changed. Couldn't see anything wrong with seal, but for $7 I changed it. While I was in there, did all maintenance, all filters, oil. Suction filter magnet had some "what I'd call drill shavings" on it, which concerned me. Tractor has 1180 HR on it.

After all this, did about 3 hours of bush hogging and raking driveway, Not a single leak. Hooked loader back on, almost immediately leaking like a sieve from bellhousing again!

ANY help would be greatly appreciated! I'm at my whits end with this tractor!
 

eserv

Active member

Equipment
BX24, A1000 Kubota Generator
May 27, 2009
1,883
12
38
Hardisty, Alberta
Hi guys and gals! My first post here and first major work on my tractor....

So, started with a leak from bellhousing. After all the research I did, I came up with front output shaft seal. Split tractor and changed. Couldn't see anything wrong with seal, but for $7 I changed it. While I was in there, did all maintenance, all filters, oil. Suction filter magnet had some "what I'd call drill shavings" on it, which concerned me. Tractor has 1180 HR on it.

After all this, did about 3 hours of bush hogging and raking driveway, Not a single leak. Hooked loader back on, almost immediately leaking like a sieve from bellhousing again!

ANY help would be greatly appreciated! I'm at my whits end with this tractor!

The usual reason this series of tractor leak from the bell housing is that the sleeve on the front wheel drive drive shaft slips forward out of the seal!! There is a sleeve kit from Kubota to eliminate this problem. you can push the sleeve back into place and install the kit without splitting the tractor.
 

D2Cat

Well-known member
Lifetime Member

Equipment
L305DT, B7100HST, TG1860, TG1860D, L4240
Mar 27, 2014
9,246
430
83
40 miles south of Kansas City
Are you positive where the leak originates? On my L4240 I noticed some hyd. oil on lower parts under the transmission. I cleaned everything with brake cleaner and then watched to determine where it was coming from.

What I discovered was under the steering wheel, uhder the floor board is a banjo fitting that is the return line to the cooler in the front. The washers were not sealing there.

I removed the floor mat and then the shield that has three screws. There are a couple of rubber boots that cover the holes you would need to get to.

Maybe not your problem, just a heads up.
 

fordtruck03070

New member

Equipment
L3940 FEL, backhoe, york rake, bush hog
Sep 15, 2019
5
0
0
NEW BOSTON, NH
Are you positive where the leak originates? On my L4240 I noticed some hyd. oil on lower parts under the transmission. I cleaned everything with brake cleaner and then watched to determine where it was coming from.

What I discovered was under the steering wheel, uhder the floor board is a banjo fitting that is the return line to the cooler in the front. The washers were not sealing there.

I removed the floor mat and then the shield that has three screws. There are a couple of rubber boots that cover the holes you would need to get to.

Maybe not your problem, just a heads up.

No, It is definitely leaking out of bellhousing. Out of weap hole, and front drive shaft sleeve. I don't get it, cause I can operate tractor for hours with no problems. But if I put loader or backhoe on it leaks.
 

kevinj

Member

Equipment
L3940hstc - B7500hst - BX1860 - Farmall 560D - Farmall M
Jun 4, 2018
85
2
8
Michigan
I think it is the trans input and there is an updated housing that needs to be put in.
 

lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
2,517
140
63
Mid, South, USA
Had a GL 40 series a while back....HST....the HST was trashed, excessive pressure in the charge pump due to worn shafts/bearings/seals. Similar complaint. Peeing oil out of the clutch housing but worse while running.

Typically the propeller shaft seal leak (the INFAMOUS leak) will leak mostly with the engine not running; however if an HST or trans issue, it'll leak more with the motor running.

So how was the HST trashed? Well after months of trying to figure it out, we finally got the rest of the story. Owner said that the battery was dead (and we knew it was, we had to jump it every time we needed to start it), and he was PULL STARTING it with another tractor. Well that doesn't work very well with HST's. That's what started the process. $6500 repair, preventable by replacing a $150 battery. I didn't even know it was possible to push/pull start an HST transmission equipped tractor. Guy said he'd have to get it rolling pretty good to get it to turn over enough to start. I'm like ARE YOU SERIOUS????

--you can't fix it.
 

fordtruck03070

New member

Equipment
L3940 FEL, backhoe, york rake, bush hog
Sep 15, 2019
5
0
0
NEW BOSTON, NH
I think it is the trans input and there is an updated housing that needs to be put in.

Why would trans input only leak when loader or backhoe are used? I ran for 3+ hours with bush hog and york rake, no problems....right when I put loader on it started leaking bad!
 

kevinj

Member

Equipment
L3940hstc - B7500hst - BX1860 - Farmall 560D - Farmall M
Jun 4, 2018
85
2
8
Michigan
Why would trans input only leak when loader or backhoe are used? I ran for 3+ hours with bush hog and york rake, no problems....right when I put loader on it started leaking bad!

I have no idea about your exact leak but when I fixed mine the dealer showed me the bulletin for this updated cover(about $35.00 I think)

Mine leaked mostly after heavy PTO use and it takes awhile for it to start dripping.

They claim that they have had no repeat leaks since using the new housing.

Mine is still dry over a year now.