Green Tractor Talk banner

1 - 16 of 16 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
Had a transmission leak and I traced it to the check valves. Tried new o-rings, still leaked. Sent valves to Ohio to be rebuilt. Upon return, I installed them and they did not leak.
However, when I put everything back together, my tractor would not move in forward or reverse. The brakes are not locked, the valve plungers are definitely down, the fluid
level is good, the clutch is working properly, the implement lever to raise and lower the mowing deck is working fine. Any suggestions??
 

·
Registered
Joined
·
1,050 Posts
If valve plungers are down, they're in the free wheeling mode, so, no, you shouldn't be able to drive the tractor.

First, verify free wheeling knob all the way up, CCW. If so, remove fender deck and gently pull the plungers up on both valves. Plungers should pop up when engine runs, but they may be a little tight from the rebuild process. With plungers up. you should be good to go. Bob
 
  • Like
Reactions: KennyP

·
Registered
Joined
·
6 Posts
Discussion Starter #3
Well, maybe the service manual is wrong. It says the free-wheeling knob should be down to drive and up to free-wheel. Right now, when it is up I can both drive and free-wheel. This scares me because the manual says to free-wheel only for short distances. Is it possible when the valves were rebuilt they weren't reassembled properly?
 

·
Registered
Joined
·
1,050 Posts
I don't have a Service Manual for the 140 so I can't say if it's right or wrong. On later 3xx models, plungers depressed is free wheel mode, plungers up is drive mode.

A comment: Drive tractor for a little, 15 minutes, shut down, let sit for 10 minutes, and recheck level. You may have air in you system allowing you to free wheel AND drive at the same time! Otherwise, it could be wear in hyd motor or possibly rebuilt check valves not seating/holding pressure. When you turn free wheeling knob to drive position, you should have a turn or 3 more with no resistance to rotate the knob. As you turn knob to free wheel, know should get tight/resistance to continue rotating. At least this is how the later 3xx's are and I believe the 140 is the same.

Manual is right on as far as not going far AND NOT GOING FAST when in free wheel mode.

A quick tutorial on what happens inside the hydro. When in free wheeling, those valves divert all fluid from the hydraulic pump into the hydro case and no pressure or flow goes to the hyd motor that moves the tractor. When you move the tractor in free wheel, the differential turns the piston pump, rather than the hyd pump turning the motor. The pistons in the hyd motor end up "pumping" the oil out of the hyd motor and you now have pistons moving back and forth with little or no lubrication. A few 100 feet would not be detrimental, but moving/towing a mile or 3 may be!
 

·
Registered
Joined
·
1,050 Posts
Bruce, I may be incorrect on checking oil level. I found a SM2093 for 140's 30,000 and up. Page 10-20-3 states, "Make final check with engine running
and transmission control lever in neutral."

Can't find anything on free wheeling knob rotational direction, but hyd. schematic indicates plungers up is drive mode. Bob
 

·
Registered
Joined
·
10,689 Posts
What year is the 140?

If the bypass is under the seat you screw it in

If the release is in front of the seat you screw it out.
 

·
Registered
Joined
·
287 Posts
Here's a list of Service, Parts & Owners manuals for the 140's:
Screenshot from 2020-10-19 05-50-29.jpg

I have the OMM46861.
 

·
Registered
Joined
·
137 Posts
My 140 h3 serial number is 055667M, and the free wheeling valve under the seat must be turned counterclockwise to move forward or reverse.
 

Attachments

·
Registered
Joined
·
6 Posts
Discussion Starter #10
Drove the tractor a little bit per rwmeyer's advice. It was surging in reverse. I went forward slowly for about 50 feet and the engine died so I pushed it back to the shop.
This is a 30,000+ model vintage about 1974. I am fairly certain that the free-wheeling knob is supposed to be screwed down tight to drive the tractor. The guy that rebuilt
the valves thinks the free-wheeling valve should be opened CCW to drive. I am waiting for his reply to see if he would have reassembled the valves differently if he thought
what I think.
 

·
Registered
Joined
·
10,689 Posts
Drove the tractor a little bit per rwmeyer's advice. It was surging in reverse. I went forward slowly for about 50 feet and the engine died so I pushed it back to the shop.
This is a 30,000+ model vintage about 1974. I am fairly certain that the free-wheeling knob is supposed to be screwed down tight to drive the tractor. The guy that rebuilt
the valves thinks the free-wheeling valve should be opened CCW to drive. I am waiting for his reply to see if he would have reassembled the valves differently if he thought
what I think.
Above 30,000 must be screwed out.
 

·
Registered
Joined
·
1,050 Posts
Bruce, If tractor only has issues in reverse...surging... it's probably the newly rebuilt vavles. I'm with ryd in that the valve knob should be CCW to drive.

Once tractor is up & running again, try this: Start engine and warm for 5 minutes. With valve knob fully CW, try to move forward and reverse...thinking tractor will not move. Next, turn valve fully CCW and try to move forward and reverse...thinking it will move This will tell you for sure which way is free wheel!

You may still be able to (kinda) easily move the tractor with engine not running and valve not in free wheel. This is an indication check valves are sticking or possibly previous owner pushed/towed it to far/fast and damaged the hyd motor. Because it's surging in reverse, I'm gonna say check valve issue. Remove fender pan, manually push pins down on valves. Start tractor & warm, go 3/4 or full throttle watching pins on valves. BOTH pins should pop up. A few drops of hydro oil around the pins won't hurt either. If both pins pop up and are at the same height, could be hyd motor issue. A quick check the hyd motor is to drive up a hill, the steeper the better! If no hill available, a tree will do! Get help and put piece of wood between frame and tree. At full forward and full throttle, you should spin the tires.

One more thing to check: Turn fender deck over and inspect piece of metal that free wheeling knob pushes on. This may be bent.

Check things out and report back
 

·
Registered
Joined
·
6 Posts
Discussion Starter #15
Reporting back.............Turn fender deck over?? The piece of metal that pushes the plungers down is attached to the fan cover on MY tractor. I have to remove the fender deck to get to it.
The deck has a hole in it that the threaded piece sticks through and the knob screws on. I contacted the rebuilder and he offered to send me another valve so I'll be waiting for that.
One of the valves was sticky and still is. It is my understanding that one check valve is for forward and the other for reverse. So, I think the sticky valve was on the reverse side. When the
replacement arrives and I get it installed I expect my tractor will run as before - Knob open (CCW) free-wheel mode. Knob fully closed to drive. (As per owner's manual and shop manual.)
It will probably be a week or so, but I will report back then. Thanks to all of you who participated in my little drama.
 

·
Registered
Joined
·
10,689 Posts
I’m going to unsubscribe, but I suggest rereading your manual, or maybe the decal on the fender deck.

 
1 - 16 of 16 Posts
Top