Montgomery Ward Limited Edition Industrial/Commercial Twin Cylinder 7 Speed Transmatic Transaxle 18 H.P. 38" Lawn Tractor (Model No. TMO-33931A)

 

(Picture of my Tractor after 18 years of service)


 

I purchased my Montgomery Ward Lawn Tractor at Montgomery Ward at the Parkway City Mall at Huntsville, Alabama. The store no longer remains like many other Montgomery Stores across the map. Montgomery Ward (name only) is still alive in the catalog on-line shopping business. Although, it is not the same company. I think I paid around $1,100.00 for the tractor, so it has served me well since 1989.

The tractor was built by MTD (Modern Tool & Die Company) for Montgomery Ward.

The tractor has served me well for the past 19 years and still runs well after all these years cutting 1.5 acres each weekend and pulling a lawn sweeper when needed to clear the yard of leaves or grass clippings.

Lately, I got the urge to purchase a Cub Cadet 2544 Garden Tractor (MTD owns them too!) when my Montgomery Ward Tractor started to exhibit signs of transaxle problems. It was starting to pop out of the forward gear, making some screeching sounds, gear skipping sounds, and simply stopping in its tracks. It would work in reverse just fine. In fact I had to shift it in reverse to get it going forward again. This is what sent me to start shopping for a new tractor.

Then, I decided to look into the transaxle problem a little further. First, I found a MTD part number 717-761 on the lower half of the transaxle. I found some used transaxles on eBay and some with the wheels still attached because they could not remove them. I had a tough time getting those wheels off the axle myself, but with some penetrating oil and a punch with a surface about the size of the axle I was able to knock them out. All the used prices with shipping were around the $100 range and I decided it was not worth the cost to replace the transaxle. Thus, I proceeded to remove the transaxle from the tractor. There was another MTD part number 717-764 on the top housing. The two numbers were confusing me. These numbers are part numbers only for the upper and lower housing for the transaxle. I pulled out the operating manual for the tractor and found the part number for the whole transaxle assembly to be 717-1050 (Single Speed Transaxle - R.H.) which is now replaced by 753-0539. A quick check on the web revealed that was going to cost at least $450.00 plus shipping and this was definitely out of the question. Most of the people listing the transaxle on eBay and the web called it a 5 speed or 7 speed transaxle. It is indeed a single speed forward and a single speed reverse transaxle. It is the pulley system on the various tractors that provide a variable speed control or so-called multiple gears.

My next step was to disassemble the transaxle to see what was wrong. Prior to disassembly I looked at the mechanical diagram in the operating manual to determine the most probable parts that could cause the problems I was experiencing. Basically, I priced all of the gears and hardware used in the forward gear to get a rough idea. While it was cheaper than the entire transaxle, it was still looking like it could cost around $100 for parts. Still, I was determined, It is the curse of being an Electrical Engineer I guess. We just have to know how things work. I proceeded to disassemble the transaxle.

There were only about 12 bolts to remove to open the transaxle case and see what was wrong. The first assembly I removed was the drive shaft which holds the forward and reverse gear. The problem was quickly discovered when I looked at the bushing near the small gear that is part of the shaft. The Flange Bearing (5/8" I.D x 15/16" Lg) was very worn. One side of this bearing was completely worn off. This explained the screeching sound and also the popping out of gear since the travel of the forward and reverse gear was altered when the shift fork move back and forth. The tractor never popped out of the reverse gear, so this was a simple mechanical problem. There is suppose to be a flat washer between this bushing and the gear built on the drive shaft that turns the differential gear. I could find no evidence that this washer was ever placed on the drive shaft. I searched and sifted through the grease in the transaxle housing and could find no pieces of this washer and I would expect to find some remnants. There were none!

I concluded I have found a manufacturing defect in this MTD transaxle assembly. The good news is the flange bushing only cost $3.13 and the missing flat washer cost $1.35. All of my assumptions prior to opening the transaxle case were unfounded, but this was a good thing since the cost to repair would be much less than expected. Being an engineer type, I also purchased the bushing and washer to replace the ones on the other side of the drive shaft close to the disk brake assembly. Oh yes, anytime I purchase a part I always buy 2 (if they are cheap) so I will have one the next time it wears out in case they are not available. The only other cost was a 10oz tube of grease. The transaxle does not use transmission fluid like many sites suggest. It is only packed with grease and I used the MTD grease under part number 737-0148.

Even though the MTD manufacturing defect most likely caused my transaxle to go bad, it is amazing that it lasted 18 years. When somebody says these MTD tractors are made cheap they are not referring to the transaxle. I was impressed by the thickness of the gears and could not visually detect much wear in the transaxle other than the obvious problem. Hopefully, my newly repaired Montgomery Ward branded MTD tractor will last another 18 years. The only other test is to see if it can pull my newly purchased 40" Brinly plug aerator. This will be the test that determines if I will replace my trustworthy Montgomery Ward (MTD) tractor or not.

Below is a history of repairs on my tractor (excluding wearable items like belts, batteries, blades, etc.):

 

Part No. Replaced Description Year Replaced Cost to Replace
Recurring speed control linkage problem

There is a weak design with the speed control linkage were a ferrule is attached to the clutch brake and pedal assembly. The metal is wearing around the ferrule which causes the ferrule to wear and break. There needs to be a bearing or hardened metal insert between this flange bearing and the mount on the pedal assembly. If I keep this tractor there will be a time when this will need to be addressed by my local machine shop, because I am not replacing this self destructive design.

   
711-0198 Ferrule 4 times  
714-0507 Cotter Pin 3/32 x .75" 4 times  
736-0140 Fl Washer .385" I.D. x .62" 4 times  
Ignition switch failure

The ignition switch failed when starting the tractor.

   
725-0267A Ignition switch 28-MAY-93 11.95
Grass deflector constant damage

The hinge assembly on the chute deflector was constantly getting damaged until I finally took it off and found 2 cheap door hinges at Home Depot to retrofit them. There is no spring, but it works and when they are damaged they are cheap to replace.

~1994  
Engine pulley separated at weld joint

The welded plates on the engine pulley separated around the welded joint. This was either a little rust (not much) or a manufacturing defect. I have since limited washing my tractor to 1 or 2 times a year.

   
756-0424 Engine Pulley ~1995 12.63
Ignition switch failure
The ignition switch failed when starting the tractor.    
725-0267 Ignition switch 13-SEP-95 11.95
Recurring speed control linkage problem

There is a weak design with the speed control linkage were a ferrule is attached to the clutch brake and pedal assembly. The metal is wearing around the ferrule which causes the ferrule to wear and break. There needs to be a bearing or hardened metal insert between this flange bearing and the mount on the pedal assembly. If I keep this tractor there will be a time when this will need to be addressed by my local machine shop, because I am not replacing this self destructive design. They substituted Murray Tractor parts on this visit since they could not match up the part number at the local Hill Lawnmower & Chainsaw store.

   
MUR21920 Ferrule 02-MAY-97 1.67
ROT136 Cotter Pin 3/32 x .75" 02-MAY-97 0.21
HDW475 Fl Washer .385" I.D. x .62" 02-MAY-97 0.20
Front left wheel separated from axle bearing

Axle bearing on front left wheel separated from wheel assembly. They did not have the exact replacement so I settled for a different color wheel.

   
734-0997B-0662 Wheel Rim (Front left) 13-AUG-01 24.20
RO368 Short Valve Stem, Core and Cap (TR-412) 13-AUG-01 0.95
Steering wheel excessive play and battery hold down repair
Steering Wheel Play and battery hold-down repair    
738-0141 Shoulder Bolt 28-AUG-01 1.26
710-0152 Hex Bolt 28-AUG-01 0.55
750-0532 Spacer (Plastic) 28-AUG-01 0.64
717-0622 Steering Gear Segment 28-AUG-01 10.97
741-0225 Hex Flange Brg. .634 I.D. 28-AUG-01 1.06
711-0222 Battery Hold Down Rod (2) 28-AUG-01 3.00
736-0219 Wing Nut (2) 28-AUG-01 0.80
Tie rod damaged by catching front wheel on chain link fence

I bent one of the tie rods by catching the front wheel on a fence pretty hard.

   
923-3018 Joint Assy Ball 26-AUG-03 6.49
912-0711 Nut Hex Jam 26-AUG-03 1.03
912-0241 Nut Hex 26-AUG-03 1.03
936-0169 Washer Lock 26-AUG-03 1.03
711-0613 Rod Tie 26-AUG-03 4.91
Front pivot bar failed at center pivot bearing from mild rust

Front Pivot bar failed due to a little bit of rust or the weld was weak on the center round pivot bearing. This is one of the cheap parts of the tractor. A cast pivot arm would be much better than this formed and welded sheet metal.

   
753-0642-0637 Pivot Bar Kit (Includes 4  941-0659 bearings) these bearing are different than the original design (round versus hex) 16-MAY-04 34.39
914-0101 Pin Intern Cotter (2) 16-MAY-04 2.38
936-0160 Washer Fl (2) 16-MAY-04 2.36
941-0659 Flange Bearing (4) 16-MAY-04 3.64
Deck lever handle damaged by hanging tree limb?

The deck lift handle broke. One day I went to reach for it while cutting my grass and it was bent outward by about 15". I am not sure if a tree limb got it or not, but it needed welded or replaced. The replacement is not an exact replacement and requires the Index Bracket to be replaced as well. The deck lift electrical switch may need to be modified or you may have to pull on the deck lift handle to start the tractor. The retrofit instructions mention nothing about the deck lift switch problem, but you will know when your tractor will not start that something is wrong.

   
17194 Lift Handle Brkt. Ass'y replaced with part number  753-0548 MAY-2004  
Recurring speed control linkage problem

There is a weak design with the speed control linkage were a ferrule is attached to the clutch brake and pedal assembly. The metal is wearing around the ferrule which causes the ferrule to wear and break. There needs to be a bearing or hardened metal insert between this flange bearing and the mount on the pedal assembly. If I keep this tractor there will be a time when this will need to be addressed by my local machine shop, because I am not replacing this self destructive design. They substituted Murray Tractor parts on this visit since they could not match up the part number at the local Hill Lawnmower & Chainsaw store.

   
711-0198 Ferrule 29-SEP-07  
714-0507 Cotter Pin 3/32 x .75" 29-SEP-07  
736-0140 Fl Washer .385" I.D. x .62" 29-SEP-07  
Transaxle failed due to maufacturing defect

The transmission seemed to be going bad. Sometimes the tractor would simply stop in its tracks in the forward gear. If you put it in reverse and then back in forward it would start moving again. Other time it would make a gear skipping sound and you could feel the tractor hesitate and jerk you forward. I was afraid this might be the end of my repairs on this tractor due to the expense of a new transaxle, but I decided to take it apart and found a simple problem with a worn bushing and a missing washer (manufacturing defect that led to the problem).

   
741-0337 / 941-0337 Bearing Flange MAY-2008 3.13
741-0336 / 941-0336 Flange Brg 5/8" id x 3/4" Lg MAY-2008 3.15
736-0337 / 936-0337 Fl-Wash 5/8ID x 1.00ID x .040 Thk MAY-2008 1.35
Engine speed surging up and down in RPM

Right after I fixed the transaxle and cut the grass I was feeling pretty good about my good old tractor. As I started to pull it into the garage, the engine started surging. The following week it started to do the same thing about midway through the yard. There were a few web sites that suggested the engine surge issue was related to anything from cleaning the carburetor, replacing the fuel filter, replacing the fuel lines, cleaning the carbon off the valve heads, replace the fuel pump, etc... I decided to clean the carburetor and replace the fuel filter, but this did not fix the problem. I took the fuel pump off the carburetor and had no idea what I was doing. I just sprayed carb cleaner in it and put it back on the tractor. Now, there was no fuel getting to the carburetor at all. So, I purchased a fuel pump repair kit and realized the big spring in the fuel pump was missing and likely caused by me not knowing what I was doing. Anyhow, the newly rebuilt fuel pump was delivering fuel to the carburetor with no problem, but the engine speed was still surging. I could see the butterfly choke open and close by the actuation of the governor linkage. At this point I was pretty stumped and my wife was putting doubts in my head about fixing it. Then I started to think that the last tank of gasoline I purchased contained 10% Ethanol in it and realized that the fuel mixture could be running a little lean. I decide to open the air/fuel mixture adjustment out about an 1/8 to a 1/4 turn and the problem stopped. So, I concluded that the problem was related to a lean air/fuel mixture probably caused by the 10% Ethanol gasoline mixture. I was sure I had put 10% Ethanol based gasoline in this tractor before, but the mix may not have been as concentrated, but one thing I am sure about is that my Twin 18 I/C Briggs & Stratton Engine (Model # 400707-1209-01) is running like it should by adjusting the air/fuel mixture. I have not read anything about this type of problem with this engine. There is a note in the manual that recommends not to use gasoline which contains alcohol, but if it is used it should not contain more than 10% Ethanol. (see subsequent fix on Aug 2011)

   
393397 Fuel Pump Kit MAY-2008 7.23
493629 Filter-Fuel MAY-2008 5.59
Front headlight power failed early in life

The front head light system on the tractor is cheap and failed prematurely. I was always having to twist the bulbs and work the wire taps back and forth to make them work. They stopped working altogether around 1993, but I simply did not use them much.  I have considered buying 2 cheap LED flashlights and retrofitting those lights in place of the head lights on my tractor. The tail lights have always worked great. Finally, I took the time to investigate the headlight problem and found some frayed wires at the end of the right head light wire tap that comes from the light switch. The problem is solved and I popped off the front plastic headlight cover and cleaned out a very dirty headlight compartment. The headlights are now working as good as new.

MAY-2008  
Gas Gauge Replacement

This was a cosmetic replacement. The old gas gauge window was cloudy and hard to see the gauge. It did not need replaced, but it was replaced to give the old tractor a new look.

   
951-0226A Gauge - Gas JUN-2010 24.22
Transaxle housing broken after dragging tractor

I learned my lesson about dragging a tractor when the transmission is not shifted out of gear, but I could not get it out of gear. The tractor got hung up after inching into a fire hydrant in the front yard. I could not get it into reverse and the rear drive belt burned in half. Since I had to catch an airplane in 2 short hours, time was limited and I tried to push it to the garage but the wheels kept locking up after a few feet. In my infinite wisdom I decided to drag it to the garage with another tractor. Big mistake! I ended up braking the transaxle housing. Since I found a broker selling off some tractor part inventory I decided to purchase a replacement transaxle at about half the cost of a new one. The 717-1050 transaxle assembly has been replaced with a 753-0539 assembly. It fit perfectly.

AUG - 2011  
754-0281 Variable Speed Belt AUG-2011 15.00
753-0539 Single Speed Transaxle Right Hand AUG-2011 275.00
Engine speed surging up and down in RPM

The engine speed surging problem continued shortly after I thought I had it resolved in 2008 and I just lived with it by pulling on the choke control to keep it running. After replacing the transaxle it was time to revisit the carburetor and give it a thorough cleaning. The idle speed screw (tip was dirty) was replaced with a new one I had from a rebuild kit. I made sure all the jets were clean by holding the spray tube tightly against all ports and verified the liquid came out the other end of the port. There was one jet that was clogged in the float tank and I worked on it until the cleaner was flowing through the other end. I replaced the gasket where the carburetor attaches to the manifold and the one under the air filter assembly. That is all there was to it and the gas is a 10% ethanol mixture. Make sure you clean your carburetor very thoroughly and cleaner shoots out the other end of each port or jet. The idle speed mixture screw was adjusted and now the engine is purring like a kitten at the slowest speed setting instead of stopping and/or surging at higher speeds. The engine surge or speed hunting problem was due to a clogged jet in the carburetor.  The engine runs smooth and the transmission shifts easy between forward, neutral, and reverse. My classic tractor has a second life and should keep the local landfill at least 1 tractor ECO friendly. The engine surge issue has been "nipped in the bud".

AUG-2011  
Battery Failure after 6 years of service (excellent life from Walmart battery)

When I took the old battery to Walmart, I was surprised to discover the battery was 6 years old after wiping off the tag. The new battery turns the starter with no trouble. The battery was replaced with the same part number U1P-7.

   
068113131912 U1P-7 Walmart Battery AUG-2011 28.21
Headlamp sockets intermittent

The light sockets were intermittent from all the twisting the terminals due to a broken wire years ago. Since I have been using my headlights more often I decided to replace the worn light sockets.

   
925-1058A Socket - Headlamp X 2 plus shipping MAR-2012 17.69
Starter drive failure

The starter drive mechanism on top of the starter motor failed. At first I thought the motor was locked up, but the starter drive gear was push up over the gear ring on the flywheel making the motor hard to turn by hand or by the blades with the mower deck engaged. Removal of the engine cover and flywheel reveal the damaged drive starter. I accidentally poured water from another gas can into the tank. After some extended cranking I probably added to the early failure of the starter drive after 22 years of service... Drained the gas tank, carburetor bowl, fuel lines, and replaced the fuel line from the tank up to the filter while I was at it since the old fuel line was getting hard. After replacing the starter drive and the fuel, the engine started with no trouble and continues to purr smoothly. My wife has been pushing me to buy a new tractor the past 2 years, but my old Montgomery Ward (MTD) tractor is still performing well on a weekly basis mowing, mulching, aerating, lawn sweeping, etc...

   
490421 Drive - Starter JUL-2012 20.95
751-10349-72 Hose - Fuel Low Perm 7 JUL-2012 12.35
       
       

 

Mongomery Ward Cross Reference to MTD
Montgomery Ward Model No. MTD Model No.
TMO-33931A 139-693-088
 

 

The TMO-33931A crosses over to the MTD 139-693-088. However, if, you have the original manual for the tractor they simply use the MTD part number which any MTD part supplier should be able to get. I order most of my parts online from Outdoor Distributors (use to be Western Auto) since they are close, but they are very quick with a reasonable price. If you need help they can assist you in the event the part number has changed. Recently, I have seen a few part numbers updated with a new number which makes it a little trickier to find, but there are several other sites I use to find the new part number and they are:
 

          

          

 

If you need to find a Montgomery Ward cross reference number to the MTD model number, you can find it on the MTD web site. This link should help you find the model cross reference numbers:

 

If you need to find an owners guide and suppliment sheet for your TMO-33931A it is on the MTD website. It is not easy to find as it is obscured under the Yardman branded equipment.

 


 

 


 

This page was last updated on 21-Aug-2013