Good Morning All

I have a problem with the snap rings on the left drive wheel, but I am not experienced enough to figure out what the solution is. If I have violated a rule of posting, please forgive and correct me; I am new at posting questions.

My 14SB, after 20 years of fine service, failed to self-propel while it was in use. The drive wheels began to lock-up intermittently. After cooling, the self-propel feature worked again for about 20 minutes and again the wheels locked up.

I disassembled the drive wheel assembly and found that the left wheel arm roller bearing had become a powdery disaster similar to what one might expect from having forgotten that the grease fitting had a purpose.

I carefully reassembled the drive wheel assemblies minus the remainder of the bearing to allow me to determine if the transmission was still functional. Fortunately, it appeared to work well.

My problem with the snap rings became quite evident when the right wheel began to separate from the mower housing. Both snap rings in the left wheel assembly were seated in their grooves quite well, however the right wheel separated from the housing after about 20 feet of travel. The snap rings in the left wheel had both climbed out of the groves. The outer snap ring and the gear had fallen off the shaft and the other snap ring and washers had moved about an inch toward the end of the shaft.

I repeated the reassembly, operation, failure sequence three times. I have no idea what I am doing wrong here. There seems to be no problem with the right side snap rings. I have used snap-ring pliers to remove and replace the rings. Can anyone please suggest what I am doing wrong?

Thank you
Stan

Hi,
I am posting a picture of the 14SB rear wheels and components. I fail to understand what you are referring to. The wheel are bolted on. The rear wheels have a large black spur gear attached to the inside of it. It is driven by a smaller pinion that is on the tranaxle shaft. It is the pinion that is held in place by snap rings
Deformed snap rings will not stay in the grooves and will ride out. Also, beieve it or not, snap rings have two none identical sides because of the manufacturing process. The snap ring begins life a s part of a sheet of steel and a press stamps it out. It is heat-treated after the stamping. As a result of the stamping process, one side has a very slightly rounded profile while the other has a sharp edge. Carefully feel them with your fingertip to verify. The snap ring will have better holding performance with the sharp edge in the direction where better holding is needed, outwards in this case.
The number #18 parts are snap ring in the picture. I have worked on many a 14SB, but try to clarify your question, please.
Peace,
Clarke

Good Morning Mr. Crigby

Thank you for the tip. Those many years of valuable experience are obvious from your answer.

In answer to your question: It isn't just the wheel which separates. When the snap rings fail, the left wheel remains attached to item 4. Item 4 and all the washers, snap rings, pinion, and wheel move together toward the end of the axle. The pinion (20), outer snap ring (18), and the tiny key (24) from the axle fall inside the wheel housing trapped between item 23 and the wheel. The inner snap ring is then out of the groove and is on the shaft.

The axle and transmission are then free to move within the mower deck toward the right wheel (I am making the assumption here that nothing else keeps the transmission from moving sideways). The right wheel assembly moves away from the deck. When the entire right wheel assembly has moved outwards about an inch, it loses its support from the mower deck, and allows the mower right corner to fall to the ground.

I have now closely examined the snap rings: the thickness of the ring is uniform at all places. The width of the ring puzzles me a bit however. At the portion of the ring equidistant from the two ends, the width measures .090 inches. The two ends however are not as wide, measuring .055 and .060 inches. Is this normal or am I seeing 20 years of wear?

The comment about heat treatment may be golden! I am sure when the bearing failed, it got warm. There is the question of did it get hot enough to modify the heat treatment characteristics of the snap ring

I am heading to my neighborhood JD dealer for some parts. Thank you for the assistance. I will tell you of the result if they have the parts.

Stan

Hi,
The snap ring shoule be symmetrical, ought to be shiny from wear. How well did the axle on that side survive, the one in the transaxle?
If it survived withou being grooved from the needle bearings, you are indeed fortunate. I will attach the parts key, and give you the Deere link.
Operator's Manuals for John Deere Equipment (http://www.deere.com/en_US/homeowners/services_support/manuals.html)
Bookmark this if you want; once you click the parts catalog link, if you bookmark it you will be asked for a User name and Password - this site is shared with the public, but it is also a site that the dealers use.
Peace,
Clarke

Good evening Mr. Crigby

I was fortunate enough to obtain two replacement snap rings this afternoon, however they did not cure the problem. The new ones behaved just as the old ones had.

The axle shaft survived quite well. I fortunately caught the problem just as it began and damage to the shaft was minor.

Unfortunately, my problem still exists. I am starting to believe something is causing the transaxle assembly to move to the right side. In the many times that the problem has occurred, it has always been to the same wheel in the same fashion. I am puzzled why there is no randomness as the right and left side are mirror images of each other.

Thank you for the parts list; I will need to order a bearing if I can solve the current problem.

Stan

Hi,
At the dealer I worked at for some time, the acceptable repair would involve the replacement of #4. I would say you have a problem there.
I am sorry that this drawing is so bad. The dealer I worked for no longer exists, or I could "borrow" a user name and password. I will ask around to see if I can find someone I know at a Deere dealer. There is some "stuff" that authorized access can get to that cannot be arrived at by stealth, like the parts breakdowns. A serial number can be looked up for over 45 years back, for instance.
Peace,
Clarke