Rotating Ring Gear

Bill, Ike and Jim: I can see where items 1 and 3 are necessary if the engine slides forward to give working room between engine and torque tube. And it may be that it can be done in that manner. However, I have a xerox copy of a second Massey-Harris Pony manual which gives a word description plus a picture of method of removing clutch. While I don't have a copy of the front cover, I believe it to be an official Massey-Harris publication. The last page shows a Massey-Harris symbol, Massey-Harris Company Limited, Established 1847. The following info is found near the bottom of the page "5479 Jan 2-51 Printed in Canada". I won't go through all of the items to be disconnected in preparation for the split but the grille and radiator are not mentioned. Word description includes the following: Hang engine (forward) half of tractor in hoist. Block up rear half of tractor by installing a rolling floor jack under torque tube. Take out bolts and cap screws which attach torque tube to engine and front frame. Separate tractor halves enough to permit removal of clutch from flywheel. A picture shows a Pony separated at junction of engine and torque tube as is common in Cubs. I now think that I need to do more research before attempting a split. I appreciate the input from each of you and hope that additional comments will be provided. There must be forum members who have been involved in removal of the clutch from a Pony and I certainly want to hear from you. It may be that both methods are acceptable for a Pony. If so, I think that I will probably slide the engine forward and not have to split it. Thanks, Dan
 
I have worked on larger 20-23 series MH tractors but not a Pony. My experience was those tractors didn't need to be split (the frame rails unbolted from the transmission case) but the engine slid forward and removed in order to do any meaningful repairs on the clutch assembly and flywheel. Even if the radiator and fan assembly removed, the hydraulic tank mounted in front of the radiator was still in the way..
 
Dan, I did not make myself clear, my intention was for you to look at the wear marks on the teeth, to see how deep the teeth were going into the ring gear. If they are only going in a little way, you need to see why, and solve that.
 
I have had time to examine a third service manual for the Pony, this one by Jensales. They aren't in agreement on how to gain access to the clutch and flywheel. Having the benefit of information which you provided allows me to better understand their instructions. The first one (MH-49) recommends sliding the engine forward, the second (MH-51 I think) recommends splitting at the torque tube-engine juncture, while the third (Pony Service by Jensales) explains both approaches. I have taken a new look at the Pony with the two approaches in mind and think that sliding the engine forward will be the easier and safer method. It has a manual lift only so no hydraulic unit to limit forward movement. I hope to get started tomorrow. John: I will be in touch by e-mail tomorrow and will probably send a picture of tooth wear on the Bendix. Again, thanks to each of you who have responded. I continue to be interested in your comments. Dan
 
The following info is taken from the manual "Massey-Harris Pony Tractor Operating and Servicing Instructions" (1949) by Massey-Harris Co.
TO REMOVE THE CLUTCH
1. Drain the cooling system
2. Remove engine sheet metal
3. Remove radiator grille and radiator
4. Disconnect throttle and choke controls, gasoline and oil pressure lines, and ignition cable from engine
5. Remove engine mounting bolts
6. Move engine ahead sufficiently to clear main drive shaft from clutch
7. Remove screws holding clutch assembly to flywheel

Yesterday I started the process which would lead to removal of ring gear and flywheel. I encountered no problem until I reached item 6 of the list. I moved the engine forward until the front of the oil pan butted against a crossmember of the chasis and that was as far forward as it would go. And that wasn't far enough forward to allow easy removal of clutch and flywheel. So, the oil pan had to go. With all bolts removed and the pan lowered, there was insufficient space between the radius rods (the rear portion of the rods are held in place by the front axle pivot pin) and the bottom of the block to slide the pan out. Well, back to the manuals again to check on procedure for oil pan removal and this is what I found. "Removal of pan is complicated in early production models by the front axle pivot pin and the tractor must be blocked up under forward end of torque tube and pivot pin removed before pan can be lowered". I completed that step and think that I am now ready to remove the clutch, flywheel and ring gear today. For those having early model Ponys, I would add the following:
8. Remove front axle pivot pin allowing radius rods to be lowered. Support front of torque tube before removing pivot pin.
9. Drop oil pan
Completing steps 8 and 9 allow the engine to be moved forward a sufficient distance to gain access to the clutch and flywheel. Perhaps Pony owners will know an easier method of accessing the flywheel. I welcome your comments. Dan
 
I'm thinking back to something I had to do with an automotive oil pan at one time. The only way to remove/install the oil pan, without lifting the engine off the motor mounts, was to rotate the crankshaft. That allowed me to thread the pan out as each throw/counterweight rotated up and created the necessary clearance above the frame crossmember. I thought of it as "unscrewing" the oil pan via the crankshaft.

It sounds like similar architecture used with the smaller Pony tractor as with the 20 series I'm familiar with. Completely removing the engine from the tractor was the easiest and quickest way to replace the clutch and pressure plate. While you have it apart, now is a good time to service the universal joints on the torque shaft if the Pony has them.
 
I removed the clutch and flywheel today. After cleaning the circumference of the flywheel with carb cleaner, I then applied a very light coat of 3-in-1 oil. I marked the flywheel, front and back, in the two areas of worn ring gear teeth. I was then able to gently tap the ring gear off from the flywheel. Since it came off easily, I decided to see if I could put it back on the flywheel. After rotating the gear, I placed it on the lip of the flywheel and began tapping and was able to seat the gear back in its original position. Finally, I sprayed a liberal amount of carb cleaner on the flywheel-ring gear junction and wiped it good to remove any oil which remained. Now my question. From what I have read, the gear usually must be heated to replace it on the flywheel. Should I anticipate any problems (slippage) as I was able to replace the ring gear without heat? Carl, I was excited to learn that I would not have to split the tractor . However, sliding the engine forward was more involved than I had anticipated. Since the radiator was drained and removed, I was able to correct some problems there. But I don't know which approach I will use if I ever have to do this job again. I guess that I will start putting it back together tomorrow. Dan
 
Dan,

Looks like you are making good progress on your Ring gear Job. I would not anticipate any problems with ring gear slippage, as I have also tapped ring gears off and on again.

The fit of flywheel to ring gear is semi-press fit, if you did apply heat the ring gear would literaly fall on (or off) the flywheel and tighten up once it cooled down. Applying heat is faster and easier thats all.

Good Luck

Mark
 
No oil pan gasket available for the Pony locally. I purchased a sheet of gasket material and will make one today. A question on ring gear wear. As predicted, the gear had worn teeth at two locations which were 180 degrees apart. I understand, when the motor ceases to fire, that each compression stroke acts as a brake to slow, then stop the crank from turning. My jumbled thinking says that there should be four areas of wear on the teeth, one for each of the four compression strokes. Why only two? Thanks, Dan
 
Kind of sleepy, so not sure this will make since to you, but piston only fires every other round, and if you look at crank throws, they are 2 up and 2 down, so only 2 places where the engine stops.
 
One cylinder fires every 180 degrees of crankshaft rotation. So for each piston, there is another one that fires exactly 360 degrees later (back to the same crankshaft orientaiton). Either of those two pistons coming up on compression would stop the crankshaft in the same position. The other two cylinders would tend to stop the crankshaft 180 degrees away.
 
Chemotherapy treatments tend to sap my energy level for a few days and that has been true following the most recent session. However, I am feeling almost human today and want to get back on the Pony project. Both the clutch and flywheel have been removed, I have rotated the ring gear on the flywheel, have ordered a tool to align the splines and it should arrive tomorrow. I had hoped to bolt the clutch to the flywheel then install the combined unit on the engine. But it now appears that I must first bolt the flywheel to the engine, then attach and align the clutch unit to the flywheel. Is this the correct sequence? My next question: I removed the clutch from the flywheel and laid it aside. I have made no adjustments of any type to the clutch. Since the clutch functioned properly before removal and since there has been no adjustments during or following removal, I should only need to bolt it back on the flywheel and it should function properly without any adjustment. Is this correct? As always, thanks for your advice. It is appreciated. Dan
 
Dan - I believe you should be OK on your clutch adjustment. However, if you have the specs it will be a good time to double check the adjustment.
Your sequence sounds correct too.
 
Flywheel is mounted first, then the clutch disk and pressure plate. You won't be able to get to the flywheel mounting bolts with the clutch disk in place.

If you can easily access the flywheel and the pressure plate with the engine mounted. Center the disk in the pressure plate on the pilot shaft hole. Do not fully tighten down the pressure plate. Leave just enough tension so that the clutch disk can be moved with a bit of pressure. Mount the engine to the torque tube. When assembled, tighten down the pressure plate. This way you don't need a clutch disk alignment tool.
 
I installed the flywheel and clutch (using an alignment tool) a few days ago. I was able to work the oil pan back in position and get it installed. But when we slide the motor to the torque tube we hit a brick wall about one and one-quarter inch short of bringing the two components together. I have rotated the flywheel slightly many times in an attempt to move that last inch or so but have never gotten past this point. I believe that the problem must be a failure to get the splines of the pressure plate to mesh with those of the drive shaft. We reached a point of frustration and decided to shut down for today. I welcome your suggestions. Dan
 
Dan,

Does it have a pto? If it does, you should be able to engage the pto and use the pto to turn the drive shaft while you are trying to align the drive shaft and clutch.

Ike
 
Ike: It does have a PTO. However, I haven't yet installed the radiator so I have used the crank pulley, as well as turning the flywheel, in my attempts to mesh the splines. I have been thinking about possible reasons why they won't mesh and I may have identified the problem. While I had the motor and torque tube apart, I noticed that the front of the drive shaft set quite low in the tube. I can grasp the drive shaft and move it up and down. I am now thinking that the anterior tip of the drive shaft contacts the clutch below, rather than at the level of the splines of the pressure plate. If so, how can I raise the tip so that it meets the clutch at the proper height to enter the pressure plate? Dan
 
I installed a pulley on the PTO and went that route to match splines. Gives finer degree of control, and it took only a few minutes to put them back together. Now to trace down an electrical problem and when that is solved I should be ready to go. Thanks for advice from each of you. Dan
 
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