Drive shaft pin
 

I have a 127 hydrostatic. Early this fall I bought a new coupler and a used driveshaft that I made sure a new roll pin fit tightly. I'm positive that I haven't put ten hours on the replacement parts.
Tonight the roll pin just fell out while plowing snow. Luckily I found the pin and managed to drive it back in. I was going to wrap a hose clamp around the coupler to make sure it stayed together but didn't have one to fit. Ran it about ten minutes and it did it again leaving me sit in the middle of the road as I turned around.
I am at a loss as to why this is happening because I had to use a hammer and drift to drive the pin back in. The new coupler is made of steel instead of aluminum like the old one and I am thinking about putting a tack weld on the pin and coupler to keep it all together.
Does anyone have any advise on this recurring problem???

I think your driveshaft is the culprit. Probably worn just enough the pin won't stay in.

I'd try a little Loctite . someday you might have to take it apart again

Use the universal tool, duct tape, BTDT

If you are referring to the pin in the front of the shaft, it is a (solid) steel dowel type pin, a spiral pin will only last a few minutes in there and a roll pin won't last very long either.

If the hole is enlarged I have taken the shaft out and smacked the hole with a hammer on one side and then drove a new pin in from the other side. It's still in there (I guess, it still drives).

If you are talking about the pin in the rear flange on the transmission input shaft, then my best guess would be a heavy duty spiral pin.

I've never seen an aluminum coupler.

I'm listening to Yosemite Sam and I agree. Roll pin, Spiral (Spirol) pin and dowel pin are three different pins. No-no to roll pin.

I grabbed the listing for the driveshafts I make.


The flange end is turned and is part of the driveshaft. The engine end uses a solid pin that should be an interference fit.

The pin is the front one and is solid. I had to use a hammer and a drift to put the pin in the driveshaft when I installed it this past fall.
I used a hose clamp before and will probably go that route again.

Yeah, this setup seems really short lived. I'm thinking of going to a rag joint.

I don't know about the life of a rag joint either. I have had to replace a few of them on some of my Ford cars and that is an easy slow turn and not subject to the high rpm's and sudden jolting that these pins are subjected to.

I've worked on many cubs that still had the original pin, and the same goes for the rag joints. I'd say 40+ years is a pretty good test of time. If your pin keeps falling out, I'd say that it's time to replace the shaft. Or, like Don said, put some loc-tite on it. Both types of drives are fine, they don't need to be "switched over", just repaired. Take a few minutes, spend a few dollars and it will last another 40 years.

I dunno Jon-I replaced the driveshaft and pin in November and had the coupler machined on my 129, and it is already loose after about 3 hrs run time. I expected 40 more yrs, but don't think it will happen. I'm looking hard at some other solution like the rag joint on Quietlines.

This is what I did on my 149. It's part of a 2000 series, the hub bolts to the same place on the engine as your existing drive plate. The tube just slips over your existing drive shaft and then you drill it and put a spirol pin in it. Also makes it easy to remove the shaft if you need to replace the rag joint at the pump.

That looks like a good solution there, Sam.

That is odd..... It should have lasted longer. Perhaps you have another issue that is putting too much strain on the pin? :bigthink:

My buddy Chris has a 169. We replaced the driveshaft in it and the pin also..... I think he mentioned the other day that he was still having issues also. We haven't looked into it yet.... and my memory is not great, so I don't remember details. He will be in here today as I'm working on one of his trucks. I'll ask him.

That's pretty slick indeed :)

Sam Mac, When I redid my 149 I went with the rag joints at both ends, but I really like your mod and trying to get the facts in case I ever do another. So some questions if you don't mind....

Since you said a 2000 series I just randomly pulled up a diagram of a 2130. So are you saying the drive shaft here (part #1) is hollow and the i.d. is the same as the o.d. of the 149 (5/8" I think), and you just cut the motor end off of the 2XXX shaft, Correct?? How long is the 2XXX piece and is anything cut off the 149 shaft?? Any machining involved?? Thanks in advance.

The ID is 5/8" so all I did was put the shaft in my chop saw and cut it about 8'' from the end. Bolt the hub the engine (bolt pattern is the same) Cut the damage part of the OEM shaft off. Slip the 2000 section over the 149 shaft, assemble it to get the finished length, mark it. Remove the shaft drill it and pin it. Put it back in the tractor. Sounds more complicated than it is. You'll need a complete shaft for a 2000 series. Doesn't matter they only thing different is length and your going to be cutting it anyway. One shaft is enough to do 2 tractors. Try the sponsors at the top for the shaft.

Looks like both ends of the 2000 series shaft are the same.
Thus you can cut it and use it on two tractors?

Is there some polyurethane rod pieces in the bolt on hub that absorbs shock loads or slight misalignment ?

I think the flywheel cup is aluminum but the actual coupler is steel, at least the one i have on my 129 and the pin isn't a dowel pin or a roll pin its a spiral pin!!

Yep you end up with enough for 2 tractors. The ends have 8 blue plastic "barrels" that fit inside the hub that bolts to the engine. Some misalignment is OK but try to keep the shaft as straight as possible. Tip I learned is to use grease to hold the barrels in place while you insert the shaft into the hub. Here are some pics of the parts.

OK, now I understand. So in addition to a drive shaft I would also need the a hub and the "barrels". Thanks again.

Yep but it's all part of the drive shaft. They are fairly inexpensive if you buy them used. Just tell who ever you are getting it from that they need to make sure both hubs and all 16 plastic barrels come with it. The used tractor parts guys don't have a big market for these things because they just don't go bad very often.

Talk about timing, I was perusing my local C.L. this morning and ta-daa, this guy is dismantling a 2130 about 12 miles away. I contacted him about the shaft, hubs, and barrels and he said "come and get it for $20" and I did (plus some other junk). I have a 105 that needs the hydro fan replaced so I'm just gonna do this mod too. Thanks again Sam Mac for all the info.

I've been searching the forum for something like this, to upgrade, repair my 149. Thanks, for the information and pics.

Here's what I did on my 149... in case you are looking for a rag joint solution.

Yep hard to beat $20.00 for the parts. I've also used 2000 series front wheels but you have to cut the hubs down 3/4" on one side and 1/4" on the other to fit the spindles for a narrow frame. 1st pic is before cutting 2nd pic shows the wheels on my 71/121.

I really like that, gotta do me one in red one of these days. How did you cut down the wheel hubs, (lathe?).

The guy still had the wheels and axle, I wondered if the front axle and spindles were considered supersteer parts. Would you know?? (it was a 2130)

Actually they did the wheels in a Bridgeport. They said the rims were out of round so it was faster in the milling machine. 2130 front axle is not a Super Steer and it won't fit the older tractors. I send them to the scrap yard.

I used a Quiet Line drive shaft like the one in Sawdustdad picture.

Rear drive shaft roll pin
 

Sheared my rear roll pan last night on my 782. Was curious if anyone knew what size the replacement roll pin is. There is nothing left of my existing one to get a good measurement. Thanks in advance.

Cub says 1/4" X 1" ( 715-3000 PIN-SPRING 1/4 X 1 )

You can buy them from McMaster Carr for less. I listed both the 1" and 1-1/2" long versions.

http://www.mcmaster.com/#catalog/121/3339/=wkfaiu

1" 95755A404

1 1/2" 95755A419

I'm having trouble getting the spiral pins out of my drive shaft what's the trick

A model number of your tractor could help out some,

I grind the pin so it is flush with the side of the shaft/coupling, if the shaft is still in the tractor I use a spiral pin punch with a long adapter that I made and a two or three pound hammer. Make sure that you back up whatever you are hitting on to avoid damage to shaft/bearings/seals.

If the shaft is out of the tractor be sure that it is laying on something very solid, use the same technique as above.

It is possible that the pin is sheared and the shaft has turned inside the coupling, if this is the case you will NEVER get it beat out until the holes are all lined up.

Good luck, they can be a pain.