I see there are several questions about U Joints, so I thought I would throw mine in also. Hopefully someone has seen this before.

I have seen various mud motors (longtails) that have a regular u joint between the engine and the drive shaft. I have also seen some motors with a 3 piece u joint, consisting of 2 "cross pieces" and some type of extension that looks like an "H" between the cross pieces. I saw one of these on a motor recently and saw the part # as 1502 S 1.

What is the purpose of the 3 piece u joint? Is this a custom part? I have looked at our local farm store and can't seem to find one. I also searched the net for the part # but can't seem to find it.

Any help from the MM Forum on this?

TIA

As I understand it the reason for the H piece is to reduce the shaft angle at the U joint and make it a more gradual angle. The more angle you have on a shaft, the more power you lose. Most longtails are on a 13-15 degree angle, and having the H piece would make the angle a bit more gradual. Also it lets the motor stay more on the horizontal. I'm not sure that it's really necessary, as most longtails with a regular U joint seem to work fine, but there could be some benefit to it. The only longtail that I've seen with an H piece is from Utah Marsh Motors, is that what you saw?

I actually own a Utah Marsh Motors small hp frame and it has the same joint. The one I just saw was what looked to be a 31 hp Kohler. There was no name on the engine or frame. If it was home built it was nicely done.

Still trying to find out where to get this 3 piece u joint.

Thanks

How do you like your UMM longtail? I've been looking pretty hard at them, they look like solid units. You could always call Mark from UMM up and ask him where he gets his H piece, I'm sure he could tell you all about them.

Pumpgunner: Sorry, been busy and must have missed your post. Sadly, I haven't run my UMM. I bought it for a couple places, and to go on my Gheenoe. Then for the next 2-3 years, I was able to hunt elsewhere. Just didn't need it. It sat in the back of my garage. I got it assembled this past weekend with a 5 hp Honda motor, but didn't have time to get it wet.

I did, however, get a chance to look it over while installing the engine. I can say that it showed great engineering and the workmanship was excellent. Even my buddy that is a certified welder noticed the quality of the welds. I would not hesitate to buy a finished motor from Mark.

I have communicated with Mark on a couple of occasions. He has always been extremely helpful, and always ready to answer my questions, and has in fact answered my questions. I just don't want to bother him much as I know this is a busy season for him, and I don't want to take advantage of his generosity.

That a CV or double cardan joint, they help with the joint vibration at higher angles (15* is about the max for a normal joint) and they last longer as the angle is split between 2 joints. They are more expensive and if they fail it tends to be a little more spectacular to watch as that center piece can sling out of there pretty hard.

Climb under the front of a lot of newer Jeeps and this is what will be on the front driveshaft (solid axle cherokees for sure)

Thanks Ironman. I think I understand it now, but I still can't find one. Everywhere I look at u-joints, it doesn't seem like they have them. I must be looking for the wrong thing. Anyone have a part# and manufacturer or supplier?

Thanks

mudde

Contact motion industries in eau claire wi they should be able to get and have great prices

thanks Mallardman!

if they cant seem to find it let me know