It is currently Fri Mar 29, 2024 4:02 am




Reply to topic  [ 6 posts ] 
 u-joint positioning 
Author Message
MMT Pro Member

Joined: Thu Jan 28, 2016 8:35 pm
Posts: 67
Post u-joint positioning
So I still have my other LT.
MB 35 with M-Carb and pipes.
Over all, I have to say it had been a good motor.
Since I now have my BW 40, I decided to practice my mechanic skills.

Last fall I replaced the magnets and wiring harness. Reset the valve lash.
Motor runs great! I moved on the the drive and I'm currently replacing the yokes and u-joint.
The drive shaft seems to turn smoothly, so I don't think I need to replace the upper and lower bearings. But since I have it apart, I'm playing with doing it any way. How do you know if the bearings need to be replaced?

Back to my question. When positioning the yokes on the engine and drive shaft, are there any words of advise? I find no videos on this and there is no manual with positioning specs.
Do you position the yokes on the drive shaft 1st or the engine 1st?


Wed Oct 10, 2018 7:49 am
Profile
MMT Pro Member

Joined: Thu Jan 28, 2016 8:35 pm
Posts: 67
Post Re: u-joint positioning
So no one has replaced a u-joint that could share their experience with positioning?

What I have seen is that if it is not positioned correctly you rob yourself of power.


Thu Oct 11, 2018 7:43 am
Profile
MMT Pro Member

Joined: Fri Dec 25, 2009 7:09 pm
Posts: 102
Post Re: u-joint positioning
I'll be your huckleberry.

With the shaft all the way in there technically should only be one position where the u joint can go. If you think about it and draw a straight line on both shafts, where they intersect is where your cross section of your u joint should rest. If its too far either way the yokes would not sit square on the shaft and would be in a bind. How this helps. I do like to put my set screws on the opposite sides to sort of balance the joint as a whole. Good luck


Sun Oct 14, 2018 9:01 am
Profile
MMT 1000 Club

Joined: Mon Dec 31, 2012 11:07 pm
Posts: 4820
Location: West Monroe, LA
Post Re: u-joint positioning
I would put the yoke on the prop shaft first, because you can always unbolt the engine if needed to get that yoke on. Been 12 years since we've done it, but don't figure there would be a huge issue doing it that way if you couldn't get it wedged in otherwise.

#CFFITR
#TheGhostBoat
#whoneedsphysicsihaveamudmotor


Sun Oct 14, 2018 10:39 am
Profile
MMT Pro Member

Joined: Tue Sep 16, 2014 6:36 pm
Posts: 108
Location: Sunrise, FL
Post Re: u-joint positioning
Make sure to mark everything after you tighten it down and do short test runs to make sure nothing moves. I've had to drill holes into the prop shaft and motor shaft to have a solid set because the prop shaft moved itself up and destroyed itself and upper bushings on a gdlt.

Sent from my Moto Z (2) using Tapatalk

_________________
1438 Jon / 23hp MBLT


Mon Oct 15, 2018 10:45 am
Profile
MMT Pro Member

Joined: Thu Jan 28, 2016 8:35 pm
Posts: 67
Post Re: u-joint positioning
Just back on here. Thank you for your thoughts.
I did end up putting the yoke on the shaft 1st.
I then swung the motor in place and slid it in together.
Tightened all bolts to secure the motor.
There was still a little play before I set the screws, so I tapped the shaft up so the yokes were snug.

I did make the key way a little longer on both, especially the motor shaft.
My issue before was that it was tight on the shaft, but sliding up on the motor.
I reconnected all wires and the motor turned over.
I'll be getting some new gas and fuel line in the morning and will let it run.
I'll then re-set the screws with some semi permanent loctite.
I'll let you know how it goes.


Sat Oct 20, 2018 8:30 pm
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 6 posts ] 

Who is online

Users browsing this forum: No registered users and 112 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to: