Knuckle bearings Replace

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Imtractotor
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Knuckle bearings Replace

Postby Imtractotor » Tue Jun 16, 2020 3:34 am

Im new so go easy
I have a YM 165d tractor. Its brilliant but front drive keep giving trouble and as I have grass wheels on back so its useless without front wheel drive. Theres no leaks and I keep it well oiled. The thrust bearings and roller(needle) bearings get crunched. Last time I had it done professionally but it didn’t last longer than when I did it myself(< 10 hours of 4WD use). I’m convinced the backlash adjustment is not being done correctly. I have the service manual but it doesn’t describe how it should be done other than to use shims to adjust backlash. I use generic bearings and Im sure the service engineering company did too. Is that the problem ?
Im going to try this again myself but would appreciate any help. Please

Aaron
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Re: Knuckle bearings Replace

Postby Aaron » Tue Jun 16, 2020 1:03 pm

Backlash is important but I wouldn't think the backlash would cause the needle bearings to fail. Are you sure your front & rear tire ratios are correct? Mismatched tires can put an enormous strain on the 4wd - especially if used at high speed or on a surface with good traction.

winston
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Re: Knuckle bearings Replace

Postby winston » Tue Jun 16, 2020 2:28 pm

Are you making sure you do have a tad of backlash when you put it together. If so, I wouldn't think backlash is causing your bearing eating problem. If no backlash then it might be your problem.

Don't know just what manual you have but the 135/155 service manual does have instructions. I think the 155 is close to the 165 although not sure.

Imtractotor
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Re: Knuckle bearings Replace

Postby Imtractotor » Wed Jun 17, 2020 7:55 am

Thank you both for reply. This is very very helpful information and which I hadnt considered as a cause of problem :roll: . @Aaron my tryes are 8-16 grass and 6.00-12 agri . I use a small grubber with 7 tines that go 8-10 inches into soil and its when using this that I first notice the problem and first time I had problem was when I bought new tyres for front.
What should the ratio be ? or is it wrong to have a mix of agri and grass tyres. What size agri tyres should I put on back ? Wheel diameters are Back 30.5" and 22.5" on front, what should I change to ?
As part of my repair can I ask if there are different grades of bearings that I should use or is it ok to use generic.
Really glad I joined up here.

Aaron
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Location: Iowa Park, TX

Re: Knuckle bearings Replace

Postby Aaron » Wed Jun 17, 2020 8:21 am

It left the factory with 8.3-16 rear and 6-12 front. I dont find a lot of info on the 8.3-16 but it looks like a diameter of 32". I dont see the rolling circumference published anywhere so that will limit how close we can get with our numbers. The 6-12 is 22.7" diameter. 32"/22.5" x 30.5/X says the rear should be 31.7". A little over 1" difference in diameter does not seem like a lot but that tire will be going about 4 inches farther every revolution than the front tire which would add quite a lot of stress. Of course you can also change that rolling circumference by just adjusting air pressure also.

I did those figures all pretty quickly and before I had my coffee so there is no guarantee they are completely accurate :).

I would think that as long as you used a name brand bearing you should be fine. I know some people have also replaced the needle bearings with brass bushings and seems to work fine.

Imtractotor
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Re: Knuckle bearings Replace

Postby Imtractotor » Thu Jun 18, 2020 2:18 am

:D @Aaron much appreciated. The discrepancy may be due to age of tyre and/or air pressure of present tyre as I didnt check that. I will start my search for agri tyre 8.3-16 today and start pulling gears apart for a rebuild. No doubt more later but I may be on right track this time


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