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jeeperguy21
October 19th, 2017, 21:51
I am about to dive into the process of rotating the axle C's to get a better caster angle. Prior to making any adjustments, I measured the current angle on both the driver and passenger sides and am getting different measurements. The passenger side shows 1.1 degrees and the driver side shows 2.3 degrees, shown in the links below:

https://www.dropbox.com/s/0ldsdayjsd4mr0j/2017-10-18%2020.27.50.jpg?dl=0

https://www.dropbox.com/s/3cyuq4oxwpb1mcx/2017-10-18%2020.27.04.jpg?dl=0

Couple of questions:
1) Am I measuring this correctly?
2) Should I try adjusting the control arms to have the caster match on both sides before I start grinding away?

Tim_MN
October 20th, 2017, 08:38
Are you measuring from a raw casting surface, or from a machined surface ? I would be rough measuring caster from the top of the ball joint, or better yet, with the outer C and ball joint removed, measure from the flat machined surface at the ball joint opening. Some variation in caster is certainly possible.

I would be setting the caster angle in only relation to the axle housing, and not in relation to the control arms or the Jeep.

If you are using short control arms, minor caster adjustments can be made with caster shims on the frame side of the control arm.

jeeperguy21
October 20th, 2017, 08:56
I was measuring from the surface right next to the top of the lower ball joint. As I was trying to figure out the best place to measure the caster, I also got a measurement from on top of the top ball joint, which had the passenger caster at 1.8 degrees. I don't recall what it was on the driver side as I didn't snap a pic. Here's a pic of the passenger side:

https://www.dropbox.com/s/cpodda8913kuoj9/2017-10-18%2020.23.49.jpg?dl=0

Since some variation in caster is possible, should I make it the same on both sides before I adjust it, or just proceed and make them the same afterwards? I have long control arms that are easily adjustable. I would just need to decide if I should make the top shorter or the bottom longer on one side during the adjustment.

Tim_MN
October 20th, 2017, 10:05
Since you are going to change the caster, the current measured caster numbers, nor any side to side variance, do not matter, they are only used as a reference. Measure, or assume that the frame side mounts are equal distance from the axle, then make sure the adjustable control arms are close to each other in length, and get to work.

Rotate the C's in relation to the axle housing.

jeeperguy21
October 20th, 2017, 10:12
Sounds good. I plan on rotating both sides so that they are at 8 degrees. I'll make sure the arms are the same length on both sides and then go for it.

Not looking forward to this project, but I'm looking forward to the end result.

jeeperguy21
November 22nd, 2017, 09:46
I started grinding away on the welds holding the axle C's on the driver's side. I must not have enough of the weld ground away because I can't get it to rotate with a BFH. I don't want to grind too much into the axle tube, so I'm looking for a second opinion on where I need to focus my grinding efforts. Here are some pics:

https://www.dropbox.com/s/3ig0sl5qz4ylb3s/2017-11-18%2018.56.40.jpg?dl=0

https://www.dropbox.com/s/ue6egaz7ysahcgz/2017-11-18%2018.53.34.jpg?dl=0

https://www.dropbox.com/s/b0426lvs50uq130/2017-11-18%2018.53.47.jpg?dl=0

https://www.dropbox.com/s/xae8xyomoeor8n6/2017-11-18%2018.55.39.jpg?dl=0

https://www.dropbox.com/s/qoxy4hhzys3t1nt/2017-11-18%2018.55.55.jpg?dl=0

XJEEPER
December 4th, 2017, 15:27
I PMed you the link to my knuckle rotation thread, but I'll share it here as well. Too bad Photobucket killed my picture links, but there are good descriptions of each step, which should help.

http://www.naxja.org/forum/showthread.php?t=935127&highlight=knuckle+rotation&page=4

jeeperguy21
December 4th, 2017, 16:15
I PMed you the link to my knuckle rotation thread, but I'll share it here as well. Too bad Photobucket killed my picture links, but there are good descriptions of each step, which should help.

http://www.naxja.org/forum/showthread.php?t=935127&highlight=knuckle+rotation&page=4

I read the thread in great detail prior to reaching out to you. I was able to see the pics using a Chrome extension that makes them visible. I'm hoping for some advice one where I currently stand. In my opinion, I think I've ground sufficiently, but the C's won't budge. I'm putting quite the mark on them as I've pounded them with a sledge.

I'm wondering if you can see anything obvious in the pics to point me in the right direction. Is it more grinding into the axle tube that I need to do, try to focus my efforts onto the C's themselves, or something else? The last thing I want to do is to grind a hole into the tube by attacking this the wrong way.

donthelegend
December 4th, 2017, 22:31
Did you cut fairly deeply into the inner C or stay farther out (so you were grinding more of the weld rather than the metal of the inner C)? I see a couple spots that look kinda like the end of the weld but it's hard to tell. The best way I can describe it is that it looks like a small "tear" at the transition point. I'm going to try to mark up a couple of your pics and I'll post them in a minute.

Edit:
https://lh3.googleusercontent.com/tlVuUIyxezwES0dlCfeP8tjg9E_-4SCa8l_9HlRcFTnVcTk2gzz8OzMp6iXk6VGsXDL_YQgvCeBWRM R4QXJ9NDleUg3of99s-tbrR4YS-oPkqalvSLsmwtZHEj58czrrm0LVDsrLDCpeIkzA0zvGo6sCQ8p ZymoFmFxHKdkSKDzC56mhMn15ceX5F9NnmV1GOdbM_sfJz67VP ftWn6U6t39w7iFHJuOWFO0qP1tjw4_jAfVzU8V9Dl7KQYZeNl4 _oDrUNn66kzaRN_5lqyJxq_umaHxPNz16pHF37ITBVJmlChLMF TVUdqFw-p5NOxUTppXLUqM5XfKfbPn5qdK95SPilWQktN5Funha-KkdSbzt2xYb7wyGibpJS1sZ7gAulyhcVTUx9-KQKuyx9yXDY_f3rTGy0GiIjIOujh9e7zoie3Dbqcq8JVYxCzt7 mAigVLeJrh-i60B_bHw_P53PjjZvs1RZeSD42bNCPeGQsFM5xff39KRw7jWpb VJ2pXwWJ8HabIClZ1W1foCq_YID08CLNF5yOKhGyu02ig1JY81 yNae6HNI5-k-mK3kpkSa4A63svH1-CCxynismg8nU-turCsL16ScQNdtmAQFJjw=w688-h917-no

https://lh3.googleusercontent.com/yFdFqHSZf1wKoQKb5z_Z0dv0YVu4culS6HGiAz2y1h-mz0CQFLMw5SYjE7tXVY8EaOnzNZOX8HAbXXah9Z1XWAK6nOGh4 0VyNzS9pz5pvLcnxcxzsj1YU4HcFFS8UlWMX7MLlRwiBD5jYY0 aho4c4dOVz_qtk0gtYaUZvhzpLaez1iU0b37GiFcLO2SNFt2Ya 1mrxE53-UbCXcO27dRFfc57T5pUN4F_9u863wyPqCLXmzUDuowrSYWdHhf 9p3T4EY7v5vOVKCPIOU1-DAJiRIVm4gSYMtAhoDWfK1R6An0sJ0KgdmgYZCT6Glq5hYUHrq LFlrRzH3Qz0Gf-sfuQWBkj9Ua6SGmAgMiptg1h70fJdYr-rL5btGTmXi1g3f8QPj90YIf4yAxvcHVMZ3jebRPaPdb4mwItKp cSQ-TDUOPKWisLUi58gzWz1ybkJG6pgw1eU_jmlLl22xVP7Wc_b4RR qD4kgZ2zmIj6l16PKalhng0DGVnj7veXWWNO8zzO6J7g3wGBOu rD3hP7oo3vKptXrp_EdXjxE9n_qzl0yJ9i6NsY4CGlX4BHWNjp A3Hm9vPWsrl5X4MBWHn5_kIT3XqcyLVoMtvJ7ta9aS6LZg=w68 8-h917-no

XJEEPER
December 5th, 2017, 10:16
I read the thread in great detail prior to reaching out to you. I was able to see the pics using a Chrome extension that makes them visible. I'm hoping for some advice one where I currently stand. In my opinion, I think I've ground sufficiently, but the C's won't budge. I'm putting quite the mark on them as I've pounded them with a sledge.

I'm wondering if you can see anything obvious in the pics to point me in the right direction. Is it more grinding into the axle tube that I need to do, try to focus my efforts onto the C's themselves, or something else? The last thing I want to do is to grind a hole into the tube by attacking this the wrong way.

It's difficult to tell from your images, if you have removed enough of the weld/knuckle to allow the knuckle to rotate freely on the tube, but suffice to say that if the knuckle is not rotating with the application of force from your hammer, then you need to remove more material.

It appears to me from the image 18.55.39, that you haven't sliced into the lower-rear section of the knuckle enough to cut through the weld.

I recall shaving about 1/8"+ from the inner knuckle surface, in order to get behind the factory weld. This required several cutoff discs and a right-angle die grinder to accomplish.

http://i173.photobucket.com/albums/w52/XJEEPER1/XJ%20Build%20III/100_2964.jpg

A small section of weld will prevent the entire knuckle from rotating.

jeeperguy21
December 5th, 2017, 10:42
Thanks for looking at the pics, guys. I now think that I attacked the weld much more so than the inner C. I don't believe I really got into the inner C much, which is likely what is causing my inability to free it from the axle tube.

Next time I have a chance to grind, I will focus most, if not all of my efforts on shaving down the inner C to try and free it up. I'll let you know what the outcome is.