Knuckle Rebuild Help (1 Viewer)

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Joined
Aug 23, 2005
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Location
Magnolia, TX
I'm in the middle of a front disc brake swap and knuckle rebuild using FJ60 knuckle assembly on a 70 FJ40 axle. I've swapped birfs onto my inner axles, set the preload of the knuckle, which comes out to a little under 5 lbs using a fish scale. The problem I'm having is when I attach my dust cover and new gold seal on top of my spindle, my knuckle become VERY hard to turn. It happens once I start torquing my bolts down on my gold seal to secure the dust cover to the spindle and spindle to the knuckle. Any thoughts. I'm :bang: :bang: right now trying to figure out why I have so much pressure on my knuckle. Here is a picture I shamlessly stole from 1973Guppie's front disc swap rebuild which I have been following.

attachment.php
 
Did you grind the inside of the knuckle ball to clear the larger birfs?

my guess is interference between the knuckle ball and the birf.
 
Did you grind the inside of the knuckle ball to clear the larger birfs?

my guess is interference between the knuckle ball and the birf.

I did but I'm looking at it and I may not have ground enough of it. I notice that when I just attach my spindle and turn my knuckle and end of the birf that sticks out of the spindle is moving. So if I turn my knuckle to the right, the birf end will move and contact the 9 oclock position on the spindle and vise versa when turning left.

So would this mean I need to grind down more of the top and bottle as well as the left and right side of the knuckle ball?
 
did you take the birf apart?

Its normal for the birf to move a bit in the end of the spindle.

I did take it apart.

I think I've narrowed my problem to 2 things. When I reassembled my birf I did a martack at the end of my axle. I did it at the 1 3/8" to 1 1/2" from the end of the axle as required. With that said, I don't know if that martack is causing my birf to not seat all the way into the axle housing. I think this is my main problem. Secondly I may have not ground out enough of the bottle of the knuckle ball to give the birf enough room inside.

Thoughts?

Nick
 
Yeah-Why did you bother with a Martack? It's totally unneeded. Just run the snap ring. How hard is it to remove 1 snap ring?

I would go in there, grind out the martack and assemble properly.
 
I just completed the same mod to my 73.
Is your spindle fitting into the rescess on the knuckle correctly ?

Loosely install the spindle bolts and check after tightening them 1 at a time.

If you have any issue with increased force needed to turn the knuckle after installing the spindle bolts it woudl be a good indicator of what the issue is.

I have heard of incorrectly done Martacks causing issues with the spndle properly seating.

See coolerman's webpage to learn more.
 
did you get the inner cage assembled properly in the birf bell? IE the recess for the thicker snap ring in the correct position?
 
did you get the inner cage assembled properly in the birf bell? IE the recess for the thicker snap ring in the correct position?

When I took my Birf out I only removed the balls in the birf and not the cage. I inspected it and put the birf on my 40 axle.

I'm going to remove the martack and go back with the regular clip. What a pain in the ass!
:popcorn:
 
Ok, now I've screwed myself!!!!!

I used a hammer to tap on the end of the axle to see if it was seated all the way. Well with my martack, it seated itself so tight in the diff that I can get my axle out. I went to autozone and borrowed at slide hammer tool and used a chain and bolt to attach it to the birfield. Well it pulled my whole %&@*!? birf off but left the axle stuck in the axle housing. I don't know how I'm going to get the axle out.

Can anyone tell me if I drill and tap the end of my axle and do the same thing with my axle as I did my birf if that will hurt my axle? I don't know how else I'm going to get it out.

HELP!

ETA: Starting a new thread to help w/ this.
https://forum.ih8mud.com/40-55-series-tech/364027-help-i-really-screwed-myself-axle-issue.html

Nick
 
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LOL

Install the clip on the end of the axle, wrap axle with chain, attach slide hammer to chain. Should pop right out. Is enough sticking out to get a pry bar on it?
 
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My guess is that your martack is your problem with not getting the birf in far enough. In my opinion, the martack is definitely worth it. However, for my 71, I needed the martack to be in at about 1 1/2" or farther in. Basically, where the splines angle down to the shaft. I had the same problem when I had the martack too far out. A dremel tool took care of this quickly.

Now you just need to get the axle out!

Good luck!
:cheers:
 

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