I was removing the wheel bearing from the knuckle and broke a bolt. Grinded, hammered, pried, and eventually air hammered for the final separation.

Going to replace the wheel bearings.

BUUUUUT... I managed to take a small chip out of the knuckle right where one of the surfaces mates up. See the pic. I have pic of the affected area from 2 angles and a pic of one that is not affected.

It's not much... but ... it's my daughter's car... think its ok or would you replace the knuckle altogether?

 

That wouldn't worry me too much as the bolts come in from behind and hold the hub. Plus it's sunk inside the knuckle pretty far. The hub will seat on the entire surface anyway. If you were only going to use two of the three hub bolts, that would be a far different story (and not recommended). The underside of the hub bolt is taking the load on the one side of the knuckle and the entire surface of the knuckle is on the other. You may get water in there which will rust the bolt prematurely.

 

If it was you driving it, I would say go for it. But since it is your daughter, sleep better and replace it. Junk yards should have them at affordable prices.

 

There's nothing unsafe about bolting that up with the chip in my non-professional opinion. It's not structural-look at the hub, look at the seating surface. The three bolts hold it against the seating surface. Obviously, if unsafe he wouldn't be working on the Jeep - he'd take it to a mechanic.

Maybe we shouldn't even work on Jeeps unless we're Class A mechanics. Maybe we shouldn't drive 18 year old vehicles. Maybe we shouldn't drive period. Take the bus. Maybe don't leave the house either...

 

I'm with these guys... I think it will be fine. Just put some locktite on those and torque that one up last but stop before it starts to tweek and possibly break the bolt tab. The locktite should hold it.

 

OP, you have access to a MIG welder? Preheat with a torch just around the area to be welded, fill with weld. Then hit it with the torch right after, and put a little heat on it, take it off, a little heat, take it off, the point of this is to let it cool down slowly so it doesn't crack....grind smooth were needed, and chase the mount hole with a drill bit. It'll look like new.

 

Know what man? That is what is cool about you...

 

I would not think twice about it bolt up the new bearing . the bearing will seat all the way around the hub and the part of the ear that is not chip . I don't think I would weld it , I would replace it if it bothered you that much , bolt up the new bearing and torque to spec. then you can take it for a ride and when you get back you can recheck the torque .

 

Here's the problem with that...it's cast. Cast materials are brittle. Once compromised, cracking becomes a major concern. It may look "ok" but there's micro cracking you can't see. Micro cracks can become major cracks...and break. Remember, ALL the weight is riding on that hub, and where it mounts. That part sees a LOT of stress. I'd fix it. ESPECIALLY if it was my daughters car. I'd never forgive myself if something happened to her, that I had the opportunity to prevent.

IF IT WERE ME- I would repair, or replace. Preferably repair, as replacement is WAY more work.

My OPINION

Good luck sir!

 

Thanks to all for the comments. Very helpful. I don't have access to a MIG welder. That is a longer term project for me.

She uses the car primarily to get back and forth to school ... about 10 minutes each way, never really going over 40 mph. I am going to bolt it back up and get the car inspected. In the meantime, I'll hit the JY for a replacement. I saw a bunch of them there this weekend.

Thanks guys.

 

And of course you are right, be safe and don't take chances. My comment below was because somehow in only 2 and a 1/2 lines, you were able to share a lesson in the complicated process of welding cast...

 

My opinion for what it is worth is that this is no big deal. That is on the outside of the knuckle. The unit bearing is pulled into it and the bearing uses the entire rest of that machined surface to rest against. The bolts pull from the other side and none of those surfaces are compromised in the pic.

 

Agree completely.

 

I wish mine was only 18 years old, mine is 32 now I better put it on a shelf.

Doesn't the brake dust shield mount between the unit bearing and that part of the knuckle? So the unit bearing doesn't actually touch it at all.

 

Exactly my point-The whole Jeep is unsafe compared to a new car with 100 air bags, ABS, traction control, lane departure warning, blind spot detection, backup camera etc. How did we survive? My '67 had four wheel drum brakes and manual steering but it had a nice soft vinyl dash pad so that my head would hit that on its way to steel. Only front lap belts and no shoulder restraints. Also, the steering wheel would have cut me in half as it was so large it rested in my lap.

The hub fits in the opening on the knuckle. I think the opening in the dust shield is bigger and the shield is held in place by the bolts. Can't remember-I think I put mine on and forgot the shield the first time I did it!