Rusted Knuckle How Bad? (1 Viewer)

[zbrad]

I recently drained my differentials and noticed my front end was green. Reading about it, figured it was the axle seals and the grease and gear oil mixing. In about 3 weeks I’ll be rebuilding my knuckles (first time) I’m just away on travel until then. I took this photo of my knuckle before I left with abnormal rusting. How bad is this? Is this something I should be worried about when I’m rebuilding the knuckle. Any advice is greatly appreciated.

 

[LandLocked93]

Agreed your diff oil and grease are mixing.
Once you have the knuckle off, you'll have full access to the balls. You can get all that off with some sandpaper or wirewheel. Just need the surface fairly smooth (if it isn't already) for the wipers to make full contact.
Should be fine.

 

[Kernal]

Agree with above.

Post up photos after you've done the initial clean-up and rust removal. If you wanted to go a bit further, some hand sanding with long strips of progressively finer grit emery cloth, that works but you won't be able to remove all the pits (and you shouldn't try to).

Once all you have left are some pits then you can use a phosphoric acid rust killer (Ospho, Rust-Mort, ---) to kill the rust in the pits. After that's all dry (follow the directions on the bottle) you can paint the swivel balls using either Rattle can paint or (better) 2K catalyzed paint and epoxy primer like SprayMax which will last longer.

By the looks of your axle housing the whole thing could be treated, primed, and painted FWIW. If there's anyone in your area that can "sand" blast (media blast using something other than sand) the axle housing, that would be the ultimate way to go.

 

[mudgudgeon]

Needs a scrape clean and maybe a rub with some emery cloth.

What's going on here

Is this a gouge? Or just a rub mark.

 

[zbrad]

I appreciate all the insight and will definitely keep y’all updated with photos once I start. @mudgudgeon I believe that’s just a rub

 

[Kernal]

@zbrad definitely would be interesting to see what it looks like once the knuckle is off the vehicle and cleaned up a bit.

 

[GerhardUngerer]

I am dealing with the same thing now. The knuckles are very rusted. I used a wire wheel, composite wheel, sandpaper, and elbow grease. it is still pretty pitted.

Would it help if I put self-etching primer on it? Maybe just paint it with 2-part epoxy (West Systems)? Rustoleum Rust paint? Leave it be?

Do I just sand it more?

 

[zbrad]

I am dealing with the same thing now. The knuckles are very rusted. I used a wire wheel, composite wheel, sandpaper, and elbow grease. it is still pretty pitted.

Would it help if I put self-etching primer on it? Maybe just paint it with 2-part epoxy (West Systems)? Rustoleum Rust paint? Leave it be?

Do I just sand it more?

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I sprayed mine with some ospho then followed it up with 2k eastwood paint works like a charm.

 

[GerhardUngerer]

I sprayed mine with some ospho then followed it up with 2k eastwood paint works like a charm.

Filled all the gaps? What 2K paint did you use?

 

[zbrad]

Filled all the gaps? What 2K paint did you use?

I didn’t bother to fill in the pits just used Eastwood 2K

 

[Kernal]

The phosphoric acid products like RustMort (AutoBody supply stores) or Rust Kutter (Tractor Supply), or Ospho (ACE Hardware in the US) help to slow down/kill/convert the rust left in the pits, follow that with a primer and paint. I've used SprayMax 2k Epoxy Primer and 2k Black Topcoat, works very well together. They're not cheap, about $25-30 per can and they have to be used up quickly. Once the aerosol cans are activated the primer is sprayable for a few days, the topcoat for only ~24 hours before it hardens in the can.

Check out Summit Racing. One can of each is more than enough for the swivel balls, if you plan to paint the entire axle get at least two cans of each.

The Spraymax may be the same product as Eastwoods brand, Made in Germany.

Spraymax Epoxy primer comes in three colors, Beige, Grey, and Black,

Spraymax 3680034 SprayMax 2K Epoxy Primer | Summit Racing

Free Shipping - SprayMax 2K Epoxy Primer with qualifying orders of $109. Shop Paint at Summit Racing.

www.summitracing.com

The Hot Rod Satin Black is close to the original look (not full Gloss)
but maybe is a touch higher gloss than what the axle looked like when new.
FWIW

Spraymax 3680212 SprayMax 2K Hot Rod Black Paint | Summit Racing

Free Shipping - SprayMax 2K Hot Rod Black Paint with qualifying orders of $109. Shop Paint at Summit Racing.

www.summitracing.com

Follow the directions on all the products (go online to get instructions for Spraymax). It's obviously most Important to clean, clean, clean, before priming and painting, final cleaning with Acetone (the Green can of CRC Brake cleaner or Acetone from a hardware store paint section).

 

[Malleus]

I am dealing with the same thing now. The knuckles are very rusted. I used a wire wheel, composite wheel, sandpaper, and elbow grease. it is still pretty pitted.

Would it help if I put self-etching primer on it? Maybe just paint it with 2-part epoxy (West Systems)? Rustoleum Rust paint? Leave it be?

Do I just sand it more?

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Are you saving all this rust you're removing? You may a a full Jeep's worth by the time you're done.

 

[GerhardUngerer]

Ha, more than a jeep. I have a jeep and a jaguar's worth of rust.