# Remove rusted hardened pin from cast housing



## dansawyer (Feb 24, 2022)

I have a frozen pin rusted, seized in a cast housing. The pin is hardened, 1/2 inch in diameter. The cast housing is about 1/2 inch thick. 
I have been taught to heat the housing so the hole expands and remove the pin while the housing was hot. The threads I read said to heat the pin and let it cool, then remove it. Which is correct? 
I was not going to heat the housing beyond 500 deg F.


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## benmychree (Feb 24, 2022)

The housing and pin would get hot at the same time to little effect, I think; I would heat the pin itself quickly with a oxy/acet. torch, then let it cool off as was suggested.


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## Dan Krager (Feb 24, 2022)

I've seen both methods used successfully.  Sometimes in tandem, letting things cool thoroughly first. It's hit or miss which works better, IMHO.  The method to use is usually chosen by how easy it is to thoroughly heat one of the parts. 

The most reliable method I've had exposure to is to be very patient with a 50/50 mixture of automatic transmission fluid and acetone applied to the joint and let it rest overnight. It seems to work without the need for heat in most situations.

DanK


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## Jim F (Feb 24, 2022)

BG In-Force penetrating oil.
Best stuff out there.


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## IamNotImportant (Feb 24, 2022)

When i was on the big gray thing.. the airdales would use Wintergreen Oil to break rusted bolts loose.. at sea


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## RandyWilson (Feb 24, 2022)

Heat everything, then use compressed air to cool the pin quickly.


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## brino (Feb 24, 2022)

I assume something like a dowel/alignment pin in a housing cover?

It may not be just rusted in, if it has a thread locking adhesive, then heating either/both and use a slide hammer.

Is the pin in a thru or blind hole? Perhaps it can be punched out, but be careful on the cast-iron!

Pictures might help here.

Thanks,
Brian


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## dansawyer (Feb 24, 2022)

The pin is about 1 1/4 inch long. It goes through a clevis which goes over a cast iron bar about 3/8 inch thick. The order is first clevis half, cast iron bar, second clevis half. 
This post is seeking advice on trying remove the pin leaving the clevis in tact. 
(If that fails I will grind off the clevis arms and try to remove the two halfs and then use an air hammer drive out the pin. This would of course require having a replacement clevis on hand. )
Thank you all in advance. Dan


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## dansawyer (Feb 24, 2022)

The pickle fork was used to try ot rotate clevis. The pin head in the center of the picke fork. There is just over 1/16 inch free between the pin head. .


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## tq60 (Feb 24, 2022)

Die grinder and CARBIDE burrs.

The pin is likely had on outside and heat may be issue.

1/4 die grinder is 20 bucks and burs about same.

Get a GOOD ONE from industrial supply.

Look for 1/8 sizes too as grinder should come with both sizes collets.

It takes time but you start at the ends and work in being very careful.

Cut from center towards outside and use ATF as coolant.

Cover all of it as the vibration and heat will allow it to soak in.

If you get a hole started in one end you may be able to drill out the center.

If so, work up to larger sizes but do not go all the way to end as that leaves something to drive the pin with via a drift punch.

Sent from my SM-G781V using Tapatalk


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## extropic (Feb 24, 2022)

The pin is a clevis pin, with a head on it, right?

How is the pin retained (before it rusted in)?

I doubt that the pin is very hard. I would try warming everything up with a torch then douse with penetrating oil and let it sit for an hour or so.
Perform multiple cycles, maybe 10 over a couple of days. Concurrently, try drilling and tapping the pin, 3/8-24 if you can. Thread a stud into the pin. place a short length of tube or pipe over the head of the pin/stud. Use a nut on the stud (over a plate with hole) to draw the pin out.

The pin may loosen during the drilling and tapping process if you get a few heat/oil cycles on it.

To your original question: the hole grows more than the pin (for parts with the same CTE).

PS: Your OP did not describe the actual circumstances well.


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## dansawyer (Feb 25, 2022)

Thank you all. I will try heating up. I will focus on the pin and let it radiate outward. I wiil start with butane; if that does not work I will switch to oxy-acy. I have a digital themometer and will limit the cast arm rise to 500 degrees F. That should prevent any damage to the cast arm. I will spray the joint area with PB Blaster at the end of a heating cycle.
There is sufficient space, gap, between the head and the clevis to insert a wedge. I have ground a wedge tool from an old nail puller that fits in the gap between the head and the clevis. I will use that to try to brake it loose.


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## Papa Charlie (Feb 25, 2022)

If that does not free the pin up, you can drill the center of the pin out, this will relieve the tension on the pins outer walls and make it easier to remove.


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## davek181 (Feb 25, 2022)

In automotive applications where a stud breaks off in a flange or anywhere for that matter, if you can get at the end easily, the best way to get it out is to weld a nut onto the stud.  It superheats the stud but leaves the flange or whatever cooler, and it usually comes out, or your weld breaks and you repeat the process.  

I thought it counterintuitive at first thinking the smart way was to heat the housing or flange and expand it around the stud, or pin in this case and remove as the outside expanded.  I have used this technique many times with success after i finally got past my mental block and tried it.

I also got a hint from a friend who builds heavy equipment.  If you have to heat something around a broken or seized part to remove it, he says don't try to heat the whole thing evenly, rather just heat one part of it.  He claims it works as well or better that way.    I have not tested this yet, but I bet it works  because broken equipment is his life and he knows a lot of things, and can build anything.


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## JimDawson (Feb 25, 2022)

The good news is that the materials involved appear to be forged steel, not cast iron. Looks like a brake can on a truck or similar.  I would first try the acetone/ATF mix, if that fails, then I would heat the pin to red, and cool with a dripping wet rag.  It should pop right out.


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## Steve-F (Feb 25, 2022)

This stuff works wonders!!









						Kano Laboratories 12KS 13oz Aerosol Kroil Original Penetrant Oil PN#KS132
					

The Kano Laboratories 13oz Penetrating Oil is a long-lasting lubricant that displaces moisture and rust proof protection. It is suitable for use in tight places and industrial quality.




					www.toolup.com


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## Martin W (Feb 25, 2022)

Is this a front air brake chamber? Heat the pin with a torch and use an air hammer with a pin punch adapter.
Martin


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## Jake M (Feb 25, 2022)

Those parts are steel.  No cast iron worries, heat won't hurt 'em, but you want to get in and out  quick, as there's a rubber diaphragm on the other end of that pushrod.  The clevis and pin kit is under ten bucks, and the clevis or the pin (probably both) is gonna be out of spec by the time you get it apart anyhow.   How much do you want to save on what looks to be a steering brake?.  Cut it.  

What is the failure here?  Why does the pin need to be removed?  Which parts need to be updated?


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## dansawyer (Feb 25, 2022)

Yes, it is an air brake part. When air pressure is applied to the brake chamber it pushes on the rod, the clevis, and the pin. The pin then pushes on the arm that rotates the S cam rod and the brake shoes (not in pix). The pin is supposed to rotate in the 'arm' - it does not. I am a new owner, this may have been seized for quite some time. When I discovered it the anjustment mechanim had tried to compensate for the lack of rotation.
My largest concern is the integrity of the arm. I am glad to hear it is forged and not cast. A forged part should have a greater tolerance to head.
My second concern is the integrity of the rubber in the chamber. This could be inconvinient but is a straigthforward repair. I will apply more solvent and then more heat.
Thank all. Dan


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## Jake M (Feb 25, 2022)

The pin goes through the yoke, and through the slack adjuster, and there is a bushing in the slack adjuster, that may or may not be frozen to the pin.  Does the slack adjuster (in between the yoke ears) have any "wiggle" there?  If the pin is frozen to the yoke, but not frozen to the slack adjuster, it's not a problem.

Absolutely and categorically, slack adjusters DO NOT respond to any lack of rotation, in that pin or anywhere else.  They ONLY respond to over rotation, and it's referenced by that bracket clamped under the nut that retains the chamber.  That bracket interfaces with an arm on the slack adjuster.  Although there are exceptions, usually there are no "settings" to that, it just needs the bracket as it's fixed reference.  What exactly is the brake doing?  Or not doing?  Do you know what size the chamber is?   Have you by chance found any tags or markings on the chamber?  It'd be a type (type 20, type 24L, or any tags or stamps indicating a stroke length?  Sometimes around the clamping band, sometimes on the body, sometimes on a tag that's affixed around the port that has the brake hose attached.  And by a long shot, do you know what type of brakes are on the axle?


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## FOMOGO (Feb 25, 2022)

I think a 3" cutoff wheel on a die grinder would be quicker and easier than burrs, if you want the head off the pin. Mike


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## dansawyer (Feb 26, 2022)

The failure is: The clevis is supposed to rotate on the arm to allow the rod to remain centered on the brake chamber hole. The pin is frozen so when the brake is applied the rod gets jammed against the side of the chamber, causing it to hang up. This in turn causes the brake to drag. I believe it was caught early and no damage to the shoes, drum, or bearings was done. I will change and inspect the bearing oil to ensure it does not show damage.
My thought is the only way to assure it is working is to remove it, clean it, and re-assemble. The thought is if the pin is free to rotate in the arm it will not hang up.
If I can get it free enough 'in situ' there is a possibility it may be operable with monitoring without actually removing it. It is currently fully operable, the arm retracts normally and the wheel is free. My fear is it could re-seize without warning.
Thank you. Dan


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## Jake M (Feb 27, 2022)

I see.  So I'm gathering from this (but open to correction), that this WAS binding, but you've got it to a point when it binds less?  When that happens full on binding happens, if all else is well, "normally", the pushrod binds on the way out under the full force of the chamber, but still releases until the rod rubs on the opposite side of the hole in the chamber, and stops short of a full retraction.  The shoes run too close, which isn't good, but they release.      The pushrod rubs and grinds, but it releases.  In my shop, that would have a new clevis,  pin, and bushing obviously, but if it stuck in the "out" position, the light releasing force makes me think that the anchor pins, rollers, main spring, and cam bushings are suspect.  The wheel would be coming off, and all of those items individually inspected.  These brakes are dirt simple, almost archaic in their operating mechanisms, which is what makes them as good, and as reliable, and durable as they are, but they do work as a balanced system, and rely heavily on everything being dead nutz right.  What's good enough on a static test is way different than what works under normal  service conditions.  Bottom line, whatever you find when you get in there, make sure that you're sure, and never forget that rust seldom gets to only one place.

FWIW, if it's got hot enough that the bearing oil smells "cooked", (or if there's barely visible "glitter" in the bearing oil, but that's somewhat it's own issue), cups and cones are done, and will continue to disintegrate no matter what oil you put back.  Replacing those is a given as well regardless of their appearance), but if the oil is burnt, the friction material has been past it's point of no return (that's where the heat came from after all), so no matter what you do, it'll never be as effective as it was.


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## finsruskw (Feb 27, 2022)

Jake M said:


> I see.  So I'm gathering from this (but open to correction), that this WAS binding, but you've got it to a point when it binds less?  When that happens full on binding happens, if all else is well, "normally", the pushrod binds on the way out under the full force of the chamber, but still releases until the rod rubs on the opposite side of the hole in the chamber, and stops short of a full retraction.  The shoes run too close, which isn't good, but they release.      The pushrod rubs and grinds, but it releases.  In my shop, that would have a new clevis,  pin, and bushing obviously, but if it stuck in the "out" position, the light releasing force makes me think that the anchor pins, rollers, main spring, and cam bushings are suspect.  The wheel would be coming off, and all of those items individually inspected.  These brakes are dirt simple, almost archaic in their operating mechanisms, which is what makes them as good, and as reliable, and durable as they are, but they do work as a balanced system, and rely heavily on everything being dead nutz right.  What's good enough on a static test is way different than what works under normal  service conditions.  Bottom line, whatever you find when you get in there, make sure that you're sure, and never forget that rust seldom gets to only one place.
> 
> FWIW, if it's got hot enough that the bearing oil smells "cooked", (or if there's barely visible "glitter" in the bearing oil, but that's somewhat it's own issue), cups and cones are done, and will continue to disintegrate no matter what oil you put back.  Replacing those is a given as well regardless of their appearance), but if the oil is burnt, the friction material has been past it's point of no return (that's where the heat came from after all), so no matter what you do, it'll never be as effective as it was.


Older piece of unknow equipment??

Replace the assembly and be done with it.
Be DOT safe is much more important than saving a few dimes.


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