Frozen Brake Pad Retaining Pins - Drill Them Out?

[Mex]

I'm in the process of revitalizing the brakes on my 84 Carrera, and naturally it's proceeding smoothly and exactly as documented in the manual :|

After pulling the calipers off the car, I was removing the brake pad retaining pins when this happened:

The frozen pin didn't budge, and the tip of the screwdriver I was using as a punch embedded it self deep into the end of the retaining pin. At that point, I went to find a second opinion - but found some beer instead - and decided to just let the problem lie for a bit.

I've read quite a few threads on this problem, and it seems like most people use heat, PB blaster, punches, or a combination of the three. I don't have a torch, and penetrating fluid and punches have failed so far (and I don't see them working in the future as the end of the pin has now expanded in the hole).

I haven't encountered anybody who has drilled out the end of the pin from the hole, though, a la removing a stuck screw. Is there a reason for that? It doesn't seem any more potentially hazardous than the torch method to me, not to mention significantly less time consuming.

Is my logic flawed? Has anyone here tried a technique like this?

[john walker's workshop]

A screwdriver is not a punch. Get proper tool.

[Mex]

Originally Posted by john walker's workshop

A screwdriver is not a punch. Get proper tool.

Yeah, noted, going to track one down later today. Unfortunately it's pretty difficult to find specific tools over here since I don't parli much Italiano, and Italians don't generally do their own maintenance.

Do you have any tips on how I could fix this, though? Does this look like something I could still get at with a proper punch and some penetrating fluid?

[TRE Cup]

Drilling is not a good option! the pins are harder than the cast iron caliper. So if you attempt to drill, the bit will wander off the pin and ruin the surrounding casting.
Go buy a small propane torch kit from a hardware store and some proper drift tools. Remember to wear eye protection and leather gloves

good luck

[Mex]

Originally Posted by TRE Cup

Drilling is not a good option! the pins are harder than the cast iron caliper. So if you attempt to drill, the bit will wander off the pin and ruin the surrounding casting.
Go buy a small propane torch kit from a hardware store and some proper drift tools. Remember to wear eye protection and leather gloves

good luck

Ah, good to know, I didn't realize that. I'll give that a shot, I appreciate the help.

[85911]

And, use a punch as close to the diameter of the hole as you can find. A smaller punch will bore into the pin and expand it in the hole making its removal worse. Use a lot of PB Blaster. Put gloves on and see if you can cut the pin with a hack saw blade. Try grabbing the back half with vise grips and hammer them to move out the back half, then then do the front half. Or, put a screwdriver in the cut slot and hit it to drive out the back half. Punching out one stuck part of the pin may be easier if they are both stuck. And, ^, heat will help.

[Drisump]

Spray penetrating oil and tap body of the caliper near the pin. The vibration allows more of the oil to fall down the bore. Repeat for a number of times....then use the proper tool. i've never had any serious problem removing these, even when mounted on the car. Good luck

[Ian Comerford]

And then make sure you use copperslip grease on the new pins to stop this occurring again

Ian

[sugarwood]

I am a clueless n00b, but I will offer this:

The screwdriver tip may be wider than the hole, so I would not try to push it all the way through.
You can punch the pin out from the other side. Just buy a punch and a 4lb hammer.
I bet you can just smack everything back out from the other side.

I used to assume all hammers are the same, they are not.
A heavy $12 hammer carries a lot more force (F=MA)

[DRACO A5OG]

Two options:

That pin is toast so use another pin as a sacrificial pin and use it to drive it out. Order two or four more sets to give the car a new start. Good idea about copper anti-seize or better yet Nickle based anti-seize is even better to resist heat.

The other option, use a needle nose vise grip and clamp the shaft of the pin and use a hammer to tap it out. Maybe a little heat on the caliper could help.

Heck third option, find a steel nail the same OD ( a bit smaller ), grind off the point and use it as a punch.

[psychoideas]

^^^

This!

[Mex]

I really appreciate all the responses guys, thanks. I'll post up an update once I finish.

[Fleming]

Mex,

It is quite possibly the problem is the corrosion on the surface of the pin, look at the little rusted bumps along the length of the pin - they may be enlargeing the overall diameter of the pin and are now forced into the other side of the caliper. Take a strip of emery (sand) paper and do a surround cleaning/grinding of the total length of the pin before you do anything more.

Lubricate the pin with your favorite penetrant - (1/2 ATM fluid and 1/2 Acetone is far more effective than any commercial product).

Tap the pin from the other side to get some movement and grab hold of the pin with a vice grip and rotate it. (Don't deform the surface or you will have to file off the burrs to get it thru the caliper hole).

Once you get rotation and in-out movement it should slide out with a light tapping.

[djpateman]

Originally Posted by DRACO A5OG

Heck third option, find a steel nail the same OD ( a bit smaller ), grind off the point and use it as a punch.

I think any nail will be too weak to use as a punch; possibilities of failure and injury are very large. Use a proper punch.
Another option: take it to a machine shop.

[DRACO A5OG]

^^^ I have to concur if it is rust welded in like OP.

Try the vise grip and break the weld by twisting it but machine shop could do it properly for sure

[steely]

Originally Posted by sugarwood

You can punch the pin out from the other side.

No, you cannot do this, the pins have a head on one side.

[rusnak]

You are going to have to cut that pin close to the caliper. You will have to use pliers to push the pin out through the back side, then with a proper steel punch, drive the pin with broken screw driver tip out through the front.

Hope that you have not damaged the caliper too much up to this point.

[john walker's workshop]

Originally Posted by steely

No, you cannot do this, the pins have a head on one side.

Many also have a reduced diameter tip. I'm sure a few blows on a proper punch will get it out. Do you feel you can safely work on the most important part of the car if you can't get a simple pin out, or should you just take it to a shop?

[steely]

Originally Posted by john walker's workshop

Many also have a reduced diameter tip.

I was referring to the OP's, it will only go in one direction.

[ghost_of_butzi]

First, get the correct diameter punch (just a bit smaller than the pin), which would be harder metal than trying to use an old pin as a punch. Then slide the pads to the side and use a micro torch like this to really heat up the pin by applying the tip of the flame to the center section of the pin.
http://www.powerprobe.com/webstore/image/cache/data/Micro%20Torch/ppmtimg03-700x700.jpg

Try to hold the torch at an angle that doesn't also heat up the nearby piston and seal. Get the pin super hot. You can try to punch it out while hot, but if that doesn't work let it cool back down and try punching again. (The heat will help crack the corrosion at the interface, even after it cools.) If that doesn't work, heat up the pin again but only to about 200 degrees, shut off the torch, and carefully add a little PB Blaster or penetrating oil to the pin interface on both sides of the caliper. (If the pin is too hot, the oil could catch fire. Be ready for it.) As the pin cools, it will draw the oil down into the interface with the caliper.

While hammering the punch, have the caliper against a solid surface, such as a piece of hardwood. If you're holding the caliper or have it on a piece of rubber or carpet, you're not going to get the kind of sharp impact you need.