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The brakes don’t work on my new used mower with a Peerless transmission. Turns out the pins are frozen with rust, and so was the longer of the two bolts holding it in place. I thought it was turning but it was just the head twisting off.

This should be fun. I’m going to remove the bracket and hopefully spin the brake assembly off the bolt, then try to back it out with a set of vice grips.

Spray the broke bolt first like day before with something good like Kroil, or your choice.

Might even need to heat up the housing to expand, then give it a try. Careful on the heat tho.

I can’t get enough of a grip on it to turn it out. I’ve soaked it in Kroil for a week but my vice grips just twist on the shaft. I tried jamming two nuts and turning it off with a wrench but it stripped the threads.

I‘m starting to think I just need to cut it off flush and use a LH drill bit.

If you have welder access, weld a bolt on the stud.

That happened to me awhile back.
I raised the rear of the mower up on a hoist so as to be easy to get at the twisted off rusty brake bolt.
Steel bolt going into aluminum. Severely galled threads.
Just slightly enough stub to get vise grips onto then took vise grips off, took a propane torch (could have used oxy/acyt but did not want that much heat)
and heated the aluminum housing around under the bolt stub, not excessive heating, just a good warming to expand the aluminum and took a hammer and pecked several times on the stub of the bolt. (was really lucky that it left little bit of a stub)
This heat helps break up the galled steel/aluminum around the threads. Heat peck try to wiggle. (patience)
Finally got a slight movement but still lots of pecking and wiggling.
Finally got it to come out but still had to go back and forth several times all the way out. I could have tried welding a nut onto the stub but I wanted to actually see the stub bolt itself as I was trying to turn.

I chased the threads on both and used anti-seize during assembly.
Probably took at least 30 min's just warming and pecking on the stub. (knowing that if I twisted off it would result in a bad thing)

Well, I broke it off so I tried to remove it with a LH drill bit and broken screw extractors. The drilled-out stub is still in there. I think I need some better broken screw extractors.

Elkins45 said:

Well, I broke it off so I tried to remove it with a LH drill bit and broken screw extractors. The drilled-out stub is still in there. I think I need some better broken screw extractors.

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Well that is one of two problems I have with those twist extractors. One is they are brittle and get sheared off. Second is they swell the screw you are trying to remove which makes it even harder to remove.

The problem you having is that steel has seized in the aluminum housing. The only solution I have found is to drill out and retap.

StarTech said:

Well that is one of two problems I have with those twist extractors. One is they are brittle and get sheared off. Second is they swell the screw you are trying to remove which makes it even harder to remove.

The problem you having is that steel has seized in the aluminum housing. The only solution I have found is to drill out and retap.

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That’s what I’m planning to do.

Edit: I’ve decided to drill it and tap it for a threaded insert. That way in the future it will be steel on steel.

Elkins45 said:

That’s what I’m planning to do.

Edit: I’ve decided to drill it and tap it for a threaded insert. That way in the future it will be steel on steel.

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Are you the dude on Taryl Fixes All videos?

Tiger Small Engine said:

Are you the dude on Taryl Fixes All videos?

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I'm trying to decide if this is a compliment or an insult.

He will still have problems later as steel will rust. It is about all he can do to effect a repair though. Sometime it is necessary to do this. Stainless steel is about the only thing that not corrode in damp environments.

In this case it depends how meat is available as to which type of insert he can try. Heli coils takes up the least metal on resizing. Now of course there are other types thread repair inserts out there too. Hopeful he can stay centered up and square.

If has sheared off an extractor in the hole it will take a carbide drill bit the cut it out as they are that hard and he has to be careful as not to go too deep and penetrate the casing. This is when a drill bit depth stop (limiter) is useful. This has happen to me several times so learned to just drill out the screws with carbide bits as many are grade 8 and are heat harden further.

StarTech said:

He will still have problems later as steel will rust. It is about all he can do to effect a repair though. Sometime it is necessary to do this. Stainless steel is about the only thing that not corrode in damp environments.

In this case it depends how meat is available as to which type of insert he can try. Heli coils takes up the least metal on resizing. Now of course there are other types thread repair inserts out there too. Hopeful he can stay centered up and square.

If has sheared off an extractor in the hole it will take a carbide drill bit the cut it out as they are that hard and he has to be careful as not to go too deep and penetrate the casing. This is when a drill bit depth stop (limiter) is useful. This has happen to me several times so learned to just drill out the screws with carbide bits as many are grade 8 and are heat harden further.

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There isn’t an extractor in the hole, just a tiny bit of the old screw. The clearance bit for the insert should remove it completely.

Elkins45 said:

There isn’t an extractor in the hole, just a tiny bit of the old screw. The clearance bit for the insert should remove it completely.

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Then you got lucky in that sense. IF it was me would had been the other way.

StarTech said:

Then you got lucky in that sense. IF it was me would had been the other way.

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I’m a little worried about how deep I will need to drill to install the insert, but I‘m hopeful than even if I break through the case the insert will fully seal the hole. That’s one reason I decided on an insert rather than a Heli-coil.

Maybe compare the depth of the other hole and also use a drill stop.

I think maybe I seen about 1 1/2 inches of threads on the one I was able to wiggle out.
Most likely 3/4 inch of good solid threads would be good. Just has to overcome the push force of the brake pucks when the brake is applied forcefully.
If it happen to drill into the oil might be possible to find a short allen screw and use in the bottom of the hole after tapping. I think mine was maybe 1/4 inch diameter bolts and a standard thread of maybe 1/4-20. (no metric stuff involved and I found correct size bolt in my go to trays.

What was sad about mine is I tried not to twist either one off, lots of pecking on the heads of the bolts before trying to loosen, then using a 6 point sopcket and a 1/4 drive for a good feel. I was lucky that when it twisted off it left me a 3/16-1/4 stud to grasp onto with channel locks, but I had to be careful with the channel locks when they got a good bite.
Aggravates me when I twist off a bolt or strip threads coming out, knowing I tried not to going back and forth reversing especially when aluminum/steel studs.

Another broken bolt "misery" thread. This was a game changer tool for the shop.

Back in business!

Drilled and tapped:



Insert installed:



Reassembled and adjusted:



I replaced the other bolt with a stainless one, but if I ever have to remove it again I'm just going to drill for an insert too.

It occurs to me that a smart fella might make backing those bolts out and giving them a light coat of anti-seize a part of his annual maintenance routine.

Ahh I see you use a Timesert but at least there plenty area to do it as that a larger hole than a Heli coil. I just had install a couple 5/16 5/8 Heli coils on crankcase cover [oil pan] on a Briggs 49M. Torquing the screws to 27 ft-lbs when I had one to strip right at 27 ft-lbs and on the second install another one strip at 18 ft-lbs. Lost the crankcase gasket as I did trust it after the second installation.

Glad I buy them a couple years ago for another Briggs 31 series project.

StarTech said:

Ahh I see you use a Timesert but at least there plenty area to do it as that a larger hole than a Heli coil. I just had install a couple 5/16 5/8 Heli coils on crankcase cover [oil pan] on a Briggs 49M. Torquing the screws to 27 ft-lbs when I had one to strip right at 27 ft-lbs and on the second install another one strip at 18 ft-lbs. Lost the crankcase gasket as I did trust it after the second installation.

Glad I buy them a couple years ago for another Briggs 31 series project.

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There’s a thin wall version that only requires a 3/8 hole but I thought there would be enough meat around the hole to use the larger one. I’m used to tapping steel so it was almost alarming how easy it was to tap the hole.

Imagine how much better it would be if the inserts were installed at the factory. But that would probably add $5 to the cost, and the accountants wouldn’t stand for that

Something else that occurred to me is that the design could be improved. The front bolt is at least an inch longer than it needs to be because it has to go through a spacer so the return spring has something to hook onto. You could remove the spacer and spring and use a shorter bolt, which would be less likely to shear.

The positive return for the brake lever could be accomplished by using the clutch/brake spring. Slide a piece of tubing of appropriate length over the brake rod behind the lever and it would force the lever forward when the clutch spring pulls on the rod.

Correct about the longer one in the front and is usually the one that twists off.

Lots of places on them machines that 5 cents of antiseize FROM THE FACTORY would really help us do it yourselfers, just to mention few places, the engine output shaft, the rear axles shafts, the brake puck studs.

The price of them brake pucks are also out of sight.
In my spare time as a winter project I've started making spare lawn tractor brake pucks after I seen the inflated prices for such. I take the automotive disc brake pads that are worn down past serviceable life on a auto, put them in a vise and take a oxy/acety torch and heat the metal backing until the glued on pad falls off and then cut/grind the disc brake pad to the same size as the pucks,
using a new puck as a reference.
I also custom make some blade brake pads which are also pricy.

Anti-seize would definitely all of us in some places or at least a thread sealant.

Elkins45 said:

Something else that occurred to me is that the design could be improved. The front bolt is at least an inch longer than it needs to be because it has to go through a spacer so the return spring has something to hook onto. You could remove the spacer and spring and use a shorter bolt, which would be less likely to shear.

The positive return for the brake lever could be accomplished by using the clutch/brake spring. Slide a piece of tubing of appropriate length over the brake rod behind the lever and it would force the lever forward when the clutch spring pulls on the rod.

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or replace the bolts with studs
makes the reassembly a lot easier and removes the gauling problem

First you got to the old screws out without breaking them or as in this case have to drill out and put in a Helicoil or other thread repair device.

Here it is the problem of finding the studs of the right length or even the materials to make custom studs. Making custom studs is usually beyond most DIYers. But they could use all thread rods cut to length.

Of course the DIYer can get lucky sometimes and find a commercially made stud the right length. McMaster-Carr carry studs but are limited in the selection they have.

StarTech said:

Here it is the problem of finding the studs of the right length or even the materials to make custom studs. Making custom studs is usually beyond most DIYers. But they could use all thread rods cut to length.

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I have tried the all thread to make studs but found it too soft for most things. If I want to make studs I cut the heads off grade 5 bolts.

Yep
A cut thread bolt ( most stainless Steels ones ) , remove the head & thread it
Even a cheap Scamazon / Evilpay tap & die set will do the job is done slow with enough lube .
I use a lot of studs BSW <> CEI or UNC <> CEI and make them exactly like this
Very easy to do

Question here. How do you keep the dies straight? I have tried free hand threading things like this and always end up off threading them. I figure I am going to need a threading lathe to this because I am so bad at free hand. Would tapering the end help?

And mentioning cheap dies and taps. I will never buy another set from HFT as they were pure junk. Cutting teeth missing and slag in the dies. Currently I buying my replacement die and taps from McMaster-Carr.

I am pretty good at free handling starting taps and dies. Sometimes I will take the belt off the drill press and chuck up the tap and put the piece in a machinist vise and twist it by hand to get it started.
Lots of hex dies suck for getting started. I prefer adjustable round dies. Usually have a better taper for starting. Grinding the end of the shaft to act as a starting pin in the die works pretty well too. Some hex dies are actually thread chasers and really suck at trying to start on an unthreaded shaft. I also cringe everytime I see someone on YouTube chuck a tap in a power drill.

Taps I have no problem with, it the dies. But while I sitting here you did me an idea but I will need to get a cross vise for the drill press. OF course do the threading un-powered as even at my drill press slowest speed it is way too fast for threading; although, I might try a variable motor speed controller for brush-less motor. I am not not a fan of pain.

I usually buy tap in sets of three. Taper, regular through hole, and bottom. Start the threading with the taper and finish up with one or both of the others.

I might buy one of adjustable dies to see how works for me here but it probably require me to buy holder too. But those have to wait a while as Insurance, taxes, and new uniforms are currently got my budget very very tight.

A $200 surprise shipping charge didn't help. When I call about the charges the rep said it was probably $40-$60 so I gave my customer his senior discount. Now I in the hole $80 on the sale. Now I can't trust the vendor to tell me the truth about shipping charges. I still can't figure why they shipped LTL when the package only weighted 46 lbs which is UPS-able.

A tip when using dies is to use the longest handled die stock you can. The longer it is the easier to keep it level when starting. I always laugh when I see guys on YouTube using an adjustable wrench to start a die.

In most cases you are only going to put 5 to 10 turns on a stud
So if it is not quite strait it does not matter all that much
One of the things I have been meaning to get for the past 25 years is a tail stock die holder but like Hammer. if it has to be very strait then is it die on the drill table & shaft in the drill press chuck
A 10 kg weight hanging off the quill feed while I work the quill pulley back & forth with both hands
If it has to be a very long thread like on some of the crankshaft end float tools I have made then it is start in the drill press the transfer to a vice .
If you really want to be keen then you can fit a pair of brickies line spirit levels to the die holder arms to make sure it is square
this is what they used at my high school to teach us how to thread square