Best Way To Remove Broken Timing Cover Bolt

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carnerd3000

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Sounds like it's in need of calibration them. But definitely pick up an inch pound wrench. I picked up an Icon from HF recently, very nice wrench, good accuracy too.
Yeah, if I really need one, I wouldn't mind the Icon. I definitely want the Snap-On digital wrenches, but of course I don't have the money for it.
 

Frank Enstein

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Put the cover on with a LITTLE bit of silicone gasket maker on a squeaky clean surface.

Tighten the bolts finger tight. Go do something else for awhile to let the silicone cure.

Come back tomorrow and pull the bolts one at a time and put a lock washer and a dab of blue thread locker on it and tighten until the lock washer goes flat and no more.

The silicone fills in any imperfections and glues the cover in place.

The blue thread locker keeps the bolt from winding itself out as well as keeping corrosion out. It will come out with zero drama several years later.

The lock washer is a spring that keeps the gasket/silicone under pressure with temperature changes.

Do the dance of joy and never touch it again!:gay:
 

Frank Enstein

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8 ft/lbs. is about as tight as a nut driver will comfortably be snug.

As you tighten the bolt (any bolt) the effort will ramp up steadily as it rotates in a very linear way. As you approach "snug" the torque will ramp up much more quickly. You will see this as the lock washer goes flat the torque will double in 1/4 turn when it gets snug.

I use this one.

 

Schurkey

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Torque wrenches tend to be much less accurate at the extreme low end of their range. I'm guessing that this is a 3/8 drive, 10lbft to 80lbft set to 1 notch below 10? If so, you may not have even felt the click. I've had that problem trying to use a wrench at too low a setting.
The "click" gets louder if you use an extension between socket and torque wrench.

I have the 3/8 ft/lbs. Duralast wrench, and it ranges from 5 to 80 ft/lbs.
For decades, "Industry Standard" was for the lowest markings on a torque wrench to be 20% of the highest marking.

Criminals figured out that they'll sell more torque wrenches if they mark lower torque values on the wrench than the "20%" amount.

Just about guaranteed that the torque wrench has lost all hint of calibration at that low level. But you could send it to Team Torque or to Angle Repair (or perhaps someone else local to you) and find out for sure.

Sounds like it's in need of calibration then.

I definitely want the Snap-On digital wrenches, but of course I don't have the money for it.
I lusted after digital torque-angle wrenches...until I figured out it cost more than double to get them inspected/adjusted/calibrated. About $50 for old-style clickers; about $125 for electronic units.

The only advantage a deflecting-beam torque wrench has is that they never need to be calibrated. The wrench itself is inherently accurate. They're just a hateful pain in the tuckus to use--all the error with them is due to the operator, not the wrench.
 

Erik the Awful

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I don't normally use a torque wrench on oil pans, timing covers, valve covers, water pumps, etc. I tighten by feel. Once you develop a feel, you can feel it if a bolt starts to stretch and avoid breaking it off. Once the bolt or nut snugs down, give it a little more tightening, and you're done. Using a torque wrench, I've stopped tightening short of the "correct" torque because I felt a bolt stretching.

Just so y'all don't think I'm a cro-magnon, I absolutely torque wheels, main caps, rod bolts, head bolts, etc.
 

Schurkey

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If you can "feel" a bolt stretch...it's already ruined and needs to be scrapped.

The only bolts that you'd "feel" stretch and not pitch in the recycle bin are Torque-To-Yield hardware that's intended to stretch (once) upon assembly. TTY bolts are designed to be a one-use fastener, often by engineers working for companies that advertise how "green" they are. Show me an assembly held together with TTY fasteners, I'll show you something that should have been designed with reusable bolts one size bigger holding castings that are more robust.
 

Erik the Awful

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My point was that you can feel the bolt stretch before you have to break out the extraction tools, but yes, the bolt is already ruined if you feel it stretch.
 

JeremyNH

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With respect to @Frank Enstein the plastic vortec cover uses shoulder bolts so a lock washer won't work. With shoulder bolts you have very little resistance until the shoulder hits the block at which point you get infinite resistance. At that point you are only tightening to prevent them from backing out but are not applying any more force on the cover itself. GM did it this way to prevent the bolts from being torqued all the way through the cover. 106 in-lbs is too high. I had thought it was 70-90 in-lbs. Regardless it isn't the kind of thing you actually need a torque wrench for. 90 in-lbs is wrist-tight. When I did my plastic cover a year and a half ago I put the torque wrench on the first one and then figured I was being overly **** given how low the torque was. They're shoulder bolts. I used some thread sealant to add a little back-out resistance and a ratchet screwdriver to do the rest. The cover did leak but it was because of the inlaid rubber gasket. Look at the back of your Dorman cover and you will see the gasket stops right before you reach the bottom edge on both side. Not at the edge but before the edge and that is your channel for leaks. You need a dab of RTV there or you will get a slow leak (a drop every 10sec or so) there. I swapped to the Holley aluminum cover which has a proper gasket and standard through bolts so if you wanted to use Frank's suggestion on lockwashers it make sense. I didn't though, just gasket tack and 7.5 ft-lbs and 18 months later no leaks.

With regards to the broken bolts though no help, sorry. Wish I could help but I've broken enough bolts on small engines for yard equipment that I'm terrified of repeating on my truck motor. I've never had any luck with bolt extractors. Tries maybe a half dozen times and am batting all balls for the effort. Granted, self-tapping bolts in an aluminum block aren't the same thing as a machined iron block with graded bolts but still the fear is there. It's heat and kroil to get bolts off and careful torque to get them back on.
 

thinger2

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So I'm working on the timing cover and the intake manifold gaskets on my Suburban, and since last week I got into a jam regarding one of the new bolts to the new timing cover breaking off due to being overtightened. I was trying to do the torquing to spec, which is supposed to be 106 in/lbs., but it turns out the torque specs may have been too much. That or the bolts themselves weren't up to par to handle the torque specs. Anyway, 4 of the bolts broke inside the block while I was tightening (and unfortunately I didn't figure that out on the first one I broke :p) and I was able to get out 3 of them by kind of unscrewing them out with an awe. The last one was coming out, but then it became difficult as it became flush with the screw hole, and then it became hard to spin it out with the awe, and I believe it's because I can't get a good angle on it with the PS pump bracket in the way. I also did try drilling it out, but all it really does is just scrape away the bolt, and not exactly drill through it. I don't know if my drills aren't fast enough, or if the bits aren't hard enough against the bolt.

With that being said, my next plan was to get some cold chisels and then kind of crack the bolt free. Is this an okay idea, or should I do something else? And if it's possible, I was wondering if anyone could tell me what the material of the timing cover bolts are. I got the Dorman timing cover number 635-505. Maybe I should get harder drill bits too?

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Okay, a lot going on here but Ill give it a shot.
Torque matters on main bearings and rod bearings and heads and intakes
Things internal to the function of the engine.
Torque doesnt really matter so much when you put in the "tin"
The front cover, the oil pan, the valve covers etc...
That is much more about having those surfaces clean and flat and straight.
A factory torque spec is exactly that.
It is a from the factory torque spec that comes from the line and is based upon in house inspected and calibrated and certified torque wrenches.
Most people do not have acess to those tools.
And, just a general rule of thumb.
The smaller the fastener, the smaller the tool.
Look at the diameter of the bolt.
And use the extension that is closest to that diameter.
You can only
And start with that.
My recipe for drilling out a broken fastener.
Start with a spring loaded center punch
Also know as an automatic center punch.
Eyeball that punch as close to dead nuts center as you can and pop it.
It makes a very small divot.
Look at it again.
If it is a bit off center, angle that punch and pop it again.
You are just chasing that metal back to center.
When you are happy with your center.
Bang that auto punch a few times to set that divot as the one you are going to chase.
Now you take a hard steel punch and establish that dent as a a landing spot for the drill.
Start with a really high quality high speed steel bit.
An HSS bit.
And then it is all about feeds and speeds and keeping it centered and cooled.
The goal is to drill dead nuts straight through the minor diameter of the thread and leave the major diameter stuck so you can chase it out with a thread chaser or a tap.
Whatever you do, dont try any kind of an "easy out" or any other miracle tool on it.
The only thing worse than a broken bolt is a broken bolt with a chunk of heated O2 tool stuck in it.
Get a couple of really good drills, Center those drills .
Keep them cooled while you drill with something
Even wd40 will work.
Low and slow and steady.
If you go full throttle crazy, you super heat the end of the bit and it doesnt cut anymore.
That heated end of the bit hardens the spot you are trying to cut.
And burns the drill.
So now you need a harder bit to cut through that.
But, the harder the bit, the more brittle it is.
And the the more brittle the tool, the faster it snaps off from a side load.
And that is my personal and opionated history of the "Heiicoil"
 
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