How to pull broken bolts out of Harmonic Balancer

syphon

Registered User
Hey everyone,

Recently I thought my Harmonic Balancer went out, but it turns out that the bolts holding the crank pulley on the HB were broken.

I removed the pulley and this is what I saw
HB1.jpg


I managed to remove the two little stubs you see sticking out, but there are still 2 bolts stuck inside the holes there.

I can't get these bolts out for the life of me. I bought some drill bits and EZ Out bolt removers. The 5/64 drill bits broke almost immediately, and then 7/64 broke. I also fear I may have messed the threads up on one of the holes already.

Tomorrow I'm going to go and try to find stronger drill bits, but I dont know if that will work. Do you guys have any advice for getting out these tricky bolts?
 
Do yourself a huge favor....

Don't waste your time and effort trying to remove the pulley bolts. You might as well remove the balancer itself while you still can. Chances are that the bolts breaking out are just a symptom of a balancer going bad.

Trust me on this one, you don't want to wait and find out the hard way that you need to change the balancer. It is not a fun job removing the broken balancer..

I think others on this board would agree, change the balancer, it is not often that you get a warning like you have.

Phil Stocker
 
I agree with phils. Change the balancer out, and go with the Billet solid balancer.

If you are short on cash and just want to get it running again, then there is only one way to get rid of the broken bolts. Drill a hole in the remaining bolts, and go out and purchase a couple of "Eazy-Outs" can get them at any hardware store, or auto parts store. They are reverse threadded things that look like a tapered tap. The more you twist on them the more they bite into the broken bolt, and then they remove it without screwing up the threads.
 
Those bolts are grade 10, nice and hard.

I agree that you should replace the entire damper assembly. If you have damaged the threads then you will have more problems with the pulley in the future.

Aaron
 
I have some advise for you....you can salvage it!

I had the exact same thing happen to me a few years ago.
Use a balancer puller and remove the balancer from the motor.
Flip the balancer over, remove the small screws holding the crank sensor vane to the balancer and remove it (pay attention to location, there is a location hole) Mark it so it can be put on the same way.
The vanes can be bent easily, you don't want to ruin your crank sensor.
I used a Snap-On extractor set. This type is straight and has four ridges on it that can be pounded completely through a broken bolt. It comes with matching drill bits. Any pro-mechanic should have a kit like this.
Drilling these is tedious, the bolts are hardened steel, and the balancer is aluminum, so it is important to drill straight. Use a pin punch and peen the end of the bolt to keep the drill from wandering. A drill press would help here, but I did it by hand very carefully.
I then punded the extractor completely through the bolt, and put the adapter on the extractor, and using a wrench, I was able to get the bolts out. (Whew)
I then chased the threads in the balancer with an M8X1.5 tap to clean the threads. Luckily, none were damaged.
I took the balancer and the pulley to a machine shop and they fixed me up with 4 allen head grade 8 machine cap screws and lock washers. With the sensor vane off, you can see that backside of the holes. Make sure that you get bolts that reach all the way to the end of the threads! Too short of bolt and you will probably pull the threads out of the soft aluminum.
Make sure that you check the entire balancer for cracks as they are prone to breaking. If in doubt throw it out.
TIP: You do not need a special tool to re-install the balancer. Make sure you use some silicone in the end of the keyway as the slot is cut through the whole balancer. You can probably see where the old silicone was.
Line up the key way and push the balancer on as far as you can with your hands. Then put a block of wood against the balancer nd tap it with a hammer to push the balancer on more.
Once it's on far enough to get the main crank bolt started a couple of threads, spin the crank bolt in and as you tighten it, it will pull the balancer on the rest of the way quite easily. Be sure to tighten it to the correct torque.
Install the crank pulley, I use red loctite 262 (not much) and lock washers too. I have had them out since (twice) so the red loctite is not too harsh for this application. Tighten the crank pulley bolts to 25 ft/lbs and you should be in business.
Once it's back together, start the car and check for pulley wobbles. If it is running straight and true it should be fine.
Mine has been okay for 5 years after this.....I now have 173,000 miles on the original balancer.

I think I'm going to replace it now because its getting pretty dang old!
Good luck.
 
Save yourself a bunch of headache...

Trust everyone on this one. It may sound expensive now, but if you DON'T replace it, you are looking at one hell of a pain in the A$$ to remove the broken hub from your crankshaft snout. I don't doubt that Katoom has had good luck with his fix, but I can tell you that the pulley bolts just don't break for any old reason!! You can fix it and put stronger ones in there place, but sooner or later, and without warning, that harmonic balancer WILL break, and it WILL leave you stranded on the side of the road with you kicking and cursing your SC wondering why the hell it won't start!!

What I did when mine broke, (I never thought it would happen to me, even after reading about many instances on the board where they broke off, I think my exact words were "My cars never leave me stranded, never!!!!!") I bought a new one from Ford, it comes with the balancer and pully as a matched set for about $275.00. The reason why they fail is because the rubber o-ring that is between the hub and the steel balance ring gets hard and brittle. This lets the balance ring slip on the hub, causing the harmonic balancer to lose its balancing capabilties. The vibration (probably very high frequency) then will snap the crank bolt, and the hub starts to "walk" off the crank snout. It gets just so far before it breaks off, leaving a good bit left behind the oil seal in the timing cover.

So, I bought the new HB and pulley. To somewhat protect the new balancer from road junk, oil, etc.., I used clear silicone sealant to seal the o-ring that is exposed from any external contamination. You would have to do this on the fron and back of the balancer to ensure 100% coverage. Install the crank ring back on the balancer, and install the new unit on the engine.

If you don't have the $$ to spend on a new steel unit, I think that this is the next best thing. It should protect the rubber from failure for quite some time past how long they would last unprotected. Do yourself a huge favor, and your car a huge favor, replace it now!!

Good luck

Phil Stocker
 
I must object to hammering a damper on or using the crank threads to pull it on.

THIS IS A VERY BAD THING TO DO. Think about where the shock from hammering the damper is going, straight into the crank and bearings. You cannot torque the crank bolt down correctly if you are using it to pull the damper on. You also need to grease the threads if you do this, then your going to have fun cleaning the grease out so you can apply thread locker. If you don't grease the threads, think about the damage that will be done to the threads.

Standard threads are not designed to pull things together, they hold things together. The threads on the installer tool are made differently. Machine threads are made to push and pull but have low static friction (they don't hold things well).

It's your car so do what you wanr but I am trying to say why it should not be done.

I am going to call the guy who has my tools and see when they will be available for loan again.

Aaron
 
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