Don't bother to ask why or how, just know it was an extremely stupid decision. I've searched the forum and need some more advice. Long story short, broke a bolt off into the crank when trying to install the hub. Pretty sure the bolt is seated into the crank which is probably why it broke when I kept turning it. About a 3/8" piece is in the crank and there are still some threads available.

I have already tried drilling the bolt and using an extractor, without success. The bolt also broke off uneven and I wasn't able to get the drill hole centered correctly, its off. So that isn't going to help me with removing using the extractor either. Only thing I was thinking was to drill the hole bigger and attempt to center this bigger hole a little bit an attempts to help and then use a bigger extractor.

But, could I just "forget" about it in a sense? The hub fits snug as most know, would there be any problems with this? Just need some more advice other then what I've found already. Thanks.

What I mean about "forget" is just tap the hub on or continue with the install tool I went out afterwards and found. Use the tool to install the hub and maybe a shorter bolt to install the wheel since there are still threads available for it to grab. I might also try to cut a slot into the bolt and use a heavy flat head to bring it out. Maybe another drill bit to just cut away at it until I can clear it...

 

No one can answer your question without actually looking at your problem. General rule of thumb with bolts is they need 5 rotations to hold. If you have 5, give it a shot. You don't have many options.

Seeing how you are off center, drilling is probably not a good idea. Last suggestion is weld the SOB on. BUT now I quote engine builder magazine. Specifically http://www.enginebuildermag.com/Arti...lt1_enige.aspx

"HUB AND BALANCER
The balancer is a two-piece assembly with a pulley that bolts onto the hub. Separating the two made it easier to install the Optispark distributor on the assembly line and out in the field. See the photo. The holes in the hub are offset, so the balancer only fits on it one way, but there’s no keyway in the hub to index the hub on the crank. This shouldn’t be a problem unless the damper was drilled at the factory to "trim" the final engine assembly.

If it was drilled a lot to compensate for an engine that was out of balance, you could end up with a shaker. If you encounter a balance problem try rotating the balancer assembly on the crank 90° at a time to see if it eliminates the problem. "

Every balancer I've ever seen was drilled. So if you can't take it off when you install it, you may never get it balanced. If it requires it.

 

Alright, well I'm going to see how many rotations I can get with a new bolt. If it's more than 5 I'll go ahead and use the new bolt and seemingly "forget" the broken bolt for now. If the new bolt threads good and holds I should have nothing to worry about for awhile. Plans are to eventually get a second dd for a beater and dive into the z for more work and upgrades so hopefully luck will be on my side for awhile now after screwing me.

 

good luck! man I feel for you, I had to run a tap in mine one time, scared the hell out of me! It cleaned up and all is well now

 

Next time I'm out in the garage I'll try to get a good pic of what I'm looking at. Just for a reference.

 

I can't help but think what a recipe for disaster this could be. Think of the carnage that can happen if the new short bolt backs out even a small amount....the damper could spin on the shaft, the timing gear could slide axially stressing the timing chain and chewing up the case. You really can't do this on a high performance engine......you have to get that bolt out or replace the crank. Welding it on will certainly keep those bad things from happening but guarantees angst when it's time to take something apart.

Perhaps you can get a bushing made at your local machine shop that will screw into the remaining threads and act as a centering device for your pilot drill. Once the pilot hole is drilled you can go up drill sizes without too much worry.

You really should fix it correctly, even if it is hard to do......

 

Apparently you haven't read his other threads.

 

I am going to try redrilling a bigger center hole this time. I will use a shorter length bolt as a last resort basically. There are plenty of threads left and it should hold well.

 

I have..hence my comments. I can imagine all sorts of disaster...4-1/2 turns rounds up to 5 and a thinner washer should be fine, etc,etc....

I wasn't arguing with you...I was just suggesting the OP go through the pain of doing a full fix.

 

It seems as though suggestions are being made that I have half assed fixes before coming from other threads with problems on my vehicle. I haven't, and if that isn't what the subtle comments are referencing then maybe they should be made more clear on meaning.

 

Don't sweat it...just speedy and me sparring...

 

Ok, well I got a new center hole drilled and it's deep if not all the way through the broken bolt. The extractor grabs good but I still can't manage to budge it. Eventually when it does move it just strips out. I lightly tap it with a hammer to dig it in more and it still wants to strip out. I don't want to risk breaking it off in the bolt I would be back to square one if I did that. So what now? Bigger extractor? Enlarge the center hole again?

 

Keep going larger and larger with the drill bits so you leave the smallest shell of the broken bolt. You usually want to use the latest extractor you can....