I’m rebuilding a motor to drop into my truck (using one hand, as I’ve got a broken arm). I got ripped off when buying it, and ended up with a rusty hunk instead of what was advertised. I got down to the harmonic balancer, used the belt trick to get the bolt off, and then busted out my crank pulley puller set. The harmonic balancer was so rusted that all the holes used for pulling except ONE had lost their threads. I went for it, and realized that only one side of the pulley was being pulled. I used a pry bar to straighten it out during the process. Near the end, I heard a crack, and it turns out I cracked the pulley right where it enters the engine. I continued, and I suppose I bottomed out and the pulley wasn’t coming any further… I snapped the head of the pulley removal tool bolt right off. So, I tried using vice grips to loosen the broken bolt, but the pulley is cracked in such a way that it creates friction against the engine block and stops me from loosening it. Uh-oh. The pulley must be close to coming out, but I’m really not sure what to do. I now realize that I don’t believe I put the pointed cone piece on the tip of the pulley removal bolt, not sure if that had something to do with my dilemma. Help Please… Thank you
If it were me I would rethread the balancer holes to the next size up. As for the tool, either replace the bolt or maybe use an AutoZone rental tool. With the pull being canted it becomes a problem.
If rust is an issue you might use of those small plumber’s torches to apply some heat to it. Heat will expand the metal and crack any rust loose. I do tend to think that rust is not the issue though.
Ok, I got the broken balancer and tool out finally, thanks to lots of PB blaster, an angle grinder, and plenty of struggling. Not exactly in that order, PB blasters flamable. As the broken bolt was close to coming out, it stopped loosening as I twisted. I got it out, but I stripped the threads on the inside of the crank. About 1/2 inch of non-existent threads. Soooo… If I rethread the crank, will those new threads be strong enough? The destroyed threads start about 1/2 an inch into the crank hole. And do I rethread those threads to the same size? Thanks for the help.
I think that you will need to rethread it to the next size up with a bottoming tap. A 1/2" stripped out is quite a lot and the last thing you want once back together is to have the balancer loose or to come loose once back in operation. That will wallow the nose off of the crankshaft and if that happens you only have 2 options.
Weld the balancer to the crank which means no more access to the crank seal or front cover.
Replace the crankshaft which will be expensive and time consuming.
Hope that helps and good luck; and yes large size taps can be a bit pricy. I do not know what thread pitch is involved with this but you might check into something called C-Sert. Pricy but there’s not many alternatives.
I think I would try and find another crankshaft.