Harmonic balancer bolt

[nonstop]

As said earlier, these were run for years with a pressed on balancer. While it might be a little unnerving, I wouldn't see it as a deal breaker. I would run it and just watch it. If it really bothers you, then fix it once the house is done. As for the cause, my guess would be that the balancer was installed using the bolt to drag the balancer in, instead of using a balancer installation tool.

[Caminuvik]

Nonstop, thanks for the new information, I had no idea that there were special tools for balancer installation. I have been guilty of installing the damper using the bolt. I didn't install this one, but makes sense of why it broke/stripped.
Got my building insulation inspection today, "good to cover", have a couple of days to clean out shop before drywall arrives. Will attempt to remove bolt, do leak down test on cylinder (regardless of bolt issue) and see where to go from there. If cylinder/valve holds pressure I will be a happy camper.
Again thanks to all for advice and support

[Shady Rascal]

Let's take a second and analyze this.

For all we know, that bolt might have been stripped out for decades. You just now discovered it though. What would have happened if you hadn't discovered it ? Nothing. Why are you jumping to action now ? Just use the flywheel to turn the engine over and leave that balancer bolt alone.

New guy Peter posted a perfect response up above but no one seemed to acknowledge it .

[Caminuvik]

Shady, you are correct, I guess the thing is if I find something broken I have this tendency to want it fixed. What happens if it did come off, catastrophic disaster, or are you just parked beside the road? Tried the magnetic, will try a larger one today. Winch broke on quad, yesterday at finish of plowing, and loh and behold it's snowing again this morning. All plowing vehicles down now, and still a week to spring. LOL
The motor has been rebuilt, supposed to have only 40,000 km. I guess I need to see what damage is to cylinder #2, if it holds compression, then worry (or not) about the damper bolt. Too many things on the plate and I don't juggle as well as I did a few years ago.
Thanks
Cam

[Shady Rascal]

Peter S is correct. The SBC didn't use a bolt for a lot of years. Even my 74 model six cylinder doesn't have a bolt from the factory. Harmonic balancers fit snugly. If you're not spinning one up to a lot of revs, it's not likely to migrate off.

Why not keep an eye on it ? Every time you fill it with gas just pop the hood and shine a flashlight down there to make sure it's not migrating outwards. My money says if you let sleeping dogs lie that it won't ever be a problem. It hasn't been so far has it ?

[tucsonjwt]

My 83 C20 454 had the bolt holes on the crank pulley shear off twice. After the second replacement I guessed that the harmonic balancer was the problem. The balancer did not shear off with the crank pulley, but it was the cause of the crank pulley working off the bolts.

I used the proper Loctite for the crank pulley and used grade 8 bolts after the new balancer was in place. So far so good.

So, in my experience, it is best not to overlook any problems you might have with the balancer.

Disclaimer: I know almost nothing about auto/truck repairs. The value of the above advice is worth approximately $.02.