OK to attach an engine pull chain device to the headbolt holes of a bare block? I need to move block from stand to my truck and was thinking to attach the four chains to each corner using head bolts.

We have done it tons of times. In the past.

Now we use old serpentine belts through the cylinders. The local speed shop seen me do it that way and now that is the way they move their blocks.

Most salvage yards have many just laying around and will let you scrounge a few for nothing.

I do that all the time with a 3/8 chain

easiest way is flip it upside down, put the center main cap on and use a old v-belt through the cap.

Brian

Anyone ever asks to bolt to head bolt holes on block to lift it...just say no. :-(

Why?
Or are you saying with the heads on the block to not use the head bolts?
If so, I agree

You guys using old V-belts or serpentines are....let's say, brave.
If they'll break driving a fan & alternator...no thanks.
I use seat belt webbing if a chain won't work.
I'd prefer accessory/bell housing threads to head bolt threads, but I've used the carb-mount plates on my SB motors (which isn't what the OP was asking).
Pretty much depends on the task at hand.

Seat belts are okay in certain circumstances. But how much experience do you have lifting with serpentine belts? Sounds like none.

I have seen engines lifted with them for years and years. As long as the belts are in good shape, it's all good. We have also used them to pull stuck mowers and many other things. When we have overloaded them pulling something more than we should have with them, we are always surprised just how much they would pull before failure.

For a serpentine belt in good shape, lifting an engine is no problem. Done it and seen it done dozens and dozens of times.

If you have reservations with them, don't use them. But real world experience with them does count for something.

You are correct, sir: absolutely zero experience with that.
To me, a "used drive belt" means its strength is compromised, and it was replaced rather than risk failure.
Glad it works - so far - for those who use that method, though.

Wherever possible, the fastener (bolt, stud) should only be loaded in shear (90° to its length), not tension.
I would never use an accessory belt.
Bare block: seat belts through the bores, wrapped around a 6" piece of 2 × 4 wood below the bores.

I'm going to make an engine sling out of my old outdated belts. They should be plenty strong enough.

Gus

We move bare blocks around the shop all day long with old fan belts around the main caps. A bare block is only a couple hundred pounds. If you rig up a fan belt in a pull rig it will hold a few thousand pounds before it breaks. The fibers inside a fan belt are super strong in tension.

Not at all. As I mentioned earlier, the salvage yards are full of belts that were fully serviceable when the vehicle was killed. A simple close examination will reveal it's condition. Same as with a chain or anything else you would lift with.

No one is trying to convince you to use anything other than what you are currently using. You are only looking for reasons to support your decision not to use belts while ignoring many, many real experiences with them.

Carry on.

Jeez, Dave, feeling argumentative ? Superior ?
I'm not ignoring or justifying anything, merely stating my preference and why.
On some things, I don't want to take a chance; maybe that's paranoid and ignorant, but I'm cautious about some things.
Like swinging 600 lbs over my cars' fenders.
For just moving stuff around, the drive belt thing is pretty clever.
Have a nice day.

Accessory belts' service life is based on continuous tension, with minimal start-up torque load (cranking).
Seat belts are designed to accept huge instant torque loads (no G force = no torque).

If you use an accessory belt, don't let the weight bounce ("take up the slack") when lifting.

Neither argumentative nor superior. Just correcting your erroneous assumption that the belts must have been worn out when removed from service. You would want to know the truth, wouldn't you?

And you are the only one to bring up "swinging 600 lbs over my cars' fenders". Jeez!