Straightening dent in crank pulley

So I have an aluminum crank pulley for my 86 (yup, more timing related stuff yay!). I got a big discount on it because it fell off a shelf and has a small dent in it. I was told heating it and straightening it was possible. What kind of torch and what procedure is best?

Tell whomever fed you that line to show you how to fix it......

Where is the bend? If it's somewhere that contacts the belt, you have a nice piece of scrap aluminum. If it's not, why bend it more?

It's probably equal in weight to 30 or more beer cans.

If just the outer flanges are bent, which is what usually happens when these things drop, you can ignore it, it's little more than a cosmetic problem.

If the entire pulley is bent you've got a serious problem, or maybe a piece of scrap aluminum, on your hands.

In reply to GameboyRMH:

Just the outer flange. Everything else is straight.

In that case, if it's bent away from the belt/barely bent, just leave it.

Here are pics of the pulley in question:

I don't think heat will help, if you're set on trying to use it I'd bend it out with pliers and see what happens.

The problem I've found with heating aluminum is that it goes "Not enough, not enough, not enough, liquid." Now, you could anneal that thing with a torch and a sharpie marker, then beat it back to position. It will likely harden up again on its own. Or you could just whack it. Put it on something flat, get something else flat to put on that bend, whap the something else. You will probably bend it back into about the right shape, or close enough to work.

Adjustable wrench adjusted so it's just the right width, then very slowly work your way across the bend.

In reply to mazdeuce:

No heat?

I wouldn't bother. It's either already work hardened enough that it will snap or it's not and it'll go back. There are just too many other variables in messing with a temper on a critical part like that.

Time to put on a movie and fiddle with my pulley I guess

Aluminum doesn't go to a plastic state like iron does. Iron goes to a plastic state that you can bend it and everything is great. Aluminum goes from solid to liquid, as I stated. You can anneal it and work it easier (it won't snap when you try to bend it) and that's about as good as it gets. If it was mine, I would try to anneal it. Put a mark on it with a black sharpie marker. Heat the mark until it just changes colors, let it cool, bend it. Or tap it with a 2x4 end on a flat plate, like I said.

In reply to Dr. Hess:

What would you use for heat? I have a butane torch or a propane/map one.

The MAP torch would probably be enough. I use an acetylene torch with a rose bud myself when annealing aluminum panels. You have to be REAL careful to avoid that darn liquid state. With the MAP torch, it wouldn't be so touchy, I don't think. Again, you have to watch for the color of the Sharpie mark to just change (gets lighter in color) and that's the right temp. Stop then. Tricky with protective eye glasses on.

I would place the face of the pulley on a flat surface like a steel plate or aluminum. Then take a piece of brass or aluminum and a hammer and using the plate as an anvil, hammer on the lip until it's resting on the plate the pulley is sitting on. I wouldn't bother with heat as your libel to mess the part up more than it already is.

Work it from the edges a little at a time. You want to ease it back into place.

Yeah, that's too pointy. Even a block of wood would work, though.

In reply to Dr. Hess:

Have plenty of those laying around.

I think you want something that will spread the force evenly. Using an adjustible wrench trying to bend it, I don't know, but supporting it with a flat surface, and something else flat to knock it straighter, I could see that working well. I would not be confident enough in my ability to heat and work aluminum to try heat.

This may very well be a dumb idea...

What about just cutting the bent portion of the flange off?

The belt is ribbed, and if the alignment of the pulley is good, the flange doesn't really do anything anyway. A small portion missing would have very little impact on the pulley's function. Balance could be an issue.

I agree with the flat surface and spreading the load, but I would warm the area with a heat gun to give it a little help. No danger of melting it that way. Don't cut that bent section off.

It's probably just common 6061, so malleability depends on the temper.
If you tap on it with a screwdriver shank, does it ring, or go thud?
I'm betting it's pretty soft, maybe T3, based on how the flange bent from the drop.
It's a light piece, so a fall off the shelf is not that much force.
I'd try to bend that flange back out of the way to give clearance to the belt.
If it snaps off, problem solved, dress the edges smooth.
Maybe then grind off an equal amount on the opposite side for balance.