Sorta OT: any tips on removing a stubborn set screw other than drilling it out?

[1320stang]

This isn't on a car, but could be.

I'm doing a engine swap on a lawn mower and I'm trying to remove a drive pulley off a shaft (bad engine) to put onto another shaft (good engine) so I can put it on the selfpropelled mower.

The set screw uses an 1/8" allen wrench and the pulley appears to be steel.

I've tried:

1. brute force

2. tightening before loosening

3. penetrating oil (PB blaster)

4. hitting the inside bottom of the set screw with a punch to loosen it up

5. heat (propane torch)

6. heat and brute force

7. heat and penetrating oil

8. heat and candle wax

9. heat and carb cleaner on the set screw (thermal shock)

10. different combinations of the above

At this point, my only option may be to drill it out, which I'd rather not do, just looking if there is an option I haven't yet thought of.

 

[86bluecobra]

can you weld a nut onto it? It always works for me when I bust a bolt off. The extreme heat seems to free it up.

 

[C6AE]

Is it stripped, or just stuck?

 

[Hack]

Propane never loosened anything for me. I recommend MAPP gas. You can get it in the same small hand torch size as a bottle of propane, but the bottle is yellow.

If necessary, get a heat shield. Hardware stores have kevlar blankets in the plumbing areas. They work great for keeping the heat localized.

If the set screw doesn't come out easily, heat it more.

 

[1320stang]

can you weld a nut onto it? It always works for me when I bust a bolt off. The extreme heat seems to free it up.

No, it's down inside the pulley shaft, in other words, the top doesn't stick out.

Is it stripped, or just stuck?

I don't think it's stripped, I think it's just stuck. It's on a Craftsman 3-in-1 mower and I'll be it's been on there since the factory put it on. No signs of ever have any tool marks on it.

Propane never loosened anything for me. I recommend MAPP gas. You can get it in the same small hand torch size as a bottle of propane, but the bottle is yellow.

If necessary, get a heat shield. Hardware stores have kevlar blankets in the plumbing areas. They work great for keeping the heat localized.

If the set screw doesn't come out easily, heat it more.

I have been waiting for this bottle to run out, then I'll get MAPP gas. I don't understand what a heat shield would do for me, the engine is pulled, sitting on the deck of my trailer and I can get to the shaft easy enough. My next thought would be toe heat it to a dull cherry red, then spray some carb cleaner or brake cleaner in the set screw hole, maybe I just don't have enough thermal shock. Other than that, drilling might be the best way.