Old gaskets are sticking as hell to surface and from cast iron as engine block easy to remove but what is the best way to get them off from alloy parts. You cant scratch with something sharp and make marks in the alloy so what is the best way to do it.

 

wire brush. wire brush on a drill for faster removal.

 

Gasket remover spray/foam and a Permatex Safer Scraper. If you use a wire brush with drill, use a fine wire that's not super aggressive.

 

They make plastic scrappers that look just like straight razors and fit into the same holder. Got to use a scrapper that's softer than the material your scrapping to prevent damage.

 

 

 

Most of the time it is just patience........... grasshopper. Just realize it's not going to come off in 20 seconds and take your time

 

Well, the older gasket remover (methylene chloride) worked. Last automotive gasket remover (name brand) I bought worked a little bit. So if you've still got some old paint remover (pre-Obama), give that a try. Otherwise patience, some kind of softener stuff/solvent, and a single edge razor blade scraper. Careful! Don't scratch or gouge. I would not use Scotchbrite (research/readup on it) or any other abrasive (unless last ditch and with very great care. My $0.02.

 

This. The real mechanics at "Big Evil Red Oil Services Company" used them. Some also used those eraser disk thingys like you'd use to remove decals.
If you have a lot to do I guess. I opt for old fashioned sharp razor, oil/solvent, and time consuming patience.

 

The issue with the eraser disc is that the old gasket material gets thrown around to who knows where and could end up in the cooling system ports or even the oil system where they find their way into the oil pump screen.