SOS Mercury mark 5 boat motor

called an easyout. i believe.

http://www.amazon.com/piece-Easy-Scr.../dp/B0002UJNWE

Originally Posted by PartTimeScrapper

called an easyout. i believe.

http://www.amazon.com/piece-Easy-Scr.../dp/B0002UJNWE

Easy outs are for removing broken screws, you have to drill a hole dead center then drive in the easy out. The twist is reversed so that when your using a wrench of it they tend to burrow deeper into the hole you drilled.

Still no guarantee the broken screw is going to come out, these tools require a bit of expertise in their use.

If you had used the impact driver from the start, nine times out of ten the screw or nut comes loose a bit of penetrating oil helps, failing that some heat on the bolt before it is broken off.

Your allowed 2 percent iron and still be good for clean aluminum.

The problem with iron screws used in aluminum is that they're dissimilar metals a natural electrolysis takes place that holds the screw firm. This is one of the reasons you find zinc anodes affixed to motors and other marine gear, these are sacrificial. Meaning that the electromotive series of metals, zinc give itself up sooner than the aluminum saving the engine from eroding away to nothing.

Still you have the iron screw problem, the iron wants to give way to the aluminum, electrolysis at work. Save yourself some grief sell the motor as dirty aluminum..