Square Drain Plugs in Block - How do you remove them?

A Big Ass Hammer

The plugs in the water jacket are likely rusted into the block after 40 years. You may wish to try some heat from a oxygen/acetylene torch in combination with penetrating oil, but there is the danger that you could crack the block and that would ruin your whole day.

It might be best to drill them out and retap the threads.

Either way it is a job that requires considerable skill, not something for the novice.

Here's a trick I think I will try....

Dear Rocky,


I am rebuilding an engine again. I had the same problem with the block plugs, too. I tried everything short of an acetylene torch and the AERA parafin trick. I admitted defeat and had the machine shop remove the things with the rest of the machine operations. Good luck. Let us know if it works.

Warmest regards, Chuck Engles

sounds like a good ideal.

we use to use paraffin in a similair way to remove nuts from studs.