My machinist put in the 3 pipe plugs at the back of my engine block, and used some sort of weird epoxy/sealer junk on them. It's yellow, and quite hard. I can barely mark it with a fingernail, not teflon sealant, and not RTV, probably some variety of epoxy.

So far i've tried to remove these plugs with my folding allen key set, but I only managed to bend the entire housing of the key set.
I bought a 1/4" allen key with 3/8" socket drive, and removed 1 plug. The other 2 i'm starting to round, because i'm reefing on it so hard.

I was going to use my impact gun, but I figured i'd check here first, 'cuz I really don't want to be drilling these out soon. Anyone know what that goop is? Maybe a chemical I can use to dissolve it first?

Thanks

 

ok, destroyed one with the impact gun.

looked like red in the threads for the one I removed, so I tried heating up one, and removing it... Well, that's the one I destroyed.

any ideas?

 

try heat on the area around the plugs.

 

Yup, lots and lots of heat.

 

Heat it up and melt a candle on the threads. The wax will 'wick' up into the threads and lubricate.

For the heat, a little propane torch may or may not work. Its best to use a oxy-acetelene, that gets alot hotter.

 

I *was* using a baby butane torch... those suck...
k, i'll borrow the propane torch from work. I can't really get wax onto the thread 'cuz the epoxy is covering the outside...

I'll try heating up the area around it then.

oh, some 5/16" ready rod worked well to remove the front plug, after I removed this one pipe plug. So far so good...

 

It's probably an anerobic sealer/thread locker. The machine shop assembler did not want any chance of the plugs leaking. Propane or MAPP should be adequate, but the whole casting will get fairly warm.

My "favorites" are the older square recess plugs. I see those and just skip everything and go for the drill...