I like the heating idea and if you can't get a torch on the plug you can heat a rod that fits the recess for better access. Heat rises so if the rod you heat is held at a vertical angle the heat will rise and heat the plug. I do not like the idea of using an impact tool and whacking the block... cast iron is brittle. I use an electric impact gun a lot and it works great.

Other possibility if a metric will not fit is take a piece of soup can IE thin metal and hold it over plug while you softly drive the allen into it. Soda can is too thin and aluminum, soup can may be tin. If you are using an allen key with the bent end, cut it off and use a small 6 pt socket the same size as the key and a socket wrench for a bit more leverage.

If all else fails as far as getting a bit on the plug, you might have enough room to thread it with a "bottoming" tap then screw a bolt into the thread and then a locking nut on the bolt. You thread the bolt until it bottoms out, tighten the nut against the plug, and keep your fingers crossed that all the work you did created enough heat to loosen it.

Heating the block and cooling the plug has worked also. You don't need all that much heat like maybe a propane torch or even a HD electric soldering iron but then the cooling part is either the allen key left in the ice box or soaked in DRY ICE.

I seldom have good luck with easy outs because as the easy out screws in it expands the plug. I have had good luck with left threaded drills. As the drill spins the same direction as removing the plug it could unscrew it.

Good luck.

 

 

My car had sat (with water in the block) for 15 years before I bought it and the drain plugs were rusted solid! Heating them was the ONLY thing that worked for me. Good luck.

 

Has the process been decided yet? If you are still considering and have not begun here are more thoughts.

If you do wish to drill and worried about missing center, start with a drill bit that will fit in the key hole without hitting the edges and use that just to center a point to drill then switch to a smaller bit until you hit the size you want, preferably the size for either the easy out or tap.

If you are going to use the "heat rises" way of heating the plug heat the rod before you place it on the plug to make it easier to concentrate the heat. If you put the rod on the plug cold then heat it the block will heat sink the heating process.

To avoid going too deep into the block and hurting a cylinder you can make a drill stop several ways. You can slide pipe or tubing over the bits and leave just a small amount of bit protruding. You can also use metal nuts stacked over the drill shaft with tape holding them from falling off.

If you are going to try using the Torx bit or allen key and will be going clear through, use the bit the same size as the core of the key. You may be able to drive the allen key shaft into fresh metal and form a bite, kind of like broaching it. If you do that you can use JB Weld on the key and lock it to the worn area of the plug before attempting removal.
If you do drill all the way through and find water you can use a wet or dry vac over the plug hole and blow air into the other side to help. It will be easier to heat the plug when water is not touching it.

Take little steps when removing material and as each one fails you can go to the next one. If you go all out the first attempt you can't back up.

 

If you use a drill use a cordless...

 

That plug looks to me like it may be brass....

 

Okay, braze a bolt in place. Or a Torx bit, or Allen bit, or..............

Still, my first choice is to just do nothing. If that plug doesn't ever come out again in the useful life of that engine, it won't hurt a thing.

 

Got it out. Ended up removing the side pipe which was a small adventure in itself since the mount near the exhaust exit was a rusted mess and the carriage bolt spun in the frame slot. With a clear shot at the plug I hammered in a T45 torx bit and then hit it with with a torch. Tried an impact driver but it didn't work - not much room to swing a hammer plus I didn't want to crack the block. Ended up applying lots of heat and using a 1/2" ratchet to get it out. It sure made a nasty metal on metal screech when it finally came out.




This is what I am replacing the internal hex plugs with


Thanks for all of the suggestions. Assuming I didn't crack the block, everything is back on track.

Brian

 

Run a 1/4" pipe tap into the threads to clean them, go easy. My suggestion is to get some plugs like the original (probably just steel) and use some permatex #2 on the threads and just snug them, that's all the tighter they need to be.

My brother has the same problem and you can't get a square bite with exhaust in place, very frustrating..It's important to drain the block when the antifreeze gets serviced.

 

Good job! It took you over 2 months but, as is said, better late than never.

Gary

 

Between work, family stuff, and other fix it stuff a few hours a months is all I can get. Before I had kids I would see stories about who guys got into projects and were finishing them 20 years later and not understand how that was possible. Now that I have kids and a demanding job I get it.............

Brian

 

Brian, where did you actually apply the heat?

 

Great job especially that the block survived. Thanks for the tip about the SS plug from Amazon. I ordering some tomorrow. On the engines that I drain often I use the same kind of drain the radiators have but they are not durable at twisting so I change them as soon as they look soft. Also, these are tapered and the tighter the less likely they well back out so I put Never Seize on them rather than sealer and it's easier to get out next time. Never had one leak or fall out.

 

On the plug and all around the plug careful not to burn the oil pan gasket. I sprayed it a few times with penetrating oil. It didn't get that hot because of the coolant behind the block.
Brian

 

I understand, just teasing.

Gary

 

Heat the plug with a propane torch till hot. Let it cool till completely cold. It may take overnight. Us a Snap ON easy out that is a spiral type. Do not us any other kind but a SnAp ON. Make sure the tool is not bottomed and use a long wrench to turn. It out. Be careful as you may only have one chance .Have done this at least 50 times and got Every one out. Dave

 

Here's another vote for "leave it alone, it's not bothering anybody." In 40+ years of changing antifreeze, I've never taken out the block drain plugs. Nothing noticeable went bad because of this.

 

Guess you guys missed post # 28. He got it out.

Gary

 

Did you ever get the plug free from the Torx bit?

 

No reason to drain the block I never have just drain the radiator and refill a couple of times during the year if your worried about getting it all changed, or this could end up ugly just my opinion.