I noticed a while back when I replaced the oil cooler on my 2000 Ex that I couldn't remove the block plugs. The one by the oil filter I thought was coming right out, but it was only half of the plug. The inner half was still in place not moving, so I just reinstalled the half and moved to the starter side. That one didn't want to budge with reasonable force so I just left them alone and went on to change the cooler.
That was about a year ago and I figured I'd have to get back to the plugs eventually. That time has come. I'm noticing coolant leaking from both plugs. I'm hoping someone has some good ideas on how to remove those, knowing one is broken off several threads in and I expect the other to be similar given the outward appearance. I didn't see anything in the tech folder that addressed the issue. Any thoughts? I definitely want to deal with this before my drip becomes a river.

 

My guess is plug was not broken, there was gunk caked up behind it in the block.

I often have to jam something in the hole to clear it out.

The other plug will come out with a strong enough tool.

 

Jason, I thought that might be the case at the time, so I tried jamming a bit with a screwdriver. No luck. Then I looked at the piece that came out and only had about two threads. So I'm pretty well positive it's broken.

 

That's going to be a chore, how accessible is it? Do you have a good shot at it and room to work?

 

That's going to be the key here in a successful repair - being able to get to it. My approach would be (if the remaining plug is below flush) get a set of transfer punches so you can locate dead center of the hole and redrill and tap the hole. I would only recommend if you have some machining experience though, must be precise as the naked eye/hand can get. If you don't have a straight shot at it, then... tough call. How much below flush is it? Liquid steel?

 

Pretty good access I suppose. Just remove the starter on the one side. I may get the motorcraft orings and replace the dorman ones on the oil cooler while I'm at it. Been less than a year and they are leaking again. I thought I read (after I used the dorman) where someone said use the motorcraft for that.

 

The next question I have and someone else here might know the answer is...how much heat can the block take in the vicinity of that? The only experience I had that even comes close to this was a spark plug in my S-15 Jimmy. When I took the plug out the threads around the plug rusted through and I was left with the threads in the hole and no nut. It was a do or junk the vehicle mission. I found a large easy out at Lowe's that fit the hole and was able to get it out. I figure you'll need to drill through that plug and put an easy out in it. If you can heat the block you can pretty much bank on it coming out but if you can't you're looking at drilling and tapping, as indicated above you'll need to get your hole centered for that and it won't be easy.

 

I was wondering about the heat issue also.

 

The hole for the ease out does not have to be drilled dead center. But a hole in the middle of the plug and if the ease out does not get it, put some heat on the surrounding surface while trying to turn the ease out. If that doesn't work, cut some slits from the drilled hole toward the outer edges without getting into the block threads.

 

I would not go over 300*F. Hot enough to curl bacon, but not burn it. Timing is more important than the amount of heat. Do you have an IR thermometer? Or access to one? If I was really going to try it, I would buy a bit of dry ice, drill the hole and make sure the ease out would start grabbing. Get the ease out of the way and pack that recessed area with dry ice, Then start heating the area around the plug. The greater the temperature difference between the two metals the greater the distance they wish to be away from each other. But I would not do any of this with a fire extinguisher at arms length.

 

I may not know trucks, but heat transfer is a different story. I would think, if this plug has coolant on the other side, you will be hard pressed to get it hot enough to help the threads loosen or to do any damage to the block. Can the coolant be removed another way to allow some heat to build in the metal?
What material is the plug? Might some pb blaster help with what may be a rusted plug? I have never pulled a block plug, but I have wrestled a couple of rusty bolts in my time. It always amazed me what a little penetrating oil can do... And I hear it helps with rusty bolts, too.

 

You raise a good point on the water on the other side of the plug, for some reason I was thinking that it would all drain out but now I'm thinking that the plugs wouldn't be necessary if that was the case. After drilling the hole removal of the water would be necessary, just add to the complexity of the situation. While I agree that it would be a novel idea if it worked, I don't see how dry ice is going to help, by the time the block is heated the dry ice will be sublimed out of there. Definitely soak it up with PB Blaster or Kroil for a week first. And it might even just come out without heat, provided that your luck is better than mine.

 

When you drill, be sure and use a left (counter clockwise)turning drill bit. Sometimes it will catch and unscrew what your drilling out.

 

JSpex, you've got some great info going on here for sure. In my opinion only, If it were me, I would start by first removing the antifreeze at the radiator drain plug. Then also remove the passenger side lower radiator hose as this will just about empty the system. You will have maybe about 1/2 gln +/- left in that side of the block that will drain out when you do finally remove the plug thats above the starter. Now focusing on the plug that's above the Starter. I'm thinking also and this is just my opinion here on what I would try first. I know these plugs are a real pain to remove because I recently went thru it. Soak it real good with a penetrating oil as mentioned above. Then take a blunt center punch so as not to hit the side walls and damage the walls of the plug, hit the inside of the plug several times to break the threads free. Taking in to consideration the size of the plug, your not unloading on the plug, just enough to where you feel it may have broke the threads free. It may take several attempts at this. Make sure to clean out the plug real well so that the Hex bit sits down in to the full depth inside the plug, take a hammer and tap the hex bit in to ensure that its completely seated at the bottom. At this point in my removal process I put a 3/8 to 1/2 reducer on a breaker bar in order to break it loose and in order to maintain control of the Hex bit as you start to torque on it. This worked for me.
Option 2. was to remove the freeze plug that sits just above the plug and soak it from the inside with penetrating oil and let it soak in and reattempt the plug removal process as mentioned above.
Option 3. Would have been to use a map gas bottle to (lightly) heat up the plug to remove it. Not the block, but concentrating the heat on the Plug.
As mentioned above by a couple of the guys, worse case scenario is drilling and tapping, and it my experience, this does not sound like a very difficult task at all.
Just a couple of ideas on how I got this stubborn plug removed from my block.
After removing the plug I installed these plugs with Teflon, and just snugged it up.
1/4" Hex plug.

 

JSpex, I just went through this with my radiator flush. Those plugs are a pin in the ars to remove. The one that gave me the most grief was the passenger side above the starter. I probably worked on that thing for an hour at least. It's not the most ideal location. I used some blaster on it, and let it soak, and I cleaned all the rusty material from around it using a wire brush, and a pick. I then tapped on the plug with a ball peen hammer. I kept using this technique until I was able to get it loose using a 1/4 drive ratchet. I was about to remove the starter even though I didn't want to. But that might be the only way to really get some leverage on it and give you some more clearance to work. The plug that's broke, you might be able to get an easy out in there and twist that guy out. Keep us posted.