[Blk 76]

I have a suborn/stuck pipe plug in my 455 engine head that goes into the water jacket and I've tried a wrench with a extension on it and it has started to strip the square hole. So I am thinking of using a die grinder or dremel tool with a rotary file in it to cut a groove in the side of of the plug down to just where the threads start and then try to collapse it just enough to be able to turn it. Any other ideas? I need this hole/port for a vacuum fitting that's controlled by the water inside the head. How tall are these pipe plugs from top to bottom? I believe it is a 1/2 inch pipe plug.

[NBF823]

hit that thing with a lot of PBS blaster, let it soak.

You could try slotting it, but I think your only best bet is to drill it and drive an easy out into the hole and turn it that way.

Lots of PB blaster, or your preferred rust penetrant. Remember that easy outs are sacrificial, so don't be afraid to grind it, and drill that hole so as the easy out fits just right.

Don't break the easy out - if you see the easy starting to twist, get it outta there, drill a bigger hole, use a larger easy and more penetrant. Those puppies are hardened and next to impossible to drill through.

Get comfortable, and be patient, it could take a while to get it out

[b-man]

I would definitely soak it with the PB Blaster or Kroil.

Then I would grind a junk 1/2" extension to fit the square hole in the plug, grind it to be a taper fit so you can pound it in with a hammer for a very tight fit.

Next use an air impact to slowly hammer it loose. Apply some heat to the head with a torch around the plug before you start.

Drilling it would be my last resort. Using an easy-out is very risky, once you break it off (you most likely will) you're screwed.

If you do get out the drill get it right on center so you can drill out almost the entire plug except the threads. At that point the threads should be fairly easy to either pick out or they will come out when chased with a 1/2-NPT pipe tap.

[mbwicz1]

I like b-mans idea, especially using heat. Easy-outs are really tough on a pipe plug, because they expand to get a bite, which can make the tight fit worse.

If that doesnt work, you can always try and drill out the center and tap for a smaller pipe plug. Unless you are going for a points-type resto, you can see if a 1/4 NPT plug will fit (it will likely have to be a 3/8 npt). Then you can use hardware store brass fittings to get to your vacuum fitting. It will be a fight to get the drill in there (with the square hole), but it is another option.

Good luck,
Mike

[Blk 76]

Do these usually come loose ok? Someone told me that you can break a chunk out of the head. I have sprayed it down with PB blaster and will do so several times before doing anything else. I think I will try the impact wrench with the extension driven in.

[65blackplate]

heat is your friend and the pb blaster too

[Schurkey]

In MY garage, that pipe plug would get heated cherry-red, allowed to cool, whereupon it would probably unthread easily.

Heat the PLUG, not the head. Heat expands the plug, but also makes it somewhat pliable. Plug cannot grow bigger around--so it squeezes out lengthwise instead. Once it cools, the diameter shrinks a few thousandths and relieves pressure on the threads. Plug may or may not be re-usable.

You can dump the head in a bucket of penetrating oil, if the threads are sealing air-tight, the oil can't get in there to do any good.

A decent impact wrench will most likely destroy the tool before the plug turns.

HEAT IS YOUR FRIEND.

[Blk 76]

I have a small hand propane torch will this work ok? How much heat is safe without the risk of damaging the head or gaskets?

[Schurkey]

Originally Posted by Blk 76

I have a small hand propane torch will this work ok? How much heat is safe without the risk of damaging the head or gaskets?

Not enough. You'll need an oxy-acetylene torch.

[gtofreek]

I agree with Schurkey here. Only I heat the plug until it's cherry red then squirt oil on it and around the threads. It will smoke and may catch on fire, Just blow it out, no big deal. When you squirt oil on it, the plug instantly shrinks and sucks the oil into the threads and the plug usually unscrews right out. Plug need to get red hot, and don't bother heating the head itself, just the plug. If you don't have access to oxy/acetylene, take it to a machine shop, I'm sure they can get it out for a few bucks.

[Sirrotica]

The gas wrench (torch) is the easiest and quickest way to remove anything like this because the heat will break down the oxidation along with shrinking when it cools. 40+ years working in maintenance, on cars, and road service on equipment, and I have found nothing better than heat to remove rusted parts. Hitting the part with a hammer to shock it would be second on my list to get stubborn parts to move. Striking a part will actually get the threads to straighten themselves out and conform to the other half of the threaded parts along with breaking the bond of corrosion.

Anyone that is going to be seriously involved in the car hobby should invest in an oxy/ acetylene torch set, it will make your work much easier and save you time and money in the long run.

[Blk 76]

I do not have the acetylene torch set so will it hurt to try the small propane torch? I have heard that the pipe plug needs to be heated and I have heard that the area around the plug needs heated, is one better than the other? How much heat is safe without damage to engine or gaskets?

[65blackplate]

if u want to try the mapp gas cylinder they will fit on a propane torch head u can get them at most hardware stores much hotter than propane (great for brake lines) might take a little longer to heat that head up though!

[gtofreek]

Originally Posted by 65blackplate

if u want to try the mapp gas cylinder they will fit on a propane torch head u can get them at most hardware stores much hotter than propane (great for brake lines) might take a little longer to heat that head up though!

They do screw onto propane torch heads but if you want the extra heat from the MAP gas, you need a map gas torch head. They meter the gas

[gtofreek]

Originally Posted by Blk 76

I do not have the acetylene torch set so will it hurt to try the small propane torch? I have heard that the pipe plug needs to be heated and I have heard that the area around the plug needs heated, is one better than the other? How much heat is safe without damage to engine or gaskets?

You have to heat the plug itself. Don't waste your time heating around the plug. I have removed thousands of oil galley plugs and have tried different ways of heating, and by far the best method has been heating the plug until red hot and squirt oil or WD-40 on it. The plug will instantly shrink, suck oil into the threads and break itself loose from the threads. You won't get it hot enough to hurt anything as long as you heat the plug itself.

[Sirrotica]

Your never going to hurt anything on a cast cylinder head by heating it to remove the plug. The gaskets are going to be fine as has already been mentioned heating it cherry red is not going to hurt a thing. A propane torch is probably not going to get it hot enough to break the corrosion bond, but you can give it a try. The hammering on it may do more good than the heat to free it up if you can't get someone with real torches to heat it.

[hurryinhoosier62]

Dittos on the heat! The plug has to be red hot if you are planning to remove it. Once it has been heated and penetrating lube is applied, it should come right out.

[Blk 76]

I do have the Mapp gas and torch for it so I guess I will give it a try.

[sts]

Good luck at finding a inverted square drive because they haven't made them for years. They quit making them in inverted square drive because the amount of required torque to remove them exceeds the fastener's abilty to maintain its integrity.

I drilled mine out to about 9/16", then used a small knife like file to cut 4 slots inside of the drill hole. Nex, I used a baby bhf and a cold chisel to cripple the metal inwards.

I just so happen to have a half dozen brandy new ones. Everyone says that they are avaible everwhere. If so, I'd like to see some pictures of new ones.

[michael j]

As said before heat the plug up then take a candle of some kind and touch it to
the heated plug. The heat will draw down wax and lubricate the threads, works better
I think than blaster etc. Just my thought. Mike