Broken spark plug head removal help?

[WREKS]

Use a left handed drill bit. Might unscrew itself while drilling. John

I like that because the heat from drilling can break the corrosion lock on the threads, especially with a little penetrating fluid.

 

[Cobra Jet Steering LLC]

You do not want particles dropping in the combustion chamber, here is the trick I would use a large EZ out and a old fashion impact driver or a drill driver with a socket attached to the ez out

 

[Jores]

Ok- when you do get it out use a dab of anti-seize on the new plug threads and when you tighten them don't use a torque wrench or you might get them in to tight- the aluminum heads like a little anti-seize. On my boat at the ten hour service I removed the plugs and used the anti-seize and just reinstalled them. John

 

[Jores]

To use an easy out you still have to drill a hole- use a left hand drill bit for this and you might not have to use an easy out ( if you break an easy out you will need to pull the head because they are so hard)

 

[Cobra Jet Steering LLC]

The plug breaks off leaving the hollow threaded section so the hole is already there, the ez out is very hard and very strong I like the hand held impact driver because you are actually turning the body of it and then striking the end with a heavy hammer all the time keeping a twisting pressure on the impact driver, you can instantly feel when the part you are removing comes loose, the taper of the ez out body will not allow a broken part to fall through But I would be surprised if you can break one doing it the way I said. I removed one from a Kawasaki ultra 250 years ago and that plug was even thinner than the plugs Yamaha uses I still did not need to drill anything , Do your best to avoid getting anything down in the combustion chamber if possible and when you do get the plug out get with me and I will share how to clean the cylinder of any minute particles that could cause issues if they are left in there.

 

[Murf'n'surf]

Search head removal and broken spark plug

https://jetboaters.net/threads/well-sh-t-spark-plug-fail.27911/

 

[Antman]

Well one more stuck plug ,listen once you get the piece out I have a way to insure you do not have any residual trash or debris left in the cylinder that could harm the rings etc. if you heat the broken plug part and remove it using the correct type of easy out you will be able to do it without removing the head. Just let me know when you get the broken plug piece out. I will pm you how to clean the cylinder out

I'm in the same situation. 1st and 3rd plugs on port engine, starboard engine was fine, was able to remove partial of the 1st plug without drilling because the insulator came out whole, but only 3/4 of the broken piece removed. Any and all help much appreciated.

 

[Cobra Jet Steering LLC]

hmmmm Now you see why I put a small amount of never seize on my plugs day one before they ever see the water, just changed a set with 250 hours on them no problem and dielectric grease on the inside of the boot as well. So put some oil or transmission fluid in the cylinder maybe an inch deep then place a plastic tube down in the cylinder and I use an air gun that has a suction hose to draw out the oil with the particles in it but you can get by using a wet vac just be ready to have to clean it real good when you finish . tape a round piece of wood etc in the end of the vac hose with the plastic tube in the middle so the suction goes through the hose, also use as large a diameter hose as the plug hole will allow and move it as much as possible to go around the edges of the top of the piston. If you use an air compressor and a air suction gun hook a hose to the end of the gun and have it blow the oil into a 5 gallon can preferably with the top on and the hose in the opening . Either way if you can draw out the oil you will get out the trash and you can do it twice to be sure you cleaned it all out. and the good news is even if you do it several times you will only have to clean the mess up ONCE!

 

[Cambo]

If your plugs seem tight like they frozen you may want to try an impact wrench. Probably not the best place to post as most people searching may have broken them already. So why the impact wrench, while looking at a used boat that had been sitting for a few years the owner could not get the motor to turn over so I offered to pull the plugs to see if we could get the impeller to turn. The plug in #3 was stuck I told him I didn't want to force it he recommended the impact gun. He came back with his sons cordless hi torque Ryobi impact driver I started on setting one nothing, went to setting two still nothing then went to setting three and it was slowly moving. I Let it go a few turns then tried the regular socket with ratchet it was still too tight to go by hand, so back to the impact driver and it slowly came out. The ratchet must apply pressure in a different way that causes the plug to snap. As Jeff stated above, I agree with using anti seize my choice is copper anti seize over 25 years not one stuck plug .

 

[Cobra Jet Steering LLC]

One other method is to STOP trying to unscrew it and spray WD40 or similar penetrating oil in the hole where the the plug is then turn the plug back down and then up and repeat this forward and reverse process to work the stuck plug out each time you move it back down the oil gets deeper in the threads, Think of using a tap to thread a hole if it starts to bind you go backward and then forward until you finish if not you snap the tap in the hole and have a big mess . since the plugs are down in a recess that holds the oil directly on the threads of the plug.

 

[Maslin]

With the top "flat" broken off the threads are no longer under any tension, any stuck they have now is just in the threads. A good soak, some heat and a left hand bit/extractor set could do it. You don't want anything to fall into the cylinder, metal is easy to remove with a magnet, ceramic is tough.

Be careful with anti-seize on plug threads. Torque specs are set for dry plugs, you can do real damage over torquing a steel plug into an aluminum head with grease on the threads. Some manufacturers specifically state not to grease the threads, NGK comes to mind.

One of my guys swore by removing stuck glow plugs with a 1/4" impact. He would run the engine to full temp and dive in, the 1/4" gun probably isn't strong enough to break anything and the impact shakes them out.

 

[lazergeek]

With the top "flat" broken off the threads are no longer under any tension, any stuck they have now is just in the threads. A good soak, some heat and a left hand bit/extractor set could do it. You don't want anything to fall into the cylinder, metal is easy to remove with a magnet, ceramic is tough.

Be careful with anti-seize on plug threads. Torque specs are set for dry plugs, you can do real damage over torquing a steel plug into an aluminum head with grease on the threads. Some manufacturers specifically state not to grease the threads, NGK comes to mind.

One of my guys swore by removing stuck glow plugs with a 1/4" impact. He would run the engine to full temp and dive in, the 1/4" gun probably isn't strong enough to break anything and the impact shakes them out.

Aluminum Head and steel spark plug causes galvanic corrosion. This is more of an issue causing broken plugs then over torqueing. NGK's so called coating that they claim does not require anti seize is BS. After having a plug seize and break because of corrosion with only 50 hours in a yamaha factory instaleld plug. $1200 later from dealer removing the head to remove the stub, I will ALWAYS use anti seize now. Easy out with impact driver would not get it to budge.

 

[ascendedshogn]

Well one more stuck plug ,listen once you get the piece out I have a way to insure you do not have any residual trash or debris left in the cylinder that could harm the rings etc. if you heat the broken plug part and remove it using the correct type of easy out you will be able to do it without removing the head. Just let me know when you get the broken plug piece out. I will pm you how to clean the cylinder out

I have this exact scenario. Could you pm me your method?