So I thought I'd take advantage of the beautiful spring-like day to change the spark plugs in my '97 F250HD. I've been putting off doing this job since I got the truck in 2004. What could possible go wrong?

The first two came out with a fight. The third one busted off in the socket wrench. I thought it was just the porcelain but it broke off from the hex part up. So all that was left in the head was the threaded part and the electrode.

I knew I was now in for a mess, having to pull the head off to have the plug drilled out and dreaded that job, but it is one I could do myself, especially with some coaching from the experts on here. Now, stop laughing because it gets better.

I had to move the truck out of the way of my wife's car so I figured I could just start it and drive it the 20' I needed to, just on seven cylinders. It started right up but after about three seconds I hear a pop and then a rattle. I shut it right down and within a split second I realized what I had done.

I'm guessing the electrode dropped into the cylinder and was bouncing off the piston.....

So, several questions if I may.

1. What are the odds the piston isn't junked? I never took it above idle.
2. Is it worth pulling and rebuilding the motor on a 11 year-old truck. It is in great shape otherwise ('97 F250HD 5.8L auto)
3. Is it worth pulling the head and trying to visually inspect the piston and would it tell me anything?

There is a well respected motor rebuilder (Coburn Engines) not far from me that I have used before. I'm planning on talking to him tomorrow and may just bite the bullet and have him do the job soup to nuts. My fear is that once he starts pulling it there will be 100 little nickel and dime things to do "while we're at it".

4. What should a remove/rebuild/reinstall job like this cost without any major surprises?
5. What else should I do "while I'm at it"?

Thanks. I'm going to throw up now. Feel free to laugh by the way.

 

pull off the head to see what you have done.

then decide what to do.

i did not laugh at all.

 

If you dropped a broken spark plug in your cylinder, you are definitley looking at a cracked head along with a damaged piston. Depending on how many miles are on it, you could pull the oil pan and the head, unbolt the piston from the crank and replace the piston. You're still going to have to replace the head though. I would just go ahead a rebuild the motor, because with a new head and piston on 1 side you'll have compression differences. Are you sure that the spark plug fell in.

 

Are you sure its the electrode? Its held in the head with the same threads that held the spark plug in and I dont see how it could have fell in the cyld. Try to get a small stick or a pencil and see if it will go in the hole something definetly is not rite here and if it did fall in there I wuold think it could have done some damage. If you try to remove the rest of the plugs try running the engine a few min. to get it hot and maby the block will expand enough to help remove the plugs. Now if the electrode didnt fall and is still in the hole you might try removing it with an easy out go to the zone and buy you one that will fit .Before you try to remove it soak the the part left in the block real good with blaster. and let it soak for a few hours . When you replace the plugs put some antisieze on the threads and it wont happen agn. This is a good posting so keep in touch to let us know how it is going Good luck TREEY

 

I'm not positive but I'm guessing that is what the rattle was. I thought I heard something bang under the hood but it all happened so fast. It's probably wishful thinking that the electrode flew out instead of in.

I didn't even think of a busted head. You really think that would happen as opposed to a piston?

QL2 - my fear with just pulling the head for a look is that if it turns out to be worse than a stuck plug that I won't be able to get anyone to touch it. If it were summer I'd yank the motor myself but I can't do it in my garage (no clearance) and certainly don't want to attempt this in my driveway in the winter. Plus the truck is my emergency winter ride and don't really want to be without it any longer than I have to.

If I've grenaded the motor, who sells a good long block?

 

My buddy Brians dad accidentally dropped a small screw down in the piston chamder of his 66 mustang with a 289 in and didn't realize he had done it. He had to replace the piston and the head. That thing hits with so much force something as big as a broken spark plug would definitley crack the head. I seriously doubt though it went in, like tboss said stick a pencil or a thin rod in the head and see if you can freely move it, if not the plug is still in there.

 

wow, that sucks. I've messed up a few times too so I know how you feel. Much respect for being so light hearted about it. I would be crying myself to sleep like I did many times before.

Anyway, it's possible that your didn't do any damage even if the electrode dropped off. worse case scenario, you have to get a new head. If you think you're able to do the job go for it. Assess the damage and replace the parts as needed.

 

i still say pull the head.

if someone has to remove the motor they will not care if you took off a head and whatever else that needed to come off.

label everything for them or put it back together before getting a mechanic to pull the engine if needed.

 

I just went back out there with a flashlight and a mirror. I found the center electrode and some porcelain on the ground. I was able to look down into the hole where the plug used to be and I could see the side electrode still firmly in place. This makes me feel a little better except for the half inch or so piece of porcelain that should be around the center electrode but isn't.

How deep into the combustion chamber do these plugs extend? I'm hoping that maybe I got lucky and all of it shot out.

 

never know...maybe compression blew the electrode OUT, rather than such it in...now wouldn't that be nice

 

looks like you already thought of that...................

 

so is the broken part out or still in?

 

Broken plugs are a royal PITA. I would pull the head. Even a small chunk of metal or ceramic can imbed itself into a piston. I've seen valve heads driven into pistons. If you get the head off and don't have any damage at least you'll know for sure. Trying to extract the remains of a broken plug without dropping anything into the cylinder is dicey at best anyway.

 

I agree with you 100% that is the correct course of action. But, with the weather, the season and the fact that I am scheduled to deploy in March, I need to just get it done - don't really have the time to tinker with it.

I do have a couple bucks stashed away though. As much as I like working on vehicles, I may be better off long term to pay someone to do it.

If I was going to do something boneheaded like this, I sure wish I had done it in the spring or summer......

Now I'm going back outside (again) to look for that piece of porcelain....even though I think I know where it is.

 

Not sure yet. The only part of the plug unaccounted for is the piece of porcelain that went around the bottom of the center electrode. If I find this piece outside of the engine I may be better off than I thought.