I just had a Ford dealership rebuild my 2001 Lightning Engine because the lower bearings went out. They actually put in a new crank, bearings and all the usuals, but they also had to bore out one cylinder because it was scarred and put in an oversized piston. They only put in one and it was number 4.

When I picked it up it was idling rough. They said it would take time for the computer to reset. That sounded reasonable so I left. It kept idiling rough and then the CEL came on. It indicated that I needed to change the TPS and the EGR, so I did it. It did not really change anthing. I kept going through the diagnostics of the troubles but nothing made it any better.

Well about 3000 miles into my bad experience I was racing a 2001 Cobra on the street, which I beat quite handily, and after I let off the gas it started running unbearibly rough. The tone from the exhaust changed, it would not idle at all under load it would buck, chug, and misfire like crazy. It would however idle just fine if I just had it parked. The CEL came on flashing indicating that a cylinder was misfiring. It was number 4. I grabbed a new coil pack and spark plug to change them thinking that was the trouble. I pulled the sparkplug to find the tip bent down and layers of carbon. Thinking the sparkplug melted or something I replaced it with a new one.

After I replaced the plug it idled fine and would even go through the higher revs sitting in my garage, but it did that when the other plug was bad too, so I drove it to see if it was better, and it seemed to be worse.

I then pulled back into the garge and pulled the plug to see that it was also bent over, but it looked like something beat the crap out of it too. I then called the dealer that rebuilt it and had it towed to them for diagnostics.

They said that I had dropped something, like a bolt, into the cylinder and that caused the piston to fail. It did not matter what was wrong before to them because they are looking for a way out I guess.

I KNOW that I did not drop anyhting into there, so I am perplexed as to what could have happened to the number 4 cylinder. There was evidense of something in beating up the cylinder and head, but the piston was also destroyed around the outside edge almost as if it were grinding against the wall and breaking up.

Does anyone know if one piston oversized would cause it to fail like this? Has this happened to anyone else? What could the possible causes be?

Thanks,

Bill

 

you better go to that dealer and start bitchin..... it sounds like they are trying to pull a fast one on you!!!!!!!!!!

 

Is it standard practice to bore out one cylinder and put in just one oversized piston? I would think that the engine balance would be thrown all out of whack when you did something like that. I think your service people are inept. I would take it to a different dealer and explain it to them.
Jes

 

I have never heard of anyone putting one oversized piston in a motor. What idiotai's. Yes, it would throw off the balance of the motor.

 

Wow... I don't even think that "Primitive Pete" would bore just one cylilnder on a block... I would get all the 'work order receipts' together and go to another dealer.
I would think that some Service Managers talk to one another, so I would just try to remember that ya' catch more flies w/ honey, not vineager... 'cuz I know I'd be real pissed about now...
Good Luck!

 

Could that failure be related to that? Would the piston "self destruct" once a new plug was placed in there if it suddenly began to spark because the other one was ruined and not firing?

I guess I would like to know that it was nothing I did, but something that could have been caused by them....

Thanks for your responses....

 

Make sure you Document Everything! Record times of conversations and take pics if possible of that cylinder.

Good luck

Lew

 

It is common practice to overbore just one cylinder in low reving applications such as diesels. I have been a mechanic in the army 9 years and seen this many times. However I would not recommend this for engines such as the L that rev over 5 grand. Just not very good Idea. They should have over bored them all and went with oversized pistons. They went the cheaper route and you got the short end of the stick. If something was dropped in there you would have known it on the intial fire up. it would have been extremly loud if it was a bolt like they said and with it being an aluminum head would have sevely damaged it quickly. Stay on these guys and make them replace the entire engine.
At this point I would not entertain anymore repairs to your current engine. Hope everything works out for the best

Eric

 

Why would you bore a diesel? Most of them have liner's, just pull out the affected area install new liner.??
Bryan

 

most of the bigger diesel applications do have liners and yes we replace the liners. We have more hummers than anything and they do not have liners so it is mostly done on the hummers.

 

Look and see if the valve seat has came out.

It could have not had the proper piston to cylinder wall clearance
and it would seize up when it got hot. The piston would expand fastter then the block would. When you raced the truck the piston top would get real hot and would expand fastter. That is why the top of the piston is smaller than the rest of it.

Lean can cause it to do that also. I have also seen some lift the top off of the piston.

Does the engine have a rod knocking because that would let the piston come in contact with the head.

I would say that you have a clearance problem or a lean problem.

 

How did you know your bearings were bad? What kind of noise did it make? My 2001 is making a rough bearing noise.

 

The bearing noise was apparent when the engine would run at about 2500 RPM. The knocking (a solid knock, not a lifter sound) became very loud. It was barely noticeable at idle and higher RPMs.

 

Mine only does it at idle.

 

sounds like ur getting a new engine for christmas. Im no mechanic but i can totally agree with what people are sayin, over boreing one cylinder out of 8 = engine imbalancement. I'd work on getting a new engine, and if they dont co-opperate find a lawyer dude, cause if that engine is fixed, it will only have more and more problems as time passes. My $.02