4.6 launched plug3 but....
Thread Starter
|
Member
Joined: Apr 2011
Posts: 14
Likes: 0
From: wv
4.6 launched plug3 but....
About 2 months ago plug3 blew out of the cylinder and took the cops with it.
I got the truck home and managed to get a plug to grab a few threads and it lasted until a week or so ago, when the same thing happened again. AN awful noise and a few miles later I got it back home and tried a new plug (lost the old one with the launch), but could not get the threads to catch.
Picked up a plug threader tool and tried to cut some new threads, but the plug hole seems to loose to cut anything that would grab. That is the easy part to take care of with a reamer and insert, however when hand cranking the engine to get #3 at TDC, I noticed the piston is NOT MOVING and think its more than just a plug blowout. Piston seems stuck at TDC.
I stopped doing anything else on the engine as I paid a lot for a 3 year extended warranty on the truck, which only has 85K on it. Pistons, rods, bearing ect are all covered, but these warranty things always seem to look for a reason for them not to authorize the repairs.
I also stopped by our local Ford dealer this week to discuss what happened and their engine guy is out until next week, so I'll have to have a rollback come by and take it down to them next week. They will analyze and advise on the issue and get the skinny from the warranty folks.
Its strange that I don't hear anything knocking about when the engine is started. Sounds just like it missing a plug only with no sounds of a rotating assembly noise.
Ordered a bore scope yesterday, so I can see whats going on in the cylinder. What was different with this blow out from the first one was I could hear a tick and misfire about 10 seconds before the plug blew.
I got the truck home and managed to get a plug to grab a few threads and it lasted until a week or so ago, when the same thing happened again. AN awful noise and a few miles later I got it back home and tried a new plug (lost the old one with the launch), but could not get the threads to catch.
Picked up a plug threader tool and tried to cut some new threads, but the plug hole seems to loose to cut anything that would grab. That is the easy part to take care of with a reamer and insert, however when hand cranking the engine to get #3 at TDC, I noticed the piston is NOT MOVING and think its more than just a plug blowout. Piston seems stuck at TDC.
I stopped doing anything else on the engine as I paid a lot for a 3 year extended warranty on the truck, which only has 85K on it. Pistons, rods, bearing ect are all covered, but these warranty things always seem to look for a reason for them not to authorize the repairs.
I also stopped by our local Ford dealer this week to discuss what happened and their engine guy is out until next week, so I'll have to have a rollback come by and take it down to them next week. They will analyze and advise on the issue and get the skinny from the warranty folks.
Its strange that I don't hear anything knocking about when the engine is started. Sounds just like it missing a plug only with no sounds of a rotating assembly noise.
Ordered a bore scope yesterday, so I can see whats going on in the cylinder. What was different with this blow out from the first one was I could hear a tick and misfire about 10 seconds before the plug blew.
Technical Article Contributor
Joined: Apr 2009
Posts: 10,697
Likes: 14
From: In the fast lane from LA to Tokyo...
Contact "Galaxy" he's a member on here.....he rents out a kit called "time sert".....its the only way to fix blown plugs with the exception of a new head.....
Thread Starter
|
Member
Joined: Apr 2011
Posts: 14
Likes: 0
From: wv
Well here is an update:
#3 is moving so my CYL prode must have been getting hung up due to the angle that it was positioned at.
Today ,since I could not let this go, I used a short piece of straight fuel line as a probe ,because nothing made sense with out hearing some sort of knocking noise from the engine...and indeed the cylinder is fine.
I did a little reaming with a thread kit and managed to get a short 4 thread insert to grab and a decent amount of torqe on the plug to get it homed.
Reparied the COPS with JB on the mount and the nipple,put heavy thread lock on the plug and insert,checked existing codes on #3 (misfire, lean condition)and cleared those. Fired it up and monitored data real time and it seems to be fixed for now.
To bad Ford has not addresses this problem on 5.4 and 4.6 engines as it is all too prevelent. Guess a TSB recall would cost a lot of $$$$ to timesert
plug holes.
Also I dont think this is covered under any waranty.
#3 is moving so my CYL prode must have been getting hung up due to the angle that it was positioned at.
Today ,since I could not let this go, I used a short piece of straight fuel line as a probe ,because nothing made sense with out hearing some sort of knocking noise from the engine...and indeed the cylinder is fine.
I did a little reaming with a thread kit and managed to get a short 4 thread insert to grab and a decent amount of torqe on the plug to get it homed.
Reparied the COPS with JB on the mount and the nipple,put heavy thread lock on the plug and insert,checked existing codes on #3 (misfire, lean condition)and cleared those. Fired it up and monitored data real time and it seems to be fixed for now.
To bad Ford has not addresses this problem on 5.4 and 4.6 engines as it is all too prevelent. Guess a TSB recall would cost a lot of $$$$ to timesert
plug holes.
Also I dont think this is covered under any waranty.
Senior Member
Joined: Aug 2010
Posts: 453
Likes: 0
From: Mesa, AZ
Its ok you can ream out the heli-coil when it fails like I had too... Mine backed out VERY slowly and eventually far enough to cause a low grade misfire. Hopefully you didn't void the warranty by doing that.