Blown 5.4 ???
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Blown 5.4 ???
OK HERE IS MY QUESTION/SITUATION... I HAVE A 97 EXPY WITH THE 5.4 WHICH NOW HAS 155,000 MILES. AT 149,000 WHILE IT WAS RUNNING GREAT I TOOK OFF FROM A LIGHT AND IT SUDDENLY STARTED MAKING A LOUD SOUND WHICH I KNEW WAS PROBABLY A SPARK PLUG WHICH HAD CAME OUT. I HAD THE TRUCK TOWED HOME AND UPON LOOKING FURTHER IT WAS THE RIGHT REAR PLUG. IT LOOKED AS IF SOMEONE HAD HIT IT WITH A HAMMER. IT CAME OUT SO HARD THAT IT ALSO BROKE THE COIL OFF OF THE VALVE COVER. WELL I FIGURED THAT THE MOTOR HAD SOME SERIOUS PROBLEMS SO I REPLACED IT. I FIGURED FROM THE LOOKS OF THE PLUG THAT I HAD BROKEN A VALVE OR SOMETHING ELSE MAJOR. WELL I REPLACED THE MOTOR AND I STARTED TO TEAR INTO THE OLD ONE OUT OF CURIOSITY. SO FAR I HAVE REMOVED THE ENTIRE RIGHT HEAD AND EVERYTHING LOOKS GOOD,NO BROKEN OR DAMAGED VALVES. I WAS TOLD THAT THE CONNECTING ROD MAY OF STREATCHED BUT I SEE NO DAMAGE ON THE TOP OF THE PISTON WHERE IT MAY OF CONTACTED THE PLUG,CAUSING THE DAMAGE AND FORCING IT OUT OF THE HEAD. I WILL EVENTUALY TEAR INTO IT FURTHER BUT FIGURED I WOULD SEE OF ANYONNE ELSE MAY HAVE HAD A SIMILAR SITUATION.
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Joined: May 2002
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From: Annapolis, Maryland
There's been a lot of discussion about spark plugs being blown out of these heads for a variety of reasons - I think the consensus is that some of the threading was just a wee bit too large, so the plug fit in there somewhat loose. After a couple hundred thousand miles of heat and pressure - BAM!
Ford recommends having the plugs removed and inspected at (I think) around 50,000 miles. Now, there is so much work involved in removing the plugs, the only thing I can think of is that it's an excuse to have the plugs re-torqued. That's the only plausible explanation - why go through all the work to remove them and put the old plugs back when you can buy new plugs for maybe $25-50. Might as well replace them while you're in there, right?
I'm going to move this thread to the 4.6/5.4 Modular V8 Forum - I think they'll be able to help a bit more on a question this specific.
Please let us know how it turns out, though - I'm curious to see what happens.
Best of luck!
XXL
Ford recommends having the plugs removed and inspected at (I think) around 50,000 miles. Now, there is so much work involved in removing the plugs, the only thing I can think of is that it's an excuse to have the plugs re-torqued. That's the only plausible explanation - why go through all the work to remove them and put the old plugs back when you can buy new plugs for maybe $25-50. Might as well replace them while you're in there, right?
I'm going to move this thread to the 4.6/5.4 Modular V8 Forum - I think they'll be able to help a bit more on a question this specific.
Please let us know how it turns out, though - I'm curious to see what happens.
Best of luck!
XXL
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BIGMATTXXL,
AT FIRST THAT IS WHAT I THOUGHT HAD HAPPENED. I THOUGHT ONE OF THE PLUGS HAD JUST WORKED ITS WAY LOOSE AND CAME OUT OF THE HEAD BUT THE SEVERE DAMAGE TO THE PLUG ITSELF ALONG WITH IT BREAKING THE COIL OFF OF THE VALVE COVER IS WHAT LED ME TO BELIEVE THAT IT WAS SOMETHING MAJOR.
AT FIRST THAT IS WHAT I THOUGHT HAD HAPPENED. I THOUGHT ONE OF THE PLUGS HAD JUST WORKED ITS WAY LOOSE AND CAME OUT OF THE HEAD BUT THE SEVERE DAMAGE TO THE PLUG ITSELF ALONG WITH IT BREAKING THE COIL OFF OF THE VALVE COVER IS WHAT LED ME TO BELIEVE THAT IT WAS SOMETHING MAJOR.
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Joined: Jul 2003
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From: Kansas
brooks35,
Welcome to the forum. As a new user I trust you weren't aware that using all caps is considered "yelling"...obviously a simple misunderstanding. Regarding the plug...if you scroll through this
forum or enter "spark plug" in the search box you'll readily find that a blown plug is common on this engine. In fact, scroll down to the post from Mav 74 regarding a blown plug. You'll read from the responses that inserts have often been used for the repair...
Here's a site frequently referred to for the helicoil insert: http://www.timesert.com./
Fortunately, I haven't had this problem with my 99 EXPY, but I did have a plug blow out on my 69 SS396 Chevelle...shattered the plug as it blew out with such force...sure made a heck of a noise when it let go!
Hope this info is of some help...
Welcome to the forum. As a new user I trust you weren't aware that using all caps is considered "yelling"...obviously a simple misunderstanding. Regarding the plug...if you scroll through this
forum or enter "spark plug" in the search box you'll readily find that a blown plug is common on this engine. In fact, scroll down to the post from Mav 74 regarding a blown plug. You'll read from the responses that inserts have often been used for the repair...
Here's a site frequently referred to for the helicoil insert: http://www.timesert.com./
Fortunately, I haven't had this problem with my 99 EXPY, but I did have a plug blow out on my 69 SS396 Chevelle...shattered the plug as it blew out with such force...sure made a heck of a noise when it let go!
Hope this info is of some help...
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Opps sorry for yelling guys,i wasn't aware of that.....thanks for letting me know. As far as the plug issue the only thing that led me to beleive it was something major is the actual damage to the plug and that it actually broke the coil off of the valve cover when it came out. Is this normal? The electrode part of the plug was so severly damaged i would of swore something struck it knocking it out of the cylinder head. I hope i didn't go through all the trouble of a new motor for nothing!!! I will say this, I was totally impressed with the condition of the motor overall for having almost 150,000 miles on it. When i tore it down there wasn't even a ridge on the cylinder wall. But what a severe pain in the a** replacing a motor in the expy. I spoke with a friend that works for Ford after i did it and he said that they actually pull the body off the frame to swap the motor. I believe it would of been easier after doing it the old fashion way.
