5.4L 3V Catastrophic engine failure
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5.4L 3V Catastrophic engine failure
My 2004 F-150 with 95XXX miles died last week. Was driving home from work when I had sudden loss of power and a CLANGING noise coming from the motor.
I got the truck home, pulled valve covers and discovered broken rocker and no valve on cylinder 3. Started the process of pulling the motor, and dropped the oil pan and could see the bottom of the head through the hole in the piston in cylinder 3.... lots of metal in pan.
Anyway, from what I can tell the timing belt tensioner on that side failed, allowed the chain to become QUITE loose, and the motor went out of time and caused a valve to contact a piston. All in all, pretty bad damage.
Even more scary, there where no warning signs, and the truck was maintained religiously by a mechanic (me).
However, I picked up a BRAND NEW 08 5.4L 3v for 1700 bucks and have it in the truck already. Just gotta hook up wiring and hoses. Hopefully I get more than 95XXX miles this time.
I got the truck home, pulled valve covers and discovered broken rocker and no valve on cylinder 3. Started the process of pulling the motor, and dropped the oil pan and could see the bottom of the head through the hole in the piston in cylinder 3.... lots of metal in pan.
Anyway, from what I can tell the timing belt tensioner on that side failed, allowed the chain to become QUITE loose, and the motor went out of time and caused a valve to contact a piston. All in all, pretty bad damage.
Even more scary, there where no warning signs, and the truck was maintained religiously by a mechanic (me).
However, I picked up a BRAND NEW 08 5.4L 3v for 1700 bucks and have it in the truck already. Just gotta hook up wiring and hoses. Hopefully I get more than 95XXX miles this time.
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From: whaleyville, MD
what kind of oil did you use. the chain tensioner is hyd. and works from oil pressure. and what do you mean by you could see the bottom of the head? did it throw out the whole piston or something? what exactly could you see that happened?
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naa, there's a yellow piece of plastic that the timing chain runs along side of, that was not there on the offending side of the motor. This caused the chain to be very loose.
About the piston, I meant I could see through the large hole in the piston up to the head. I was looking from the oilpan up past the crank.
Always just used motorcraft 5w20 and a motorcraft filter.
About the piston, I meant I could see through the large hole in the piston up to the head. I was looking from the oilpan up past the crank.
Always just used motorcraft 5w20 and a motorcraft filter.
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never heard of it. I'm convinced it's an isolated incident related to the failure of a single part. *im hoping*
