Ronny g
North hollywood,#2Consumer Comment
Sun, October 31, 2010
Yeah, I have too much free time.
The problem is actually the timing chain guide..which is a nylon/plastic. The gears are metal unlike older non overhead cam engines which were sometimes nylon and didn't last forever either..but this is somewhat common. Seems complaints typically start at around 100,000 miles, and can be due to poor maintenance or heavy duty use.
According to other reports I read, all other reports told of "rattling" type noises coming from the front of the engine when the nylon would start to wear out.. there should have been some noise under load if you noticed which if checked you could have had this fixed before the motor was destroyed. Granted it is not a cheap fix unless you have the tools and skills to do it yourself, but it is less then replacing the engine for sure. Now you may wonder why they use plastic in the engine? Bear in mind it is a chain "guide"..not the gears itself..I copied the following information from a Ford truck forum that seems to really know these engines...I had the same type engine in a late Model Mustang and it was really a good engine. I never had a problem with it so I never had to tear the motor down. But it seems to be a known issue to some Ford owners with overhead cam engines.
To answer the question why anyone would build this stuff out of plastic??...
On overhead cam engines, the timing chains become very long. They won't hold tension by themselves, so they need a tensioner setup to take up the slack. So one side of the chain has a guide that the chain just rolls across, while the other side of the chain has a tensioner that has to push on the chain somehow. So the tensioner pushes on an aluminum guide, covered in plastic. It's not like it's China plastic toy plastic were talking about here. Im sure it's very good nylon, like Delrin or something. Probably is Delrin actually. (Dupont spent $50 million developing Delrin in the 1950's). But with constant metal chains sliding across it, eventually the plastic wears. Especially if the engine isn't maintained well.
I believe that the noise in my motor is most likely the timing chain tensioner arm (aluminum) rubbing against the timing chain, because parts of the plastic are worn off. A change in engine load probably slacks the chain up some, and causes it to ride in a spot where more plastic is, or at least not push on the aluminum as much.
Ford probably felt the value of OHC's outweighed the increased maintenance needs of the fancier timing chain setup. The rest of the motor is nearly bulletproof for stock.
Ronny g
North hollywood,#3Consumer Comment
Sun, October 31, 2010
What is the mileage?
Whatever it is you posted a picture of..it does seem to be a result of physical damage. But what is not clear, is if this was a result of shipping, or did something explode internally and break the chunk off of the valve cover?
It is well known in the industry that vehicles use nylon...or as some call it "plastic" for the timing chain gears (not just Ford), but I have not been able to find any information regarding an "engine cassette" other then your complaints. Are the engine components no longer under warranty? If not are you expecting Ford to warranty it anyhow?