Broken Valve Spring

[Andrew Homar]

I own a 2004 Sport Trac. Recently, with the engine at idle and the trans. in the Park position, just before I was about to turn the vehicle off, the engine started to run rough and I heard an intermittant tapping from the upper front of the engine. Removal of the valve cover revealed a broken valve spring. I was wondering if any other members had experienced a similar problem with their V-6 4.0 liter engine? Any information would be greatly appreciated. Thanks. Andrew.

 

[Tom Schindler]

First I have heard of it.





Tom

 

[Travis Munday]

A while back someone else had a broken valve spring. How many miles on the motor? Maybe its just a bad batch of valve springs.

 

[Aaron Yarbough]

It seems like I can recall only 1 other repoted incident. More than likely it's 1 defect out of who knows how many thousand of valve springs that were made. Unfortunately, it happens......

 

[Greg Stuhlsatz]

That is odd.:unsure:

 

[Aaron Yarbough]

That is odd.

But it happens.....

 

[Richard L]

Modern valve springs are about as good as they get. Its very rare to break a valve spring unless you are racing and running at maximum rpm for extended periods of time. Almost impossible to do on a street vehicle driven at reasonable speeds, but it does happen.



...Rich

 

[Bill Ellis]

Just like all man made items, some will break. Valve spring breaking is very rare but will happen to somebody, sometime. Hope there was no piston damage. Replace spring and if it runs OK, then it's OK.

 

[Todd Z]

I have broken Valve springs from over revving the engine, detonation, or floating the valves.



As others have said, they can just be a defective part and let go....



Todd Z

 

[John Barnes]

I had one break at 70 MPH on my 2002 with 21000 miles. The spring came through the rocker cover.

 

[Richard L]

Mountaintrac,

If it came throught the valvecover, it sounds more like you broke a valve shpring keeper..



...Rich