I noticed that black crap from the gas/fuel line rubs off when you touch it. It appears that the fuel could be breaking the rubber down. I am not a mechanic by any means, so I was wondering if it's necessary to replace this hose, and maybe any other hoses since my truck is almost 4 years old.



Here's another line with cracks.



My new Tsunami battery terminals that I picked up from CC since my factory negative terminal was extremely corroded.

 

If you don't have fuel leaking out of the line's I wouldn't worry about it. The outer coating is just for protection, it doesn't seal the line.
Bryan

 

I can see your point, but wouldn't you want to catch a problem before it became a problem? I replaced the 1st pic with a new one to show my dirty finger. The fuel line is not dirty by any means, it just gets you dirty if you touch it. It's like something is breaking the rubber down.

What about the rubber line with cracks that runs into the upper intake?

 

Fuel will break down the rubber exterior of the line, I don't believe this is what's happening to your line's. Heat has probably broken down the protective coating on your line's, and that's what you're seeing!
Catching a problem prior to the problem is excellent!!!
Bryan

 

That is a vacuum line that has a insulating jacket over it...NO FUEL...

 

I have the same deal with the same line on my L. I don't think it's an issue worth worrying about.

 

If you're concerned, you can throw some Thermo-sleeve over them.

 

Clean your engine once in awhile and you want have that problem.

 

Thanks for the feedback guys.

You honestly think that has something to do with the problems listed in my original post?

 

first, the fuel would break down the interior of the hose.
second, it's "engineered" not to break down.
third, my '69 mustang has factory rubber lines on it that were in fine condition before I changed them.
fourth, That is probably dust from the supercharger belt. Rub your finger under the snout of the supercharger (behind where the pulley is) and I betcha it will be BLACK... that is the belt wearing away covering your engine with rubber. Clean it once in a while.

 

First of all that is not a "fuel line". All the fuel lines on these trucks are metal hardline. gotta agree with thye others its most likely belt wear dust and road grim. clean everything check it in a week or 2.

 

Not dust ...

I have the same problem ... That vacuum line is falling apart from
the outside in. It might be engine degreaser or cleaners that are doing it,
or maybe it's just too hot on the EGR side of the engine.

I am gonna replace mine with Silicon hose this year ... Tired of FILTHY
arms when I change the plugs.

 

Yea it's definitely not dirt/dust. I feel like a nub for not realizing the gas/fuel line is a vacuum line. :P I'll pick up some replacement hoses from the Ford parts house and replace them.

Thanks again for the replies.

 

Where can I get some of that?

 

http://www.thermotec.com/products/full/14005/14005.html
or
http://www.boostplanet.com/thermo_sleeve.htm


But I got mine from Jegs

http://www.jegs.com/webapp/wcs/store...tegoryId=16021