Injector Fuel Lines

[mBdrvr]

My original fuel lines are connected to a rebuilt FIP. I thought I'd turn over the engine with the starter and the injectors disconnected to clean the lines out and confirm fuel flow. I put cups under the ends of the lines to see what happens. One line did not allow fuel to pass; the others eventually dripped fuel into the cups.

I removed the offending line and inserted a pipe cleaner for a few inches on either end and reinstalled. The fuel now moves through the line like the others but I'm concerned that the lines may have some debris that may clog my new injectors.

Two questions:

Is the fuel supposed to be at high pressure at the injectors on the intake stroke? I just get drips of seemingly equal pressure from all of them.

Is there a way to clean the insides of the lines or should I just spring for new lines from MB?

[CCollum]

Black Forest LLC will clean and plate them. I just had mine done. They are still finishing the pump rebuild, so I can't yet tell you how they are, but Michael there said a bunch of crap came out of the lines. You ought to give him a call. It's a standard service they offer. In fact, in his mind cleaning out the lines is important to do when redoing the pump. So I had them do both at the same time.

[stickandrudderman]

It is a service item to periodically run very high pressure cleaning agent (usually diesel) through the pipes to clean them.

[mBdrvr]

Thanks for the info.

What pressure should I see at the FIP outlets? The fuel dribbles out while cranking. Is that normal or should it be higher pressure?

[Benz Dr.]

IP moves very little fuel at idle or cranking speed so a small squirt is normal. At the very least I blow through the lines with compressed air which easily shows if they're free or not.

[Tyler S]

The fuel will dribble out when no injectors are installed. The injectors also act like check valves for the lines themselves. If the line is open then no pressure will build. The amount of fuel delivered by the IP is very small.

[mBdrvr]

Thanks again for the help.

I'm going to take the lines to a local fuel injection shop who say they can clean them out.

Paul

[ja17]

Fuel output at idle speed is very small as previously mentioned. The position of the IP linkage lever and rpms increases fuel output at higher speeds. Push the IP linkage lever all the way open if you would like more fuel output.

[mBdrvr]

Thanks for the information Joe.

[Pawel66]

Maybe I can add that I came across the issue of clogged fuel lines after plating. The plating Co should return them perfectly free inside, but you may want to double check before installation.