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Diesel Purging

Fuel injectors get clogged and dirty.  Running some undiluted Lubro Moly
Diesel Purge through the injectors can clean them and significantly reduce
rough idle, pinging/nailing, smoke output and also improve mileage.  It's a
good idea to "purge" your injectors about once a year.  Sometimes it's
hard to figure out which fuel lines to disconnect so take a good look at the
photos below before you start.

Here is what you're going to need:

A Jar
2 Fuel Line Clamps or Plugs
1 Can of Diesel Purge
15" of 1/4" Fuel Hose
1 Inline Fuel Filter
Rags

Overview:

You want the engine to run straight Purge through the injectors.  In order
to do this you have to disconnect the fuel supply line and immerse it into
your jar of Purge.  The fuel pump will then suck the Purge up and send it to the
injectors.  The injectors won't use all the Purge that is sent.  What they don't
use is returned to the fuel tank through the fuel return line.  You don't want
your expensive Purge going back to the fuel tank so we'll need to make sure
it goes back into your jar to be recycled.  To do this you simply disconnect
the fuel return line and immerse that into the jar of Purge.

This is the jar that I use:

It's a mayo jar with a large and small hole drilled in the top.

Here is the fuel return line.  The cloth fuel line (A) that comes from the injectors
attaches to the left knuckle on the main fuel filter housing.  It continues running
through a larger diameter hose back to the fuel tank.

Follow the return line down and remove it at point A (see red blotchy arrow).
Immerse this line into the big hole in the top of the Purge jar.  Plug the metal
line that leads back to the fuel tank.

Remove and plug/clamp the fuel supply line from the inline filter at point B.
Attach and new inline filter if you wish and then attach your length of 1/4"
fuel line to the inline filter at point B.  The other end of the 1/4" line goes
into the jar of Purge...through the small hole in the top.

Now you're ready to do the actual purging.  Make sure the lines are fully
immersed in the jar and keep them that way.  You don't want the system
to suck air.  Make sure the cooling fan is clear before you procede.
Prop the jar somwhere so it's reasonably stable.
Start the engine and quickly check to make sure nothing is leaking.
The 1/4" line will draw a bunch of the Purge out of the jar but the big
return hose will be furiously squirting it back in.  Again, make sure both hoses
are at the jar bottom.  Rev the engine at different speeds until most of the Purge
is gone.  It will take about 10 or 20 minutes.

Stop the engine when most of the Purge is gone.
Reconnect your lines and don't forget to tighten the clamps.
Pour the remainder of the Purge into your fuel tank.  Clean up any spilled
fuel with rags and lightly spray some water around where you've been working
to clean/dispurse any drips of fuel that may cause damage.  Periodically
check the fuel lines and connections for any leaks.

I love the smell of Lubro Moly Diesel Purge in the morning.
It smells like....victory.