replacing a c-4 fuel filter and other maintenance


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the fuel filters located under the front pass side door area near the frame and the shop manual will go into some detail on its removal, yes your going to loose some fuel so its best to do this up on a lift or jack stands where access is easier and where you can see what your doing.
theres an arrow on the filter indicating direction of fuel flow for a reason , pay attention and do it correctly, have some shop towels and a fire extinguisher handy ANYTIME you work on fuel lines!
basically this is easy to do once you loosen the clamps (10MM bolts) and follow directions in the shop manual

Get your fuel level as low as possible,before you start work, elevate the front of the car as much as possible,to reduce the fuel tanks tendency to drain fuel, remove the fuel pump fuse, crank motor and let it run for a few seconds then shut it off to reduce fuel back pressure.
Don,t try this with a full tank!! keep a fire extinguisher very handy

don,t smoke!! or allow others who do near the car

Changing the fuel filter on a 1993 C4 (info from the net)

Tools required: you will need--at a minimum
a decent quality, floor jack, jack stands ,

(maybe wheel chocks)
if your only lifting the one side of the corvette for easy access
(ideally if your old, a mechanics creeper

and a SMOOTH & flat concrete floor,
and a good shop light helps, and a few paper towels and an oil drain pan,
to catch a bit of fuel that may drain,):facepalm::like:

16 mm and
13/16 inch open/box end wrenches, 13/16 socket, 10 mm open end wrench, 10
mm socket, safety goggles, latex gloves to keep the gas off your hands in
case you get to hold your lady that night, small to medium size hands, a
fire extinguisher close at hand, and finally, a lot of patience.

The fuel filter is
located along the frame rail on the right side of the car. This job could
best be accomplished with the car on a lift, but can be done with the car
on jack stands. I used the jack stands. The car should have less than
tank of gas.

Procedure: Loosen the fuel filler cap to relieve the
pressure from the tank. From this point on I wore safety goggles, not
safety glasses. Remove the right fuel rail cover. Place a rag under the
shrader valve where you would normally attach a fuel pressure gauge.
Remove the shrader valve dust cover and press the valve stem to relieve
the pressure on the fuel system. My car had not been started for two
weeks and the gas cap was left loose for several hours before I started.
About 4 tablespoons of gas came out of the shrader valve. Replace the
dust cap on the valve and the fuel rail cover. Tighten the fuel filler

I used a quartz work light under the car to see, but made sure
to keep it a distance from any gas or gas vapors. I opened the garage
door and turned on the ceiling fan. Remove the two screws that hold the
two fuel lines to the under side of the car using a 10 mm socket. These
are located along the right rocker panel and are the two screws located
closest to the fuel filter. This is necessary so that you can remove the
stainless steel tubing on the input side of the filter.

the strap that holds the fuel filter to the car frame using the 10 mm
open-end wrench. This screw was behind the return fuel line. I had to
wedge a socket extension between the frame and the return line in order
to have enough room (enough room is a relative term when working on a
Corvette) to remove the screw. Even then it was very tight quarters.
Remove the input fuel line from the filter by holding the filter with the
13/16-inch wrench and turning the nut on the fuel line with the 16 mm
wrench. On my car about 1 cup of gas ran out when I loosened this
connection. I caught it in a coffee can and a rag. Once it stopped
draining, I dumped the gas out of the can and placed the gas soaked rag
outside of the garage.

The top fuel line on the filter is another
story. I have heard that some remove the fuel line where it connects to
the fuel rail and pull the filter up and out of the engine compartment to
change the filter. I couldn,t figure out how to break the connection at
the fuel rail so I removed the line from the top of the filter. The
catalytic converter is in the way of the upper fuel filter connection. I
had to place the 16 mm open-end around one side of the cat closest to the
fuel filter, and then use my index finger of my right hand and hold the
wrench this way. My right hand was around the other side of the cat.
Since I was replacing the filter I didn,t care if I ruined the old filter.
I used a 13/16 socket on the bottom of the filter to loosen the filter
while holding the top fuel line with the 16 mm wrench. I ended up bending
the bottom fitting on the filter, but got the filter off of the top fuel

Inspect the o-rings on the two gas lines before installing
the new filter. New O-rings are not included with the new filter. Place
the filter on the top fuel line and reverse the procedure to tighten the
fuel lines to the new filter. Use care when turning the new filter with
the socket wrench so that you don,t bend the filter. One of the hardest
jobs was replacing the retaining strap around the new filter. I had to
wedge the return line out of the way and it still took me 15 minutes to
get the holding screw started into the frame of the car.

everything has been re-assembled and tightened, start the car and let it
run for 1-2 minutes. Shut off the engine and check for any fuel leaks.
This is very important as a leak could drop or spray fuel on the catalytic
converter and you would have a really hot set of wheels, no pun intended.
I repeated this staring procedure several times over the next several
hours to insure I had no leaks.
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how long has it been since you've replaced your corvette fuel filter?

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