Fuel Filter Replacement

[ajkolar]

Looking for some general help as I am getting ready to replace my fuel filter in a '98 Blazer 4 x 4.


Is there any special tools needed to replace the fuel filter?

How does the fuel filter get removed from the frame rail?

How do the fuel lines separate from both sides of the fuel filter?

I believe pulling the fuel pump fuse while running will depressurize the system, correct?

Thanks in advance.

[Chris Stewart]

[quote=ajkolar]Looking for some general help as I am getting ready to replace my fuel filter in a '98 Blazer 4 x 4.


Is there any special tools needed to replace the fuel filter?
I use some line wrenches to keep from slipping on the fittings...I forget what size and my '97 is gone, totalled
You can check the sizes with regular open end wrenches then you won't have to buy a whole set.

How does the fuel filter get removed from the frame rail?
It has a band that slides on the frame bracket and will slide off & on.

How do the fuel lines separate from both sides of the fuel filter?
The fuel line fittings screw off the filter fittings(nuts).

I believe pulling the fuel pump fuse while running will depressurize the system, correct?
Nope, the factory recommends opening the bleeder on a test kit. You can wait overnight then put a rag over the 1st fitting as you loosen it.

Disconnect the vehicle battery before starting work.

Be sure to wear eye protection, don't allow smoking or any other spark generation within 50ft of the car and all other safety precautions....yer messing with gasoline.

QUOTE]

[MT-2500]

You will need good tools.
A 5/8 brake line type wrench for line filtting and a metric 20 open end wrench or brake line wrench on filter nut.
If the line nut is froze/stuck to the line do not twist the fuel line.
Try to get the other end lose and spin filter to get it off of a stuck fuel line fitting.

Coat line nut and line with anti-seize to help remove it the next time.
MT

[ajkolar]

Just thought I would add a couple of things to this thread for those of you who are going to attempt this filter change and have never done it before (things I was a little confused about until after doing it). This all applies to a '98 4 x 4 blazer.

First, to depressurize the fuel system I pull the "ECM B" fuse while the truck was running which cut power to the fuel pump (and probably a few other things) and killed the vehicle. I then turned the engine over a couple times. I don't know if this is protocol, but worked great for me as there was no pressure when disconnecting the fuel lines.

The fuel filter is located in a rubber/plastic bracket mounted to the frame rail under the drivers side door area.

I loosed the fuel line closet to the back end of the vehicle (before losening the bracket) using a 20 mm open end wrench to keep the fuel filter in place, and then used a 16 mm wrech to losen the fuel line (5/8 will work as well I believe). A crescent wrench would work as well in place of the 20 mm open end wrench.

The fuel filter is located in a rubber/plastic bracket mounted to the frame rail under the drivers side door area. There is one small bolt that hold its to the frame rail (maybe 9/16 or so). After taking out the bolt, the braket is snapped onto three lines that pass above the fuel filter. Un snap the bracket from these lines ( by carefully pulling down on the bracket or using your thumb and forefineger to pop them out individuall). The bracket will still be on the fuel filter. There are then two tabs at the end of the fuel line fitting still connecting to the filter. Simply squeeze these two tabs (thumb and fore finger again) and pull this line off the fuel filter. Now use a pair of channel locks or something to squeeze the old fuel filter out of the plastic bracket.

Install in reverse.

[ajkolar]

By the way, after replacing the fuel filter my acceleration problem and lost power was restored. My MPG's on the highway jumped from 11 MPG back to 19-20 MPG where they should be...

[MT-2500]

Originally Posted by ajkolar

By the way, after replacing the fuel filter my acceleration problem and lost power was restored. My MPG's on the highway jumped from 11 MPG back to 19-20 MPG where they should be...

Thanks for posting back how it went.
That was a real big jump in mileage.
If the old filter ws real bad you might want to run some heat or gas treatment in it and recheck it after driving it a while.
Just goes to prove you can not shut the fuel off and get better mileage.
Good Luck
MT