Mercedes-Benz Forum banner
1 - 20 of 30 Posts

·
Registered
Current 2017 GLE350, 2007 S550, 2002 S430, 1998 ML320 Deceased 74 240D, 92 400E, 97 E420, 13 GLK350
Joined
·
1,969 Posts
Discussion Starter · #1 · (Edited)
Last weekend, I replaced my fuel filter my S430 with 64k miles. Since I found only marginal descriptions on the forum on how to do the removal and replacement, decided to post the results. One post indicated a dealership charging $200 for this job.

DISCLAIMER – This write up is intended to be a ‘blog’ account of my changing the fuel filter on a 2002 S430 Mercedes. Nothing contained herein is intended to be a substitute for sound mechanical practices, or for OEM workshop instructions. I am not liable to anyone performing these steps as written. In other words, I'm not in any way at fault or to blame if you spontaneously combust or even just get a hangnail after reading this.

Tools used
1) Bosch Fuel Filter (AutohausAZ.com varies by model around $40)
2) Assortment of stainless steel hose clamps (two 7/16 and one ½ inch). Did not have to be rated for fuel injection pressure since this is all on the low side of the pump.
3) Extra fuel hose (contingency for splicing)
4) Phillips head and Standard Screw drivers
5) 10 mm socket, extension, and ratchet.
6) Nitrile Gloves (just don’t like gas soaked hands)
7) Safety Glasses
8) Inspection Mirror
9) Golf Tee. Yes, a wooden Golf Tee.
10) Garden shear, hand size. Really.
11) Inspection Mirror
12) Drain Pan
13) Jack stand.
14) Hydraulic jack and two 2x4 wood chocks
 

Attachments

·
Registered
Current 2017 GLE350, 2007 S550, 2002 S430, 1998 ML320 Deceased 74 240D, 92 400E, 97 E420, 13 GLK350
Joined
·
1,969 Posts
Discussion Starter · #2 · (Edited)
fuel filter continued

This was a job best performed in the driveway, to eliminate the buildup of gas vapors.

Jacked the car on driver’s rear side after setting wooden chocks under opposite wheel. Place stand under car – frame member is just inboard of the jack point.

The plastic cover for the fuel filter and pump assembly is on the driver side, just forward of the rear tire. It is held in place with three 10mm plastic nuts, two aft, one forward. Remove and you will see the filter and pump (blue middle in photo) suspended with rubber mounts from the car in a metal carriage. (A side note, my 1997 E420 has metal pan and the fuel carriage is directly mounted to the body. The filter is also a lot less expensive.)

NOTE: Before going further, I pulled the power to the fuel pump. The power connection has locking clamps that needed to be squeezed while pulling off the connection. I chose not to remove the battery power cable, to avoid all of the resets. I did not want the pump starting unexpectedly and run dry.

Loosened the metal carriage holding down the fuel pump and filter with a Phillips screwdriver. No need to remove the screw, just loosened to allow the filter to slide.

Placed the catch container beneath the pump and filter, and put on glove and glasses.

The factory installation of the filter has hose clamps that are one time use. I could not figure out how to get them off, and that is where the garden shears came into play. Three of the four connections included hose clamps, one for emissions return was only friction fit. Two things to consider. 1) Look at the length of hose between the pump suction and the filter so determine if you can shorten the hose and the remaining piece will still make the bend radius to the filter. If not, you will have to figure out how to remove the one time use clamp on the pump suction, and replace the line with new. This is the shortest of the hoses and most problematic. 2) Look at the new filter, and of the four connections, identify the one that states ‘TANK’. Then identify that connection on the installed filter.

NOTE: If anyone is replicating the next steps while smoking, please let me know so I can get you nominated for a Darwin Award.

Using the garden shears, cut the hose from the TANK as close the to the filter pipe nipple as possible. It will gush a bit from both the filter and especially the tank. Push the golf tee into the open hose going to the tank (see photo of hose plugged with tee). Otherwise, the entire gas tank will drain. Note the locations and cut the other two hoses, pull the filter out of the carriage and let it hang by the emissions connection to drain. (see photo, showing pulled pump power, tee plug, and loose set of new filter in carriage)
 

Attachments

·
Registered
Current 2017 GLE350, 2007 S550, 2002 S430, 1998 ML320 Deceased 74 240D, 92 400E, 97 E420, 13 GLK350
Joined
·
1,969 Posts
Discussion Starter · #3 · (Edited)
fuel filter continued

Ensured correct orientation of new filter and slid into carriage next to the fuel pump. Using appropriate size clamps, restored the hose connections to their correct locations. (The new filter was be labeled for which connection is TANK, PUMP, MOT, so it was hard to screw this up.) The new filter had plastic caps on the four pipe nipples that I did not remove until after it was set in place, and only just before placing a hose connection.

The old filter was directly centered in the carriage clamp. With the shortened bend radius of the filter to the pump suction, this was a different orientation (farther forward). I did not worry about the offset, and simply tightened the carriage clamp after the three hose clamps were installed and the filter found its ‘natural’ position from the spring of the hose lines.

After tightening all clamps, removed the emissions tube from the old filter and installed onto the new filter. The inspection mirror came in handy to check the back side of the clamped connections.

NOTE: Before going further, I restored the power connection to the fuel pump. (See photo of new installation)

At this point, after removing the gas soaked gloves, I leaned in and started the car. It took a few more cranks than usual (since the filter and pump had air in the system), but started within 5 seconds. While the car was running, I did a leak check on the newly installed filter. No leaks, so shut off the car.

Pulled the drain pan out of the way in order to reinstall the body panel that covered the pump and filter. The body panel has to be slid underneath the heat shield and then over the body studs. NOTE – The plastic 10mm nuts can be over torqued and miss-threaded easily. Take care, and don’t try to torque these things. They are designed to grip the body studs and won’t rattle off.

It has been a week, and no problems. Although I had not experienced any problems with car performance prior to the filter change, I did feel that it was worthwhile. When I made the cut from the tank to the filter some brown swill came out from the filter. Don’t know what it was, but the filter was obviously doing its job. Next filter change out will be easier because the installed hose clamps are now reusable.
 

Attachments

·
Registered
2000 S430 156k (11/12)
Joined
·
507 Posts
Nice write-up!
Did you have to soak the new filter before installing? This is next on my list.
Thanks.
 

·
Registered
Current 2017 GLE350, 2007 S550, 2002 S430, 1998 ML320 Deceased 74 240D, 92 400E, 97 E420, 13 GLK350
Joined
·
1,969 Posts
Discussion Starter · #5 ·
xexpo - hadn't thought of presoak. Is there an advantage?
 

·
Registered
2000 S430 156k (11/12)
Joined
·
507 Posts
I don't know, seen some people advising it, I am not sure what it does.
Your replacement went very well and things are working fine right? So, I am thinking there may not be an advantage.

Did Mr. Adams help at all, during the replacement?
 

·
Registered
Current 2017 GLE350, 2007 S550, 2002 S430, 1998 ML320 Deceased 74 240D, 92 400E, 97 E420, 13 GLK350
Joined
·
1,969 Posts
Discussion Starter · #7 ·
I did see one post where a mechanic indicated that fuel pumps occasionally become noisy after replacing the filter, requiring a new $400 pump.

Now that you bring it up, the presoak may minimize the air in the fuel filter and avoid air binding of the fuel pump. I did this job with a full gas tank, and it was about 15 minutes between putting the TANK hose line on, and doing the leak check test run. Maybe that was enough net postive suction head and time to avoid air binding the fuel pump.

Also, it was a warm day, and the job required help from two Mr. Adams! :thumbsup:
 

·
Registered
96 and 08 911 turbos
Joined
·
2,988 Posts
those clamps can be removed with a small flat head screw driver. You simply pry open the little loop until you can remove the band from a little hook. Makes sense if you look at it closely.

I wouldn't worry about the fuel pump or pre-soaking the filter.
 

·
Registered
2000 S430 156k (11/12)
Joined
·
507 Posts

·
Registered
96 and 08 911 turbos
Joined
·
2,988 Posts
some people pre-soak because they think that the sudden pressure of the fuel pump hitting the dry filter will tear it.

Not really a concern in my book.
 

·
Registered
2000 S430 156k (11/12)
Joined
·
507 Posts
It may be beneficial to soak the filter then. I am getting ready to replace mine and I may try it.
 

·
Registered
96 and 08 911 turbos
Joined
·
2,988 Posts
I would not bother. Never done this with the at least 30 fuel filters I've replaced over the last 12 years. Never an issue.
 

·
Registered
Current 2017 GLE350, 2007 S550, 2002 S430, 1998 ML320 Deceased 74 240D, 92 400E, 97 E420, 13 GLK350
Joined
·
1,969 Posts
Discussion Starter · #14 ·
On the circ clips, I did not know they were reusable. I tried multiple times to remove a few using a flat head screwdriver, without any success of getting the blade into the right spot.

I was out of town this past week and my wife's Lexus had the check engine light come on (RX330 73,000 miles). She took it to the dealership, who wanted to replace the fuel filter, amongst nearly all the emmisions control system. She wisely declined because there was, as of yet, no engine performance problems. My task over the coming weeks is to replace the filter, reset the check engine via ODBII, wait for the reappearance of the code, change the next part, and so on.

I will be curious to see how much swill come out of the Lexus fuel filter. (these use regular gasoline). For comparison, the photo below shows what I got out of the MB filter.
 

Attachments

·
Registered
Current 2017 GLE350, 2007 S550, 2002 S430, 1998 ML320 Deceased 74 240D, 92 400E, 97 E420, 13 GLK350
Joined
·
1,969 Posts
Discussion Starter · #15 ·
I would not bother. Never done this with the at least 30 fuel filters I've replaced over the last 12 years. Never an issue.
OliverK - How many cars do you have - or do you own a shop? What's the best spot to pry off the circ clip?
 

·
Registered
96 and 08 911 turbos
Joined
·
2,988 Posts
In that time I've had 7 cars. 2 audis, 1 blown mustang, an M3, E39 M5, E430, and the 220. The mustang required regular filter changes.

Don't own a shop but do all my own work.

Prying the clamp requires a very small flat head to get it started. At that point, you can pry it open a little at a time.
 

·
Registered
94 E320 Sportline sedan 86 190E 2.3 16V sedan 04 S430 Sport
Joined
·
678 Posts
how to replace a fuel filter on a 06 s500
The procedures listed will be the same for an S500.

Also, I see that you are fairly new around here, welcome to the forum. If you have not done so yet, I would recommend that you review the W220 encyclopedia posted in the sticky section of this forum. The encyclopedia has a TON of great information regarding our beloved W220's and lots of DIY information posted there as well.

The stickies are the first five posts in this forum just FYI, and will always be the first five posts..... enjoy and again welcome to the forum.
 

·
Registered
2012 S550 Bi-Turbo 4Matic
Joined
·
303 Posts
I am here to provide the other side of replacing the fuel filter by letting the dealer change it.
I am not so DIY inclined and decided to go with the dealer AFTER i read this thread last night and saw that cutting fuel lines and hoses from the tank is involved in this job.
I must say do not feel comfortable cutting the hose from the tank to the fuel filter and replacing the clamp, and having to check every time i get out the car there is no fuel leaking on the ground.
I decided to let the professionals do it for $152.

I know , I know, this forum is here mainly to help avoid the high cost at the stealership, but in some situations my peace of mind is worth the few extra bucks, and that is one of those times.
 
  • Like
Reactions: cerritos
1 - 20 of 30 Posts
Top