fuel filter change - PeachParts Mercedes-Benz Forum

blk90s13 · #1 10-17-2009, 02:13 PM

I already changed the little plastic filter and I have the can spin on filter to do next

Is there anything I should know before taking one out and putting a new one on ? was wondering if its pressurized and if I should follow any certain steps ?

Could not find much info covering this issue in search

thanks all

Junkman · #2 10-17-2009, 02:53 PM

No special tasks other than to make sure you fill the new filter with fuel before installing. Otherwise, you may be cracking the lines to bleed the air. I didn't change mine before going on a trip & found that both could be changed on the roadside without tools. Just unscrew it - normal right hand threads. I usually do both at the same time. Install 1 filter, start engine to purge all the air, install the other.

toomany MBZ · #3 10-17-2009, 02:54 PM

Quote:

Originally Posted by Junkman

No special tasks other than to make sure you fill the new filter with fuel before installing.

X 2.

simonshearer · #4 10-17-2009, 02:58 PM

Quote:

Originally Posted by toomany MBZ

X 2.

Is it normal to have to replace the metal seal at the top? Mine leaks now since the filter change this afternoon. I've ordered a new metal seal.

AlanTbird · #5 10-17-2009, 03:01 PM

I just did mine this am and filled the new one with some 2 stroke oil (SOME USE TRANNY FLUID) I use it in the tank about every 3rd fill up to lubricate things and it took about 4 tries to start but did and fogged the hood!

Diesel911 · #6 10-17-2009, 03:06 PM

You need to have on hand any O-rings or Seals if your model uses a Filter Bolt. While they often can be reused you never know if the Old ones will leak until you run your Car.

Diesel911 · #7 10-17-2009, 03:16 PM

Quote:

Originally Posted by simonshearer

Is it normal to have to replace the metal seal at the top? Mine leaks now since the filter change this afternoon. I've ordered a new metal seal.

The old style Filter Bolt comes with an Aluminum Crush Washer and 1 O-ring at the bottom. I think it is a good idea to have both before you change your Spin-on filter.
If you can find them Copper Crush Washers last longer and seal better and 1 member said he cured a leaking one that no normal Crush Washer would stop with the one in the pic below from I think it was ACE Hardware.
NU-lip bonded aluminum washer.

toomany MBZ · #8 10-17-2009, 03:55 PM

Quote:

Originally Posted by simonshearer

Is it normal to have to replace the metal seal at the top? Mine leaks now since the filter change this afternoon. I've ordered a new metal seal.

Yes, not all filters have that. I ended up using a composite washer I got from the hardware store. A "#30 CAP THREAD GASKET".
Some supply houses provide that washer with the filter , some don't.

sasquatchgeoff · #9 10-17-2009, 04:45 PM

Don't over-torque the bolt.

Thall Shalt Not Over-Torque Thine Fuel Filter

Skid Row Joe · #10 10-17-2009, 05:46 PM

Quote:

Originally Posted by blk90s13

I already changed the little plastic filter and I have the can spin on filter to do next

Is there anything I should know before taking one out and putting a new one on ? was wondering if its pressurized and if I should follow any certain steps ?

Could not find much info covering this issue in search

thanks all

Well, with an older model MB diesel - I'll give you my version of how I change my main 'spin-on' fuel filter; first of all, the main filter in my experience is not meant to be 'spun-on.' What I do is grasp the lower part of this filter tightly in one hand, and without stripping the large banjo bolt head - unscrew from the filter, but backing the bolt out of the filter assembly.

Next step is taking a new fresh main filter - and back-filling it with fresh diesel fuel, mixed with Power Service diesel fuel conditioner - filling the filter almost to it's brim, so's you don't have to do as much pumping of the white plastic unscrew pump through valve up-line in the fuel line from the fuel tank. Support the main filter with one hand in-place, whilst you re-thread the banjo bolt down into the filter. When almost snug, stop, and start pumping with the in-line white plastic fuel line pump, until fuel squirts out of the top of the almost snug banjo bolt. Grasping the main filter, pushing it up against the frame base, finish tightening the bajo bolt firmly into the main filter. Wipe off accumulated, fuel from filter and surrounding areas.

With a W210 model, such as I own, there is no in-line pump assembly, so the cranking of the engine fills the remainder of the main fule filter, completely filling the system with diesel fuel.

Cr from Texas · #11 10-17-2009, 06:24 PM

Quote:

Originally Posted by Skid Row Joe

Well, with an older model MB diesel - I'll give you my version of how I change my main 'spin-on' fuel filter; first of all, the main filter in my experience is not meant to be 'spun-on.' What I do is grasp the lower part of this filter tightly in one hand, and without stripping the large banjo bolt head - unscrew from the filter, but backing the bolt out of the filter assembly.

Next step is taking a new fresh main filter - and back-filling it with fresh diesel fuel, mixed with Power Service diesel fuel conditioner - filling the filter almost to it's brim, so's you don't have to do as much pumping of the white plastic unscrew pump through valve up-line in the fuel line from the fuel tank. Support the main filter with one hand in-place, whilst you re-thread the banjo bolt down into the filter. When almost snug, stop, and start pumping with the in-line white plastic fuel line pump, until fuel squirts out of the top of the almost snug banjo bolt. Grasping the main filter, pushing it up against the frame base, finish tightening the bajo bolt firmly into the main filter. Wipe off accumulated, fuel from filter and surrounding areas.

With a W210 model, such as I own, there is no in-line pump assembly, so the cranking of the engine fills the remainder of the main fule filter, completely filling the system with diesel fuel.

That's my procedure except I prefill with ATF (don't remember why but that's worked for 26 years and easier to pour out of a quart bottle than mess with #2). I've never used the primer pump.

Diesel911 · #12 10-17-2009, 11:36 PM

Since I am to fumbly to keep a Filter filled with Diesel Fuel under control without making a mess.

I lube up the rubber Filter Gasket (stick my Finger in a bottle of Engine Oil and rub it on the rubber gasket).

If I thought the O-rings on the Filter Bolt needed replacing I replace them. Lube the O-rings also.

I shove the blolt in and I do spin the Filter itself on. I think get a better feel as to how tight the Filter is that way (I do turn the Filter Bolt when I remove the Filter until it is loose).

After that I just pump on the Hand Primer until I hear a squishing, buzzing sound comming out of the Overflow Valve on the Fuel Injection Pump. After that I pump a little more to be sure.

Then I start the Engine and look for leaks.

If I remember after the Car has been driven some I will check for leaks again.

If I had an Engine with no hand primer or I would fill the Filter with Diesel Fuel and do the best I could to try not to spill any.

blk90s13 · #13 10-18-2009, 12:33 AM

Some times I wish all the automobile forums I am on is as helpfull and the Shopforums oh well

Do I have a manual pump ? where is it ? cant I just do it as I do on my cummins I change the filter and cycle the ignition key 2-4 times and that is usualy enough to fill the filter

I Will fill it with 2 cycle oil as I use it in the tank every fill up anyway

Thanks all

toomany MBZ · #14 10-18-2009, 08:21 AM

^ I think that engine does not have a manual primer, but not sure.

Jeremy5848 · #15 10-18-2009, 11:45 AM

Quote:

Originally Posted by blk90s13

. . . Do I have a manual pump ? where is it ? cant I just do it as I do on my cummins I change the filter and cycle the ignition key 2-4 times and that is usualy enough to fill the filter . . .

Your car has an OM602 engine, AFAIK it does not have a primer pump. I think it was Brian who suggested filling the new secondary filter only 3/4 full of fuel or whatever witch's brew you like. It's almost impossible to get a filter full of fuel into place without spilling. With the filter sitting in place and the top bolt removed, you can use a wooden wedge or other lever-like tool to push the filter up against the base.

Now use a small funnel to fill the filter the rest of the way and put the bolt in. Replace the o-rings if they look at all flat or worn, tighten the bolt not the filter, and don't over-tighten. With the filters full of fuel, the engine will start and run immediately. I find that keeping the engine speed up a little (1000-1500 RPM) helps to make sure the engine doesn't die on you until all of the remaining air bubbles are blown out.

Jeremy