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Fuel Filter install DIY, observations and tips

111K views 113 replies 70 participants last post by  catfood12  
#1 · (Edited)
So in my quest to replace anything on my M5 that is getting "old" I have arrived to the fuel filter. The BMW TIS makes this install look very, very simple. the install is pretty straight forward but not as cut and dry as the TIS makes it out to be.

Tools:
Plastic rivet tool (or a screwdriver if your feeling lucky)
1/4'' rachet with 10mm and 8mm short sockets
1/4'' extension
Flat head screw driver (small)
Large 17mm open end wrench
Large 7/8'' open end wrench
New Filter ~$100 from dealer
Large pan to catch old fuel
Liquid refreshment (of course!)
I suggest a few pairs of rubber gloves, you will get fuel on you.

First off the pan is located under the drivers door on our M5's. This pan is secured by almost 10 screws. Now in true German fashion these are a combination of 10mm nuts, 8mm nuts and plastic pop rivets. Oh what a joy it is to take all these out! (don't forget the two 10mm's in the wheel well). Then you realize that the cover is tucked underneath the rubber jacking point, Doh! So now you need to get the car off the jack stands to get the cover out from under the jack point. Now that the covers off and you get hit with 60k miles of road debris and grime that was hiding under the cover :grrrrr: you get a look at this monster of a fuel filter.

Sorry I did not take any pics, but I had fuel all over my hands and we all know what plastic+fuel equals. My first MAJOR note is that the TIS gives you no information on how to depressurize the system. Just a generic warning that the system can hold up to 5bar of pressure (careful that will put an eye out). Fortunately our friends at BMW are on our side once again. there is a small valve (identical to a tire fill valve) with a metal cover on it (identical to the factory metal tire valve stem covers). I assume this port is designed for diagnostic purposes but it works fantastically to depressurize the system. Use a small screw driver, put a large pan under the car and look the other way when depressing this valve. Also use common sense, do this in an open garage and with no source of ignition near you. I take no responsibility for you nuking your house/family/pets. This takes approx 30 seconds and a good bit (1/2 a cup) of fuel will come out.

With the system depressurized the "quick connects" on the fuel lines are very easy to use (Thanks you again BMW, my Audi fuel lines were designed to self destruct when played with, I learned that the hard way, nearly $1000 later). Simply push the plastic retaining collar into the coupling and pull on the line. Remove the in, the out, and the return line to the gas tank. then simply pull the small vacuum hose off the regulator. With everything disconnected remove the 2 10mm bolts holding the unit in place. Careful there is a good quantity of fuel in the filter.

Now on to removing the regulator. The TIS gives you no instructions for this and my regulator was frozen on the filter pretty good. I used a 17mm and 7/8'' open end wrench. This allowed me to rotate the unit separately and remove them with no problem. Also make sure you transfer the small plastic washer from the old filter to the new (my new filter did not come with one). Put the regulator on the new filter and tighten to a good snug hand tight. Reinstall the metal clamps on the new filter. Put the filter back into place is just a reverse operation. Fuel lines should audibly "snap" into place. Make sure and give each one a good tug to ensure it is engaged.

Observations:
This is obviously not a HP mod, just simply preventative maintenance. The #1 cause of fuel pump failure is a clogged fuel filter. This small investment (~$100 from my dealer) could keep your pump happy for many more miles.

With the old filter drained it still had a significant weight advantage over the new one, indicating that it was pretty full of crap. Plus when you turn it upside down, nasty black fuel comes out.

Easy job, can prevent power loss and later problems.

Keep the rubber side down,
Ryan
 
#2 ·
Very nice writeup. First spark plugs, now this. Keep them coming! Thanks.
 
#4 ·
Thanks good write-up. Always wondered where the filter was hidden. Please tell me more about the $1000 Audi fuel filter thing. I hope it didn't catch fire!
 
#5 ·
ELEVENS said:
Thanks good write-up. Always wondered where the filter was hidden. Please tell me more about the $1000 Audi fuel filter thing. I hope it didn't catch fire!
Audi's lines are ALL one piece, line connector and all. BMW has hard lines that break into soft lines shortly before the connector. If you break a connector on a BMW I would assume you just replace the short section at the end. In the case of my Audi I broke a connector on the engine side, required replacement of the entire line from filter to engine. Dealer charged me near $1000 for parts and labor..then kindly stated to me that they do not even replace fuel filters unless there is a severe problem due to the brittle connectors.
 
#6 ·
Yikes, the Audi setup seems scary to attempt to replace by oneself...

I too replaced my fuel filter not too long ago, without any immediate need (e.g. no SES light), but I tend to do things pre-emtively. I was surprised to hear that Circle BMW from whom I bought it (and is a big seller on this board) had no prior history of sales for these on the E39 M5s. So must be a rare occurence that they do need replacement...
 
#7 ·
cosioboy said:
Yikes, the Audi setup seems scary to attempt to replace by oneself...

I too replaced my fuel filter not too long ago, without any immediate need (e.g. no SES light), but I tend to do things pre-emtively. I was surprised to hear that Circle BMW from whom I bought it (and is a big seller on this board) had no prior history of sales for these on the E39 M5s. So must be a rare occurence that they do need replacement...
In my experience fuel filter rarely go bad themselves. They normally take out your fuel pump, then your find out that the pump has been working double time to push though a dirty filter. In my opinion it is something everyone should do pre-emtively.

-Ryan
 
#8 ·
The reason many dealers don't report large fuel filter sales is because when BMW began offering its extended maintenance plan the fuel filter along with other once wear-and-tear items became "lifetime" items. The published expected lifetime before extended maintaince? 30,000 miles.

Replace the fuel filter and watch the dirty fuel spill out of the inlet side. I don't care if it's lifetime or no, that just can't be healthy for the fuel pump or engine.
 
#9 ·
Nabio said:
The reason many dealers don't report large fuel filter sales is because when BMW began offering its extended maintenance plan the fuel filter along with other once wear-and-tear items became "lifetime" items. The published expected lifetime before extended maintaince? 30,000 miles.

Replace the fuel filter and watch the dirty fuel spill out of the inlet side. I don't care if it's lifetime or no, that just can't be healthy for the fuel pump or engine.
Funny you should mention that. This was my conversation with the parts guys when buying rear diff plug seals and the fuel filter:

Me: Can you set me up with two rear end seals for the drain and fill plugs, my TIS tells me I need to replace them.

Parts dude: You know that there is lifetime fluid in there and it never has to be changed.

Me: I don't believe in lifetime fluids.

Parts dude: Well, I have never heard of them changing the fluid in the rears before.

Me: Ok, i'll bring you a copy of the UOA from the rear, I am sure it will have all sorts of metals and clutch material in it.

Parts guy: Ok heres the seals, anything else?

Me: I need a fuel filter as well.

Parts guy: You know thoes do not need to be changed either.

Me: *evil eye*

Parts guy: Ok, i'll go get it.

-Ryan
 
#13 ·
Just the did the fuel filter swap. I would like to add my 2 cents.

I did not remove the platic pop rivets, but all the other screws and bolts mentioned. I attached a piece of string between the car jack and a hole in the plastic dust shield, to hold the shield out of the way.

I use three carpenter clamps (/w soft rubber ends) on the three rubber fuel lines to prevent fuel spillage, prior to removing the lines.

Also look at the new filter threaded end, to give you a hint on how to remove the fuel regulator off the filter.
 
#14 · (Edited)
HI guys,
Two questions for ya

1. I read in a previous thread that this is potentially risky as a DIY project due to the fear of trapping air bubbles in the fuel line (which could potentially cause engine damage). Did any of you guys encounter this/worry about this? Is there an easy way to purge air out during installation?

2. How many miles do ya all have? My beast is at 37k, I love working on it...should I bother to do this yet?


Thanks,
Brian
 
#15 · (Edited)
Blockdoc said:
HI guys,
Two questions for ya

1. I read in a previous thread that this is potentially risky as a DIY project due to the fear of trapping air bubbles in the fuel line (which could potentially cause engine damage). Did any of you guys encounter this/worry about this? Is there an easy way to purge air out during installation?

2. How many miles do ya all have? My beast is at 37k, I love working on it...should I bother to do this yet?
Hi Brian. I just got my 2002 beast with 69,000 Miles less than one month ago. I did my fuel filter swap at 70,000 Miles, spark plugs, air filters, oil swap, tranny oil swap, diff oil swap, and combustion chamber/throttle body spray cleaning, as part of the preventive maintenance when I acquire a "new" car.

I think this is an OEM "Inspection 2" 60K Miles maintenance item.
 
#16 ·
Nice write up Ryan...I took some pics.

A tip to relieve the fuel pressure so you don't get it all over your hands/gloves. Pull the fuel pump fuse (think #31) in the glove box. Start the car and it will die after a second or so. Start it again...it will just turn over. This will relieve the majority of the pressure. When I unscrewed the tire valve looking device by the fuel filter only a couple of drops of fuel came out.






Jeff
 
#17 ·
That´s a good way to depressurize, I think. (pulling the fuel pump fuse from the trunk mounted fuse panel is how I do the depressureizing before cylinder compression testing)

Keep starting the engine until it no longer starts. Then turn it over a few more times.

There is one important thing: have a powder type fire extinguisher on hand.

There is a non-return valve in the fuel pressure regulator, such that the fuel can only move into the return line (going from the regulator back to the fuel tank).

If the return line gets clogged, there will be lots of pressurized fuel in it even after depressurizing the rest of the system.

(Same thing if the car won´t start at all: a fully cloged fuel filter would trap pressurized fuel even after depressurizing.)

David
 
#19 ·
How do you get the quick connects to disconnect? The plastic pieces don't push far into the connectors (at least using finger force - not pliers), and I don't really want to yank on the fuel line to get it loose if the connector hasn't really released. Or maybe the plastic piece has to be rotated to align into the metal connector?

Would someone please provide a bit more detail on what this should feel like? Don't want to "hose" this up. Otherwise, this is a pretty simple job.

Thanks.
 
#20 ·
I had reservations as well. No need to align anything. Pull the plastic piece toward the hose with your fingers (may want to wear a glove to get a grip). Just keep playing with it and you'll see how it works.

Jeff
 
#23 ·
Had a problem, clicking off as well. I took an old 8mm or 10mm crescent and ground it down so it was thinner and used it to push the clip in.

By the way the pressure release valve only gets rid of the pressure on the engine side. If you have a very clogged filter (90k miles on it) then there is significant pressure on the tank side even after using the pressure release valve a couple of times.
 
#25 · (Edited)
Remove your gas cap in the furture. This should release any pressue on the tank side.

-Ryan
 
#24 ·
Zen and the art of motorcycle maintenance

RDM190/Ryan, Nice write up thanks! Saw the M5 Fuel filter on line at Tischer BMW for $47.80.

Besides the TIS (just ordered mine, haven't received it yet), is there a repair manual printed for our cars? The E39 Bentley Manual doesn't seem to cover the M5 cars I notice....

I'm a proactive maintenance guy too. When buying a car used, I can't always know for sure whats been done, even by checking the dealer maintenance records. Makes me uncomfortable. So to restore piece of mind and know that I've done the best I can for the automobile, I ignore the permanent fill/filter BS and just follow the same schedule for every car, keeps it simple and easy for me to keep track:

2X year oil changes (for me, Spring and Fall) and a bottle of Techron
Air Filters/Micro filter Once a year
Everything else, every other year, to include, plugs, fuel filter, and every other fluid in the car, even the power steering fluid if I have to change a belt for example. O2 sensors when they fail.

Makes me feel good. So I do it. Then I have no guilt when I pound on the car! :noSMG: It also gets me a higher resale value for my cars when the time comes. I also provide a recommended maintenance list and tell new owners to ignore what the dealers say, continue to maintain the car the same way and it will last a very long time!

Thanks again for the write up!
 
#26 ·
My car is 2002 with 110000 km (70000 mls) on it. I had the fuel filter replaced yesterday. After the change the car revved more freely. The difference was amazing.

It seems that if the filter is restricting the fuel flow when it is most needed. Based on this experience I would recommend changing the fuel filter every 50000-100000 km (35000-60000 mls).