Fuel Filter outside the fuel tank

[strsout]

On another board I belong too (GS related) there is a lot of talk on moving the fuel filter outside the fuel tank, for practical reasons.

I could not make up my mind so far, most for lack of knowledge on this matter, so I decided to bring it here :)

The ones who are pro it, they claim that it's much easier to change fuel filter on the road, when you got bad gas and it clogs the filter, etc. etc. and that if you use the right hoses and clamps, the 40psi will not blow the fittings and you will never have gas spill over your hot engine and burn your bike.

On the other hand, the ones who are con it, they claim that the risk to have a blow out and a big fire on your bike are very high due to the high pressure on the fuel line.

The pump produces about 40psi on the fuel line. What would be the implications on moving the filter outside the fuel tank? If you use a brand name metal filter and good clamps is there any real risk on it?

Then, why those Germans put it inside the fuel tank? Is that a 'normal' local for the filter?

Thank you for your inputs. :)

[rdwalker]

At first, when I got into the K-bikes with internal fuel filter, I also entertained the idea of moving it out. Then, though, I decided that it is better left alone.

Internal filter is used mainly for the sake of space-efficiency and to avoid problematic leaks. It is routine on fuel-injected cars and that is probably why it was a logical move to the bikes.

As for my decision to leave well enough alone, I do not expect to have to look at the filter on the road. Normal service intervals are so long that we always have the luxury to work on it in the comfort of our garages. If that need for service happens on the road, I'll probably have so many other issues to attend that pulling the tank will be a minor one.

However, most importantly in my position against the move, is the risk of leaks. I already experienced some small seeps and one major blowout from the injection hose connections.

Yes, the blowout was caused by me using worm-drive clamps (which loosened) instead of the crimp ones, but there is alway a possibility of some screw-up, no matter how careful you are. And let me tell you, sitting on a bike while your leg is being power-washed with high-test gasoline is an interesting experience.

My 2 cents.

[BMB02]

How to Change a Fuel Filter

1. Locate and replace the fuel filter
A vehicles fuel filter is used to keep the fuel that is used in the fuel injection system clean to avoid plugging fuel injectors and fuel pressure regulator. The fuel filter should be changed between 25,000 and 35,000 miles depending on driving conditions. First locate and identify the fuel filter, all vehicles are different so you might have to look around for it. Some are under the hood and others are under the car or truck like the one used in this example.
2. Remove the fuel filter connection . Remove fuel filter connections from fuel lines. A small amount of fuel will leak out when connections are removed. Next remove the fuel filter mounting bracket bolt and remove filter.
3. Install fuel filter mount. Remove fuel filter mount from old fuel filter and install it on the new fuel filter. Make sure that the direction arrow is pointing in the direction of the engine. (forward in most cases)
4. Install new fuel filter. After the fuel filter mount is installed reinstall fuel filter. Make sure the sealing "O" rings are in place, in good condition and free from debris. Remount filter and reconnect. Start vehicle to check for leaks
I've searched this on the net 'coz I'm having some difficulty with my BMW fuel filter (http://www.advancebmwparts.com/bmw-fuel-filter.html) installation... ;)

[jayjacobson]

....there is a lot of talk on moving the fuel filter outside the fuel tank, for practical reasons....

The ones who are pro it, they claim that it's much easier to change fuel filter on the road, when you got bad gas and it clogs the filter, etc. etc. and that if you use the right hoses and clamps, the 40psi will not blow the fittings and you will never have gas spill over your hot engine and burn your bike.

On the other hand, the ones who are con it, they claim that the risk to have a blow out and a big fire on your bike are very high due to the high pressure on the fuel line....

Then, why those Germans put it inside the fuel tank? Is that a 'normal' local for the filter?....
A fuel pump/pre-pump and/or fuel filter inside the tank is very common on the kraut mobiles. In addition to a course filter inside the tank, there is usually a fine filter outside the tank. Often, the main fuel pump is outside the tank, also.

If you use good quality fuel injection hose and good quality clamps, you will not have any problems. Worm clamps are fine. Do not over tighten clamps! If it makes you feel better, Lock-Tite the worm clamps with a few drops of Red. You will have to cut the clamps off, however. 40 PSI is not high pressure as far a fuel injection goes. So hoses splitting apart and clamps blowing off are not a factor as long as you use quality materials.

I replace my fuel filter at a maximum mileage of 15k. Helps to keep the fuel system clean and the injectors from clogging. I've never had a problem with bad gas clogging my fuel filters--even using ARCO (which I do not do on a regular basis). "Cheap" gas lacks the additives of the better quality gas, so you may get more deposits. A jar of Techron and Marvel Mystery Oil every 3k will tighten that up.

So, bottom line: no prob if you want to move the fuel filter outside the tank. Just watch your placement so that filter and lines are as far away from heat sources as possible. Leave enough slack in the hose for some movement. Good luck and enjoy your ride!

[CharlieVT]

Everytime this subject comes up I just wonder. Seems to me a solution in search of a problem. If you just want to tinker and fix something that isn't broken, go ahead. My bet is that if you add up all the time you will spend changing the fuel filter in its normal location over the life of the bike the total time spent will be less than the time you spend reengineering an external location. Doing this to save time and make it more "convenient" makes no sense.

If one wants a bike that is more "fixable" by the side of the road why ride a computer controlled, fuel injected bike in the first place? You want a roadside fixable bike get an old airhead, that's where BMW earned its reputation of durable simplicity.

There are a host of problems that can occur that you just aren't going to fix by the side of the road. Murphy's law has it that if you modifiy the bike so you can change the fuel filter easily in the case of "bad gas" you'll never find any bad gas, but something else will go wrong. And if you are LD riding with the luggage constraints that packing for LD requires, do you really want to add an extra fuel filter to your gear just in case?

My take on the folks that decide to move their air and gas filters to a "better" location are just looking for a project. That's fine, projects are good fun, enjoy the project. But you aren't going to convince me it is a genuine improvement.



On another board I belong too (GS related) there is a lot of talk on moving the fuel filter outside the fuel tank, for practical reasons.

I could not make up my mind so far, most for lack of knowledge on this matter, so I decided to bring it here :)

The ones who are pro it, they claim that it's much easier to change fuel filter on the road, when you got bad gas and it clogs the filter, etc. etc. and that if you use the right hoses and clamps, the 40psi will not blow the fittings and you will never have gas spill over your hot engine and burn your bike.

On the other hand, the ones who are con it, they claim that the risk to have a blow out and a big fire on your bike are very high due to the high pressure on the fuel line.

The pump produces about 40psi on the fuel line. What would be the implications on moving the filter outside the fuel tank? If you use a brand name metal filter and good clamps is there any real risk on it?

Then, why those Germans put it inside the fuel tank? Is that a 'normal' local for the filter?

Thank you for your inputs. :)