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Just getting some first hand experience from others with KTM fuel filters and fuel pumps. 

We’ve had a 16’ 500 fuel pump go bad at least twice. Once when it was almost new. Now we think a 17’ with 80+ hours may have a plugged in the tank filter. 

Apparently they use a Mahle KL97 filter which appears pretty easy to order for under $10. 

Pictures below are a black used one in need of replacement and a what a new one looks like. 

So what are your experiences with replacement of the filters and or pumps lasting in hours or years. 

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Ive heard the filter internals turn black almost instantly, Ive never changed mine yet, hundreds of hours, there are automobiles with smaller filters than go thousands of miles. So why would these fail at shorter distances, barring any contributing contamination.

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6 minutes ago, Spud786 said:

Ive heard the filter internals turn black almost instantly, Ive never changed mine yet, hundreds of hours, there are automobiles with smaller filters than go thousands of miles. So why would these fail at shorter distances, barring any contributing contamination.

Good point. Maybe it’s the fuel pump and not the filter. The rider on the 16’ changed the whole pump. 

Unless others are changing the filters I will likely just run it until it loses power or maybe change it every couple hundred hours? 

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Rumor has it that the filters turn black due to the fuel pump motor brushes.
I find this odd that brushes wear at a rate to cause quick filter discoloration, but it is what it is. I wonder how many other fuel pump systems share this design.

Roost!

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Just from what I read, the small pumps have to work harder than automotive size or big bike pumps which equals more wear. Spud runs his bike more than most, so I check out his threads for FI history. A boat mechanic told me, never run the pump dry, change your filter and test the pump for pressure  periodically. Add a tank filter that not much else I see for prevention.

Quote

the motor can and its brushes are not exposed to the fuel or you would go BOOM !

Actually it is AB. Check this out and see what you think. About 4:00 minutes for the small pump. I guess they never get to the 4-14% flammable range of gasoline being in the tank.

Walking through the Home depot, Makita is starting to build brushless electric tools, smaller, stronger, and lighter. When do we see that on the tank pumps?

 

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Iv changed mine and opened the old filter and yes, the black stuff is a black shiny residue from the pump brushes. 

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AirBoss,  Those pumps DO have their brushes exposed to the fuel (for cooling too) - in the lack of air, it would not be a hazard, but get too low on fuel and hopefully there isn't enough oxygen in that area to support combustion.

I like the idea of a brush-less motor too - powerful, probably more efficient, and less items to wear or get hot.

Fuel keeps all in-tank fuel pumps cooled, that's why you shouldn't let your car's tank go to E too often.

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Anyone else here know someone who had a pump quit? None of the guys I ride with - so far. They have changed the KL 97 and they don't run it low on fuel. (500's & 690's & 450 XCF).

 

Mine after 50 hrs. They all look bad the 1st time you change it.

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I put about 150 hours on my Mahle KL97 filter...black of course.  Decided to change it for no particular reason...it just bugged me that it was black and it hadn't been touched in 5 years.

Took it out , took it apart...no trace of any kind of residue that I could find.  Put in a new one and everything was exactly the same as before....except my Mahle filter looked prettier than it used to.  Seemed like a very minimal return on time and money.

They just go black..personally I wouldn't worry about it at all.

Now your fuel pumps failing on you...that's a different story and one you need to chase down i guess.  I've never had a problem with mine (2012 350 XCF-W)...my riding buddy with the same bike (one year newer) has never had a problem either. Personally I doubt that your Mahle KL97 has anything to do with the fuel pump problem.....at least the fact that its turned black has nothing to do with your problem.

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6 hours ago, Airboss/oc said:

the motor can and its brushes are not exposed to the fuel or you would go BOOM !

I thought that too, but evidently not.  The most common failure Ive seen is if you get a defective new filter with a crack in it from the factory. That causes the fuel pressure to drop , which causes running issues.

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On ‎3‎/‎28‎/‎2018 at 8:55 AM, Burnrider said:

Just from what I read, the small pumps have to work harder than automotive size or big bike pumps which equals more wear. Spud runs his bike more than most, so I check out his threads for FI history. A boat mechanic told me, never run the pump dry, change your filter and test the pump for pressure  periodically. Add a tank filter that not much else I see for prevention.

Actually it is AB. Check this out and see what you think. About 4:00 minutes for the small pump. I guess they never get to the 4-14% flammable range of gasoline being in the tank.

Walking through the Home depot, Makita is starting to build brushless electric tools, smaller, stronger, and lighter. When do we see that on the tank pumps?

 

good video thanks explains a lot. this is my second FI bike the first being a '06 Montessa Trials which also came FI but was not battery powered. the gray residue is just the brushes seating-in and should decrease over time. jeez I'm riding a timebomb

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I changed my fuel filter at 300 hours and 12000 miles on a 13 500EXC.Lots If black stuff came out of old filter but the bike was running fine.

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Just an FYI post. I changed my pump fuel filter on my first 500 at about 600 hours when it began starving for fuel, problem solved and sold that bike at 18,000 miles and 771 hours on original fuel pump. It also had the black crap being described by everyone else. One more bit of information, I went to O'reilly auto parts and used a filter off the parts shelf to see how it would fare. Plastic see thru filter about the same length and hose diameter cost $5.99. no issues. Functioned fine next 171 hours.

On second 500 now and have not changed the fuel pump filter yet at 13,000 miles and 546 hours, although I believe it is just about time to prevent the same scenario. I will shoot for 600 hours then swap it out.  I do run a fuel filler screen on the tank and change my inline filter about every 3 or 4 months. Cheap insurance at $6

 

 

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On 3/30/2018 at 5:15 AM, eric33 said:

Just an FYI post. I changed my pump fuel filter on my first 500 at about 600 hours when it began starving for fuel, problem solved and sold that bike at 18,000 miles and 771 hours on original fuel pump. It also had the black crap being described by everyone else. One more bit of information, I went to O'reilly auto parts and used a filter off the parts shelf to see how it would fare. Plastic see thru filter about the same length and hose diameter cost $5.99. no issues. Functioned fine next 171 hours.

On second 500 now and have not changed the fuel pump filter yet at 13,000 miles and 546 hours, although I believe it is just about time to prevent the same scenario. I will shoot for 600 hours then swap it out.  I do run a fuel filler screen on the tank and change my inline filter about every 3 or 4 months. Cheap insurance at $6

 

 

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Well, when you do let us know which $6 filter you used. I bought a bag of 10 of the Mahle filters pretty cheap several years ago but it would be nice to know which off the shelf would work in jam.

Edited by KAG

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Sorry, didn't think to add pic. just sharing info and I only get to this forum every few days.

I keep a couple now in my inventory and carry one on long trips. Just got home from a 1500 mile Baja ride.

KTM filter.jpg

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