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Fuel Filter Question

marlen.padberg

New member
Having a coffee with a friend and I was outlining all the service work completed during this off-season, he posed a question about the Fuel Filter. I did a thread search looking for Fuel Filter, but couldn't find any mentions. Is there a fuel filter as part of the fuel pick-up/pump? Is there an in-line filter? What happens if I end up in a part of the world where the fuel quality is lower and the fuel has sediment in it? I imagine if there's no filter, dirty fuel would cause awful fuel system problems, clogged injectors, etc. Is the fuel filter replacable? Any part number references?

Any insight would be appreciated. Thanks!
 
Having a coffee with a friend and I was outlining all the service work completed during this off-season, he posed a question about the Fuel Filter. I did a thread search looking for Fuel Filter, but couldn't find any mentions. Is there a fuel filter as part of the fuel pick-up/pump? Is there an in-line filter? What happens if I end up in a part of the world where the fuel quality is lower and the fuel has sediment in it? I imagine if there's no filter, dirty fuel would cause awful fuel system problems, clogged injectors, etc. Is the fuel filter replacable? Any part number references?

Any insight would be appreciated. Thanks!

Model? Year?
 
Mine is a 2010 RT. I presume all 10-14 RT and GS would be similar. Hex heads the same?

Sometime about the time of the demise of the Oilheads I lost track of the associations of models and their head style, albeit cam head, hex head, wet head, or dead head. And back in my day even among the Oilheads and the Airheads and the K bikes there were significant differences. An R1100RS and R1200C were both Oilheads but hugely different beasts. An R60/5 and R100RT were both Airheads but not the same at all in their details. And even a K1200 could be two totally different models, one with a horizontal flat four and one with a vertical slant four engine, identified only by year. This slightly snarky post is to say that broad categories like camhead or hexhead don't help with details.
 
2005-2009: Hexheads
2010-2013: Camheads (very, very similar to the Hexheads)
2014-2018: Wetheads (Clean-sheet redesign)
 
Having a coffee with a friend and I was outlining all the service work completed during this off-season, he posed a question about the Fuel Filter. I did a thread search looking for Fuel Filter, but couldn't find any mentions. Is there a fuel filter as part of the fuel pick-up/pump? Is there an in-line filter? What happens if I end up in a part of the world where the fuel quality is lower and the fuel has sediment in it? I imagine if there's no filter, dirty fuel would cause awful fuel system problems, clogged injectors, etc. Is the fuel filter replacable? Any part number references?

Any insight would be appreciated. Thanks!

I think it uses a sock in the fuel tank. Try searching on max bmw site.
 
There are two lines of defense that I understand. There's a small screen "bag" on the bottom of the filter assembly. Plus there's a filter built into the pump assembly. BMW doesn't have any recommendations as to when to change either. It's not an easy thing to disassemble, but Mr. BestRest has a video. He also sells the screen bag.

If I were going to go someplace with suspect gas, I'd probably install a filter at the nozzle, a la the BestRest products.
 
Fuel Filter

Well thats an interesting approach. Would definitely give thought to that if going somewhere where you know the fuel quality is going to be questionable. Hadn't heard of guglatech before, but am suitably impressed by that video.

Regarding my existing pump/filter assembly, is the filter replaceable, and has anyone replaced their filter? Is this something I should give thought to at 120,000kms, or keep going and only change it if its causing grief?
 
There is only a sock at pump inlet on all models other than the metal tanked Roadster and the early Hexhead ST. I haven't seen any other filter even on the pump on the few I have sitting around from failed units
Those do have an inline filter. Not a clue why they dropped the filter and not a lot of places to really mount one on other models...though one certainly could somewhere.
The Roadsters is in the tunnel under tank, never looked at location on a ST

Guess they figured gas never gets contaminants:dunno

I don't worry about it and have two models with over 120K miles. Have had the add HEET once on mine when I had sputtering after fueling at a questionable but only game in town station. Have drained a lot of water from bikes sitting with half tank for some time...not mine, but two ruined the pump as well do to rusting on a GS and a K12S.
 
There is only a sock at pump inlet on all models other than the metal tanked Roadster and the early Hexhead ST. I haven't seen any other filter even on the pump on the few I have sitting around from failed units
Those do have an inline filter. Not a clue why they dropped the filter and not a lot of places to really mount one on other models...though one certainly could somewhere.
The Roadsters is in the tunnel under tank, never looked at location on a ST

Guess they figured gas never gets contaminants:dunno

I don't worry about it and have two models with over 120K miles. Have had the add HEET once on mine when I had sputtering after fueling at a questionable but only game in town station. Have drained a lot of water from bikes sitting with half tank for some time...not mine, but two ruined the pump as well do to rusting on a GS and a K12S.

Most cars no longer have a fuel filter, just a screen on the fuel pump. Diesel vehicles still use a fuel filter.
Maybe the filters on gas station pumps are better than they used to.
 
Regarding my existing pump/filter assembly, is the filter replaceable, and has anyone replaced their filter? Is this something I should give thought to at 120,000kms, or keep going and only change it if its causing grief?

The sock? Sure! You could always pull the pump assembly and see... if it's dirty, then you could get further into the fuel system. (Mr. Injector did a nice job cleaning my fuel injectors on my K75 a while back).
 
Most cars no longer have a fuel filter, just a screen on the fuel pump. Diesel vehicles still use a fuel filter.
Maybe the filters on gas station pumps are better than they used to.

And fuel pumps may be better or more tolerant than they used to be. And the gradual demise of the corrosion-prone metal underground fuel storage tank at gas stations may have contributed. Also in the mix could be the switch from Bernoulli-based carburetors and their obstruction-prone jets and passages, to pressurized FI systems.

Diesels will always have filters, mainly because of water-in-fuel issues that can not only leave one stopped by the side of the road, but can be destructive as well. Google “Bosch CP-4 fuel pump” on any of the light-truck sites for that story.

Best,
DeVern
 
Well thats an interesting approach. Would definitely give thought to that if going somewhere where you know the fuel quality is going to be questionable. Hadn't heard of guglatech before, but am suitably impressed by that video.

Regarding my existing pump/filter assembly, is the filter replaceable, and has anyone replaced their filter? Is this something I should give thought to at 120,000kms, or keep going and only change it if its causing grief?

Don't worry about it. It's not a scheduled maintenance item and you would probably need an inch or two of mud in your tank before it could clog.
 
Just my 2 cents on the guglatech filter - in my case in a GSA tank. Basically a Tyvek looking sock fitted under the filler neck. Installation was a bit more fiddly than the instructions showed but not bad. I have ~1.5 years of use and it does give me additional confidence when away from the beaten track, especially Mexico. That said, I have not pulled it to see what has been caught. Only downside is that it does call for more gradual fill ups at the pump despite what the PR states.
 
Hexheads and Camhead 1200's

There is a larger (than oilhead) filter built into the upper pump assembly that is not replaceable.
If it eventually clogs (loss of power at higher rpm) you have 2 options:
Replace the whole assembly $$$
or
Drill out wall in the filter and flush out backwards. Then install an external filter - the oilhead filter is a good candidate.

There is a how to video.
https://www.youtube.com/watch?v=xdyHT3pGm_A&ab_channel=BestRestProducts
 
The design changed on the liquid cooled bikes to provide for a replaceable filter although BMW only sells the entire assembly.

Pump Assembly.jpg
 
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