Fuel filter

timbox2 · Post by **timbox2** » Sat Oct 06, 2007 6:31 pm

Having just got back from a ride around mid wales with Lars I decided to replace the fuel filter which I bought a few weeks back but never got round to fitting.

Blimey, surprised the bike ran, whenI got it off I compared how much resistance to blowing through, really had to puff to get any air out as opposed to the new one which feels as though there is no restriction at all, I realise the old ones still wet with fuel but even so.

Also there was all sorts of nasty in the tank which I sucked out with a large syringe, a browny liquid which was heavier then the petrol, Im assuming water.

guess what, fuel pump loads quieter than it was, job done.

Lars1974 · Post by **Lars1974** » Mon Oct 08, 2007 7:31 am

Hey Tim,

glad to hear that you got your fuel filter sorted..
maybe i should take a look at my one too...as i think i can hear my fuel pump working all the time...
was it difficult to do?
have fun,
Lars

scotty · Post by **scotty** » Mon Oct 08, 2007 12:50 pm

Tim

How many miles has your bike done ? I think mine might also need changing as it's done near 52K on the original.

oyster · Post by **oyster** » Mon Oct 08, 2007 5:57 pm

Scotty : I think mine might also need changing as it's done near 52K on the original.

The Book describes fuel filter change is required at 24000 miles, so please fit a new one now and send me the new one that should have gone in 24000 miles ago.

Where poor grade petrol is in use, this should be changed every 12000 miles.
The brown, oily looking stuff in the bottom of the tank is usually stained water. If present, it will probably have got into the filter, where it obstructs petrol flow and may have got past and sticks to the gauze on the top of the injector, obstructing petrol flow.
A good thing to do is to get rid of the water, via the balance pipe for the tank; a new filter for any in there; to remove the injectors and give them a squirt with carb cleaner and to leave the supply pipes disconnected to allow them to dry out completely. On reassembly, given that the fuel pipes are correctly reconnected, the bike will run with a renewed vigour.
I know all this from recent experience.

timbox2 · Post by **timbox2** » Mon Oct 08, 2007 6:31 pm

Lars1974 wrote:Hey Tim,

glad to hear that you got your fuel filter sorted..
maybe i should take a look at my one too...as i think i can hear my fuel pump working all the time...
was it difficult to do?
have fun,
Lars

Wouldnt say difficult, a bit tricky, oh and I would make sure you have a supply of new petrol pipe clips as they are all the crimped use once variety apart from where they join to the plastic pipes half way down the engine.
And dont forget a new access cover seal, I had to prompt the BMW parts guy to give me one, only a couple of quid more, you dont want that leaking down your leg

run the bike as near empty as poss but still get some form of clamps for the supply and return hoses before you disconnect them, or like me you get a petrol face wash, not nice, but still better than my usual cologne according to the missus.
Worse bit really is taking the fairing panels off, then manoevering the pump and filter assy out of the tank, take your time and its fine.

scotty wrote:
Tim

How many miles has your bike done ? I think mine might also need changing as it's done near 52K on the original.

Mines done 33k and although Ive got all the history cant find any mention of the fuel filter ever being changed.

scotty · Post by **scotty** » Tue Oct 09, 2007 9:12 am

Thanks Oyster

Time for a fuel filter change then. I might as well do this now as I currently have the panels off to clean the air filter. Besides the fuel filter itself what other bits should I order first ? I have never had the tank off yet so this is a first for me. I know some of the fuel pipes are pressurized and will need clamped off. It's surely worth fitting fuel line couplers to fit on all the pipes thereby allowing quick removal of the tank in future. If anyone can recommend a good sourse to purchase these I would be obliged. It was also mentioned that a new seal is needed for the tank itself when it is opened up to get to the fuel filter. Christ what a palaver just to get a tank off.............it's a 2 minute job on my old 400/4 !

Cheers

Scotty

ianc53 · Post by **ianc53** » Tue Oct 09, 2007 10:56 am

You can buy the fuel line couplings from BMW, although there are other sources. There are several posts in here somewhere about them. I may have the part numbers at home if you want them.

Cheers

Ian

oyster · Post by **oyster** » Tue Oct 09, 2007 5:33 pm

for fuel filter: side panels off; snorkel off; two tank bolts; lift tank from the rear then pull back. Two hoses, only pressurised when the fuel pump is on, disconnect above right inlet manifold. Mark one hose and pipe. ONLY DISCONNECT WHEN THE TANK IS EMPTY. Breather pipes for tank go down beside airbox. Electrics connector at front right of tank. Balance pipe connects two front spigots runs in a loop around the rear of the tank. Pull off one side to drain the tank. NB - petrol will run out of BOTH the spigot and the hose at the same time. Pump and filter live behind the access plate under tank on right lobe. Release cap head screws. The overflow and breather pipes connect to this plate and have to be prised off to work on the filter. DO NOT REVERSE THEM on rebuild, it stops the plate going back in. Great fun this bit. Rebuild is the reverse of the above.
I have not used any new clamps or plate seals in three removals. I did want to, but Vines sent me the wrong plate seal. It worked the first time and has worked on the two since.
If you choose the QD hose connectors, be sure to stagger them and to reverse one of them.
It's ok to smoke while doing this, just dont light the cigarette within 50 metres of the bike, tank, bucket of petrol, etc.

scotty · Post by **scotty** » Wed Oct 10, 2007 3:54 pm

Thanks again Oyster.

I ordered up all the stuff yesterday from Motoworks and it arrived today. I've got a set of couplers from BMW and I note your comments on staggering them as they are quite wide and also to reverse the male/female connectors for each pipe so they cannot be mixed up. I've got clamps to clamp the pressurized pipes so I was going to use these before cutting the pipes and removing say an inch of tubing from each tube so that the connectors can fit.

How did you clean the injectors ? I can't remember how they fit on the bike now but was it a case of simply pulling them off the inlet manifold and then cleaning with carb clean.

It was interesting to hear your comments about how your engine perked up a little after the new filter/carb clean. Mine has got a bit lethargic lately and one always suspects a slightly dirty air filter rather than anything else.

Cheers

Scott

oyster · Post by **oyster** » Wed Oct 10, 2007 4:31 pm

How did you clean the injectors ? I can't remember how they fit on the bike now but was it a case of simply pulling them off the inlet manifold and then cleaning with carb clean.

Yes. After unbolting the retaining fuel elbow.

The idea of reversing one of the connectors is so that they dont get confused; but on such short pipes, it may be difficult to get them wrong once they are staggered. Also check whether only one half of the coupling seals; if so, then that is the one to go on the tank side pipe.

scotty · Post by **scotty** » Thu Oct 11, 2007 9:05 am

Thanks Oyster

The couplers I have seal on both sides and I've noted your points re the injectors. I fitted the clean air filter last night and I'm going to wait to do the fuel filter/fuel injectors as the tank is currently nearly full with petrol. I want to empty the tank out to get rid of any water that may be in there so it'll be better tackling this when the tank is nearly empty.

Cheers

Scott