fuel filters

[scotto]

Hi guys. I know there are a wide range of views on merits of fuel filters, but I need some advice on how best to install them. My tank is evil and will be exorcised with chemicals at some point in the future, in meantime I am running with filters.

OK, I have had the carbs out 3 times already and that's enough. Have installed filters as per design on this site, but couldn't get it to run. Figured it was starving so charged bowls up directly and primed fuel line and it ran like a brand new one, till the bowls emptied. Seems like air in the lines are preventing the fuel from getting through, that or pulling the fuel against gravity through a paper fiilter is too much for it.

I will try a different routing and get filter to run with gravity next, but thought I would try the gurus for a suggestion. Surely someone has fumbled around with this issue before. Many thanks. Scott J

[mro]

I use in-line filters.
One happens to be slighly higher than the petcock feed but has no problem getting fuel to the carbs.

Check that routing the fuel lines does not result in any kinks and fuel lines should not be any longer than nesessary.
(like em just long enough to be able to place a piece of 2"X4" under tank hold down bolt with fuel lines still attached) Aids in maintenance.


mro

[TADracer]

Hi Scotto,

If you are using small inline filters the chances are that if you are starving for fuel it is not the filter. The filter body does not have to be full of gasoline to operate. Since everything is gravity feed, try to get your filters more to bowl level if you can. If you have the stock air box still on your machine, this may be a bit of a problem, though.

Like MRO, I run inline filters but my stock air box has been long gone so I have plenty of room to work in. I keep a simple setup where one line comes from each cock thru the filter and straight to each pair of carbs. A crossover is placed between the lines just before they go into the carbs to keep fuel balanced and to allow one cock to run the show, if necessary.

works for me!

[HobbyMan]

If nothing is kinked, try to blow into the tank with the petcocks on prime. Usually that will dislodge any air in the lines. If you must continually do this, I suggest a different setup. You don't want to have to blow into the tank every time you switch to reserve. What filters are you using?

[red bandit]

Sometimes if the fuel runs downhill thru the filter an air lock will occur. Turn filter so gas runs uphill thru filter???

[SFerinTEXAS]

filters

I've been using the square filters from MIKES XS. they fit real good just bearly above the intake boots, but they get solft after a few months with this gas we're getting now and should be changed ever 6 months or so. My opinion on air lock is if your fuel level is above the fuel lines you can't get an air lock unless you have a kink or blockage. MIKES ships free over $35.00 and the filters are only 2 bucks. Also has the OE thin wall fuel line. Its easier to route but tends to split if not carefull with pliers tugging it off the petcocks so i used auto fuel line from the tank to the vacumn octopus valve. I don't use the prime line off the tank because my petcocks leak a little but do have the hoses routed on the carbs. Those I hooked together in case of a need. Put caps on the tank prime nipples.

[motoman]

SF...............run the little conical filters, with lines long enough to go letf side to right petcock, right side to left petcock............then will also have enough line length to flip tank backwards set where seat would go to do carb sync.

[SFerinTEXAS]

You mean like lawn mower one's with the stone element? I have one of those on my xj550 but hav'nt been able to find them anymore. I tried the plastic one's with the paper element but they wer'nt made very well and leaked after a while. Got them at autozone in blister pack made by some german company I think. I can raise the tank ok as is.

[skids]

The Fram metal, in-line filters work well. The small cones sometimes do not keep up at highway speeds.

[motoman]

Guess it could happen.........been running these for a couple years with no problem, even at a steady 80mph for couple hundred miles. Also Sid, another set of 4into 2 Jardines you know where.

[scotto]

fuel filters

Thanks for advice guys. I am flat out at work last few days but will get back into bike tomorrow. I reckon I must have had a kink once tank was dropped into place. Wil try longer line, better routing first. If that fails, will move to conical stone filters and see how they go. Kreeming this tank is moving up the list of jobs. Cheers. Scott J

[rockjok]

I'm still looking for the ultimate filter setup but the best I've found so far are the conical inline filters. What I'm hoping to find soon is a dual inlet/dual outlet gravity filter that is transparent.

I discovered last summer from a guy at a "lawn mower" shop that some filters are designed to be under pressure rather than just gravity fed.

Rob

[oseaghdha]

Best ones I found were at the 'zone.
They are about 1.25 diameter X maybe 1.5 long and are translucent white, so you can see the crud. They have more filtering area than the bronze or little square filters, but still fit nicely under the runners between the filter box and carbs. I like the bigger diameter because air lock is not a problem.

I was working thru some tank issues, and eventually will probably eliminate the filters all together and reinstall the octopus. If your tank is in good repair and the petcock screens are good, filters are not needed. Unfortunately, this may not be the case with an almost 30 year old bike, so YMMV.

[cruiser]

Not hearing this mentioned and knowing you have a problem tank. Suggest you verify that you have full strong fuel flow from the petcocks without hoses attached. Petcock screens could be partially plugged with gunk from tank or partial blockage in petcocks themselves.

[HobbyMan]

do this by opening the fuel bowl drains and setting petcocks to prime. Check for fuel drainage flow